Abstract
As global demand for poultry products, environmental sustainability, and health consciousness rises with time, the poultry industry faces both substantial challenges and new opportunities. Therefore, this review paper provides a comprehensive overview of sustainable poultry farming, focusing on integrating genetic improvements, alternative feed, precision technologies, waste management, and biotechnological innovations. Together, these strategies aim to minimize ecological footprints, uphold ethical standards, improve economic feasibility, and enhance industry resilience. In addition, this review paper explores various sustainable strategies, including eco-conscious organic farming practices and innovative feed sources like insect-based proteins, single-cell proteins, algal supplements, and food waste utilization. It also addresses barriers to adoption, such as technical challenges, financial constraints, knowledge gaps, and policy frameworks, which are crucial for advancing the poultry industry. This paper examined organic poultry farming in detail, noting several benefits like reduced pesticide use and improved animal welfare. Additionally, it discusses optimizing feed efficiency, an alternate energy source (solar photovoltaic/thermal), effective waste management, and the importance of poultry welfare. Transformative strategies, such as holistic farming systems and integrated approaches, are proposed to improve resource use and nutrient cycling and promote climate-smart agricultural practices. The review underscores the need for a structured roadmap, education, and extension services through digital platforms and participatory learning to promote sustainable poultry farming for future generations. It emphasizes the need for collaboration and knowledge exchange among stakeholders and the crucial role of researchers, policymakers, and industry professionals in shaping a future where sustainable poultry practices lead the industry, committed to ethical and resilient poultry production.
Key words: sustainability, animal welfare, climate-smart practice, environment, market opportunity
INTRODUCTION
The world's population is rapidly growing and is projected to increase by 2 billion people over the next 27 yr. It is expected to reach a remarkable 9.7 billion by 2050 (United Nations, 2019). An increase in population increases food demand and supply. The poultry industry emerges as the most important food supplier among different food suppliers. Poultry meat represented nearly 40% of global meat production in 2020 and over the last three decades (FAO, 2023a). In addition, egg production witnessed a remarkable 150% increase, with Asia playing a substantial role in driving this growth. China dominates egg production worldwide by producing 38% of the global output. The United States produces 17% of the global poultry production output and is the world's largest poultry meat producer (FAO, 2023a). This expansion of the poultry sector is driven by factors such as an increasing population, economic capacity, and the trend toward urban living. Thus, the poultry industry is pivotal in addressing global protein demands amidst evolving demographics and lifestyles (Mottet and Tempio, 2017; FAO, 2023a). However, this remarkable potential of the poultry industry comes with substantial challenges, especially regarding sustainability (Castellini et al., 2006; Vaarst et al., 2015; Leinonen and Kyriazakis, 2016; Cui et al., 2021).
In addition to poultry supply, it is crucial to address environmental preservation. Adapted poultry farming must evolve to secure long-term viability for sustainability (Bist et al., 2024b; Guo et al., 2024; Kheiralipour et al., 2024). Sustainable poultry farming practices have become imperative, not only for preserving natural resources and mitigating environmental impacts but also for ensuring the welfare of the birds and the livelihoods of the poultry farmers who depend on this poultry industry (Jez et al., 2011; Vaarst et al., 2015; Castro et al., 2023). The challenges confronting the poultry industry regarding sustainability are multifaceted (Vaarst et al., 2015; Leinonen and Kyriazakis, 2016). Intensive conventional farming practices have resulted in excessive resource consumption, water pollution, ammonia emissions, antibiotic resistance, and ethical concerns (Grzinic et al., 2023). These poultry farming practices have grown rapidly but have raised concerns about environmental sustainability (Bist et al., 2023b; FAO, 2023b). The use of antibiotics as growth promoters has given rise to concerns related to antimicrobial resistance, which threatens the health of humans and animals (Castanon, 2007; Ma et al., 2021). Additionally, ethical concerns about animal welfare in crowded and confined systems have spurred a call for more humane practices.
The adoption of sustainable practices in poultry farming holds paramount importance in ensuring the industry's resilience and long-term success. These sustainable methods optimize resource use, reduce environmental impacts, and support biodiversity conservation (Figure 1) (Sullivan, 2003; Castellini et al., 2006; Vaarst et al., 2015). Poultry farmers can minimize their carbon footprint by adopting eco-friendly techniques, contributing significantly to climate change (Mottet and Tempio, 2017). In 2010, improvements in background systems and bird performance were the main drivers behind a significant reduction in environmental impacts and resource requirements in U.S. poultry meat production compared to 1965 (Putman et al., 2017; National Chicken Council. 2019. National chicken council unveils new sustainability resources, 2019). Additionally, resource-related impacts showed significant reductions, including water depletion (58%), fossil energy use (39%), and agricultural land utilization (72%) per 1,000 kg of poultry meat produced. A paradigm shift towards sustainable poultry farming practices is imperative to address these challenges. These practices boost poultry welfare, leading to healthier birds and better product quality (Vaarst et al., 2015). In addition, consumer preferences are evolving for ethically produced and environmentally conscious poultry products (Carter, 2007). Embracing sustainability aligns with these changing consumer preferences, opens new market opportunities, and enhances the industry's competitiveness.
Figure 1.
Framework of sustainable poultry production.
The primary objectives of this review paper are to: (1) explore and analyze the current strategies employed in sustainable poultry farming and identify prospects for further improvement, (2) delve into various critical aspects of sustainable poultry farming, including organic poultry farming, alternative feed sources, waste management, animal welfare, community engagement, technology, and the impact of genetics and biotechnology, (3) compare economic variability & market opportunities, and (4) discuss challenges, barriers, future direction and recommendation for implementing sustainability poultry farming practices. This review provides valuable insights and recent research to guide poultry farmers, researchers, policymakers, and industry stakeholders toward sustainable and prosperous practices.
SUSTAINABLE POULTRY FARMING CONCEPT
"Sustainability" and "sustainable development" are intricate and debated concepts due to their connections with various sectors and the global food system (Vaarst et al., 2015). The 1987 Brundtland Report introduced the concept of sustainable development as "Our Common Future" (Brundtland, 1987). Sustainable development is the type of development that fulfills present-day needs without compromising the ability of future generations to meet their own needs. The Brundtland report brought sustainability to the forefront of policy discussions and popularized the idea of sustainable development. Similarly, the Food and Agricultural Organization (FAO) defines sustainable agricultural development as managing natural resources, technology, and institutions to meet present and future human needs while conserving land and water (FAO Council, 1989). It should also be technically suitable, economically viable, socially acceptable, and eco-friendly. Sustainability in poultry farming embodies a holistic approach that encompasses environmental stewardship, economic viability, and social responsibility (Figure 2) (Brundtland, 1987; FAO Council, 1989; Vaarst et al., 2015). At its core, it seeks to balance these 3 interconnected dimensions harmoniously. Environmental sustainability involves practices that reduce the ecological footprint of poultry production, including minimizing resource consumption, managing waste and emissions, and safeguarding natural ecosystems. Simultaneously, economic viability is pivotal, ensuring that poultry farming remains profitable for producers, encouraging long-term adoption through cost-efficient resource utilization, market competitiveness, and resilience to economic fluctuations. Furthermore, social equity is integral, emphasizing fair labor practices, animal welfare, and community engagement. Sustainable poultry farming strives to maintain the well-being of farmworkers, ensure the ethical treatment of animals, and foster positive relationships with surrounding communities. However, Valentin and Spangenberg (2000) proposed a fourth crucial aspect of sustainability: "Institutional sustainability." Institutional sustainability involves managing and governing global systems while emphasizing the need for accountable, transparent, and open institutions that engage with their members and representatives (United Nations, 1992).
Figure 2.
Four most important pillars of sustainability farming.
The concept of sustainable poultry farming recognizes the interdependence of these dimensions and acknowledges that addressing one aspect should not come at the expense of the others. Achieving sustainability involves trade-offs and challenges that improve one dimension and may impact another. Navigating these complexities is vital to ensure a future where poultry farming maintains its role in global food security while reducing its negative effects on the environment and society. In a world facing challenges like climate change, resource scarcity, and shifting consumer preferences, the pursuit of sustainable poultry farming practices gains even more importance. It signifies responsible environmental stewardship and a dedication to economic viability and social responsibility in a continually evolving agricultural context (Jez et al., 2011).
POULTRY HOUSING SYSTEMS TOWARD SUSTAINABILITY
Poultry production facilities are the main part to target to improve sustainability because they face many challenges, such as pollution, depletion of natural resources, animal welfare concerns, and human health risks (Leinonen and Kyriazakis, 2016; Mottet and Tempio, 2017). Various poultry housing systems have been developed to address these pressing issues. However, each housing type has its advantages and disadvantages. These systems include conventional cages, enriched cages, free-range, pasture-raised systems, multi-tiered aviaries, mobile poultry units (commonly called chicken tractors), agroforestry integration, and organic systems. Conventional cages offer efficient space utilization and reduced disease transmission but compromise animal welfare due to confined spaces (McMullin, 2022). Free-range and pasture-raised systems prioritize high animal welfare and natural behaviors but have a higher environmental impact, increased disease risk, and greater land requirements. Multi-tiered aviaries offer a space-efficient solution, improved bird movement, and effective waste management, but they require initial investments (Matthews and Sumner, 2015). Mobile poultry units foster sustainable practices by providing fresh forage for birds and promoting soil regeneration while enabling direct-to-consumer marketing. Agroforestry integration combines poultry farming with tree cultivation, enhancing biodiversity and carbon sequestration, but requires more space and management (Brown et al., 2018). Organic systems prioritize biodiversity, animal welfare, and reduced synthetic input (Guarino Amato and Castellini, 2022). The significance of organic poultry farming is increasing compared to other poultry farming methods, and this review paper provides a detailed examination of organic poultry farming.
Organic Poultry Farming
Organic poultry farming embodies ecological production practices prioritizing biodiversity, animal welfare, environmental sustainability, food safety, and quality (European Union, 1999). It represents a significant shift towards sustainability, emphasizing natural processes and environmental responsibility. The core principles of organic poultry farming revolve around minimizing synthetic inputs, promoting animal welfare, and nurturing ecosystem health. While organic farming aligns with local sustainability goals, its global impact is challenging to assess accurately (European Union, 1999). To evaluate sustainability effectively, we need comprehensive measurements that consider short- and long-term suitability and enable comparisons between different systems. With their reduced reliance on fossil fuels and emphasis on integration, organic livestock systems have a unique potential to influence supply-demand dynamics. However, their environmental impacts, price competitiveness, interactions with conventional production methods, and broader factors like food availability and climate change require further exploration. Understanding these dynamics is crucial for shaping the future of sustainable poultry farming.
Principles and Certification. Organic poultry farming adheres to a set of core principles to ensure the well-being of birds, environmental sustainability, and consumer confidence (European Union, 1999). These principles include providing outdoor access to birds, enabling natural behaviors, and using organic, non-GMO feed while avoiding growth-promoting antibiotics. Recycling nutrients through composting and waste utilization further contributes to sustainability (Sinha and Tripathi, 2021). The certification process is pivotal in maintaining organic integrity, with governmental and private bodies conducting inspections and audits to verify compliance with stringent organic standards (2014). Certification ensures that organic poultry products bear the trusted organic label, enhancing marketability and bolstering consumer trust in the organic farming system.
From 2002, poultry products could carry the organic label if they met U.S. National Organic Standards Board requirements (USDA, 2013). However, using organic as a product name was prohibited due to species declaration regulations. The USDA Food Safety and Inspection Service (FSIS) accepted organic certificates from accredited certifying entities and followed a procedure similar to certifying entities for label approval. From April 21, 2002, to October 21, 2002, FSIS evaluated labels with the organic claim. Still, they could not use the USDA organic seal until the Agricultural Marketing Service (AMS) final rule fully took effect on October 21, 2002 (USDA, 2013). Companies using the Certified Organic by Certifying Entity claim were expected to comply with National standards by that date.
Environmental Benefits. Compared with conventional agriculture, organic farming uses fewer pesticides, reduces soil erosion, decreases nitrate leaching into groundwater and surface water, and recycles animal waste into the farm (Agricial, 2023). However, certain negative environmental aspects of organic farming are linked to decreased efficiency when slower-growing breeds are used for meat production and when birds are allowed to range outdoors (Edwards, 2019). Notably, organic farming significantly curbs erosion (Mullen, 2021), with recent research revealing that organic farms boast eight inches more topsoil than chemically treated farms (Leinonen and Kyriazakis, 2016). Furthermore, organic poultry systems display improved animal welfare, manifesting as enhanced leg health in broilers (attributed to slower-growing breeds) and increased stress resistance (Tuyttens et al., 2008). However, organic systems may exhibit poorer animal welfare due to a higher incidence of worm infections (Thapa et al., 2015).
Poultry farming has relatively modest impacts on land requirements, water usage, environmental stress, and carbon footprints (De Vries and de Boer, 2010). Nevertheless, it is crucial to acknowledge the potential environmental burdens associated with transportation despite its current affordability. Overall, organic poultry farming delivers numerous environmental benefits by significantly reducing synthetic chemicals safeguarding soil, water, and surrounding ecosystems. It also encourages carbon sequestration through agroforestry and the preservation of natural vegetation (Jez et al., 2011). Integrating trees within the poultry farming system provides shade and acts as a carbon sink, contributing to the mitigation of greenhouse gas emissions and the fight against climate change.
Consumer Perception and Market Demand. Sustainable poultry farming is a dynamic field presenting various challenges and opportunities. With the global demand for poultry products projected to double by 2050, the urgency to develop resource-efficient and eco-friendly poultry systems becomes increasingly apparent (Vaarst et al., 2015). However, consumer perspectives on poultry products are diverse and influenced by quality, safety, pricing, animal welfare, and environmental impact (McCarthy et al., 2004; Henchion et al., 2014). Most importantly, the consumer perspective is influenced by cultural, educational, income, awareness variables, and the transparency of poultry products. Meeting these varying consumer expectations through the disclosure of production practices and product attributes is essential.
Consumer perception of organic poultry products is increasingly positive due to their health benefits and ethical considerations (Harper and Makatouni, 2002; Van Loo et al., 2010). Organic poultry is believed to have lower synthetic residues, hormones, and antibiotics, making it a healthier option for consumers (Van Loo et al., 2010). Organic poultry also contains essential nutrients such as vitamins and omega-3 fatty acids (Alagawany et al., 2019). Moreover, the assurance of better animal welfare practices in organic systems resonates with consumers who prioritize the ethical treatment of animals. The demand for organic poultry products has steadily grown in recent years (Van Loo et al., 2010). Consumers seeking sustainable and environmentally friendly food choices are willing to pay a premium for organic poultry products (Martinez Michel et al., 2011). As a result, many poultry farmers have transitioned to organic production to capitalize on this growing market demand and achieve a price premium for their products. Moreover, heightened consumer awareness regarding the health advantages of organic food has significantly contributed to the positive trajectory of the organic poultry market (Van Loo et al., 2010; Schipmann-Schwarze and Hamm, 2020).
The COVID-19 pandemic has disrupted consumption patterns, transportation logistics, and the economic landscape of poultry farming (Hafez, 2020). Market segmentation is crucial for understanding consumer perceptions and demands, particularly concerning animal welfare in food products (Verbeke, 2009). Limited examples in the literature focus on segmenting the market based on pro-welfare behavior. According to the NCC survey, the environmental impact of chicken (34%) is now just as significant as animal welfare (37%) in influencing purchase decisions (National Chicken Council, 2019. ). Nearly half (49%) of the survey participants were willing to consume more chicken if they were informed that it is more sustainable than other protein sources. A survey of West Coast consumers commissioned by Foster Farms revealed that nearly half of respondents expressed heightened concerns about animal welfare and the treatment raised for food compared to 5 yr ago (Animal Welfare Institute, 2019). Additionally, a substantial majority (74%) agreed they preferred large producers to raise animals for food humanely. A British report commissioned by Freedom Food identified 4 shopper profiles based on the frequency of purchasing higher welfare products: high welfare (10%), some welfare (34%), little welfare (20%), and no welfare (36%) (Carter, 2007). Similarly, in a Flemish study, consumers were categorized based on their purchase frequency of higher welfare eggs and chicken meat into 5 categories: all (26.6% and 14%), regular (21.3% and 17.6%), little (12.4% and 17.3%), some (14.4% and 19.1%), and no (higher welfare; 25.3% and 32.1%) (Vanhonacker and Verbeke, 2009). This segmentation approach is vital for understanding and catering to diverse consumer preferences in the market.
Opportunities, Challenges, and Limitations. Opportunities in poultry farming encompass its remarkable versatility, adaptability to diverse farming systems, and multifaceted contributions to agriculture and sustainability. Poultry integrates into various contexts (from urban to rural and agroforestry systems), offering farmers benefits such as pest control, soil enrichment, and economic well-being (Vaarst et al., 2015; Hafez, 2020). Despite its numerous merits, organic poultry farming presents unique challenges and limitations related to market volatility, emerging diseases, antibiotic resistance, and policy dynamics (Hafez, 2020; AgMRC, 2021). One significant hurdle is the higher production costs associated with organic practices (AgMRC, 2021). Organic feed (mainly sourced from non-GMO and organic ingredients) inevitably comes at a premium price compared to conventional feed. Additionally, strict requirements for organic certification can substantially inflate operational expenses regarding infrastructure development and land management. Another formidable challenge is scaling organic poultry production to meet growing market demand. Transitioning from conventional to organic farming practices demands meticulous planning and often requires reducing flock size during the transitional period. This process leads to short-term economic challenges and affects the farmers, who are constrained by financial limitations.
Besides the economic aspect, disease management is another distinct challenge faced due to antibiotic use restrictions in the poultry industry (Haque et al., 2020). Organic farmers depend heavily on preventive measures like proper housing and nutrition to reduce the risk of disease outbreaks. However, this method requires more expertise and precise management techniques to adequately uphold the well-being of organic poultry populations. It is crucial to prioritize maintaining the authenticity of organic certification across the entire supply chain. The risk of fraudulent activities or mislabeling can reduce consumer trust and harm the reputation of the organic poultry sector (Bandoim, 2020; Lianou et al., 2021). Addressing these challenges requires collaboration among policymakers, researchers, and industry stakeholders to support poultry farmers and enhance the accessibility and affordability of organic products in the market (Hafez, 2020). This collective effort will be pivotal in securing a sustainable and ethical future for poultry farming.
ALTERNATIVE POULTRY FEED SOURCES
Poultry farming is generally considered more environmentally friendly than other livestock production but still contributes to environmental issues like global warming, eutrophication, and acidification (Leinonen and Kyriazakis, 2016). These challenges are particularly linked to feed production, transportation, and manure management. There has been a growing interest in sustainable and innovative alternative feed sources in poultry farming to address these concerns (El-Deek et al., 2020; Belhadj Slimen et al., 2023). These alternatives offer several benefits, including reduced dependence on traditional ingredients like soy and fishmeal, lower environmental impact, and potential cost savings (Figure 3). Feed production and transportation are major contributors to global warming (accounting for 70% of the issue), while manure management is responsible for 40 to 60% of eutrophication and acidification (Leinonen and Kyriazakis, 2016). Improving feed efficiency through genetic selection or enhanced digestibility using enzymes is crucial to mitigating these impacts. However, changes in bird requirements regarding protein sources may limit the benefits of genetic selection. Alternative feed ingredients like locally grown protein crops and agricultural by-products show promising results with no negative effect on bird performance (Vaarst et al., 2015). Additionally, innovations in poultry housing and manure management strategies offer potential pathways to enhance the environmental sustainability of the poultry industry (Leinonen and Kyriazakis, 2016).
Figure 3.
Various alternative feed sources in the poultry industry.
Insect-Based Protein
Insect-based protein has emerged as a promising solution for enhancing poultry nutrition while addressing environmental concerns and reducing production costs (van Broekhoven et al., 2015; Sogari et al., 2019; Belhadj Slimen et al., 2023; Sajid et al., 2023). The insects like black soldier fly larvae and mealworms, are rich in protein (35–53%), essential amino acids, and minerals, with a high digestibility rate (Waithaka et al., 2022; Sajid et al., 2023). Insect-based protein offers several advantages over traditional sources like soybean and fish meal (Oonincx and De Boer, 2012; Sogari et al., 2019; Belhadj Slimen et al., 2023). These advantages are significantly lower greenhouse gas emissions and water footprints, reducing environmental impact (Oonincx and De Boer, 2012). In addition, insect farming is resource-efficient, demanding minimal water and land resources compared to conventional feed production, leading to a significantly reduced ecological footprint. They can efficiently be reared on organic waste, aligning with circular economy principles (Sogari et al., 2019; Belhadj Slimen et al., 2023). Adding insects into poultry diets aligns with birds' natural insect-eating behavior, resulting in benefits such as faster growth, better feed conversion efficiency (Belhadj Slimen et al., 2023; Sajid et al., 2023), superior meat quality, and the supply of essential nutrients such as methionine (Sogari et al., 2019). However, these alternatives face persistent challenges like technological innovation for large-scale production, cost-effectiveness, harmonizing regulatory frameworks, and addressing consumer acceptance influenced by cultural and psychological factors (Oonincx and De Boer, 2012; Sogari et al., 2019; Belhadj Slimen et al., 2023). Overcoming these challenges is essential to fully leverage insect-based protein's potential in poultry nutrition.
Researchers have thus far identified and confirmed 13 insect species suitable for poultry feed. Among these, eight insects have been approved for use as both food and feed by EU regulations (Figure 4) (Belhadj Slimen et al., 2023). Extensive research has primarily focused on the black soldier fly. However, other insects (houseflies, mealworms, beetles, locusts, silkworms, and cockroaches) have also gained attention as potential insect-based protein sources for poultry nutrition. Regulatory frameworks governing insect production for poultry feed vary significantly across different countries and regions (Sogari et al., 2019; Belhadj Slimen et al., 2023). In addition, consumer acceptance and perceptions of insect-based products can be influenced by cultural and psychological factors (Sogari et al., 2019). Therefore, addressing these regulatory and consumer-related challenges is essential to fully unlock the potential of insect-based protein. Research and development efforts are needed to ensure insect-based protein safety, quality, and sustainability in poultry farming (Sogari et al., 2019; Belhadj Slimen et al., 2023).
Figure 4.
Eight insects approved for poultry feeding. Figures are generated and edited from https://www.biorender.com/.
Table 1 summarizes the nutritional composition of various insects and common alternative protein sources in terms of percentage content. Insects like houseflies, beetles, locusts, and crickets exhibit varying protein and fat content. Houseflies contain 45.84% protein and 19.3% fat, making them promising protein sources for poultry feed and sustainable food production. Birds tend to favor foods that are closer to their protein needs. As broilers mature, they shift towards lower protein diets, aligning with their changing protein-to-energy requirements. High-growth strains with the potential for more lean meat prefer higher protein foods (Forbes and Shariatmadari, 1994). However, birds bred for fat deposition prefer lower protein-to-energy ratios than lean birds. Earthworms and silkworms stand out with high protein levels (63.0% and 75.6%) and low fat and fiber content. Black soldier fly larvae are recognized for their high protein content (59.0%). Comparatively, traditional protein sources like fishmeal (65.0% protein) and soybean meal (48.0% protein) offer varying protein and fat levels. Insects offer a compelling alternative to conventional protein sources, potentially reducing environmental impact and enhancing food security.
Table 1.
Nutritional composition of insect-based protein for poultry sustainability.
| Insect types | Dry matter (%) | Crude protein (%) | Crude fat (%) | Crude ash (%) | Crude fibre (%) | References |
|---|---|---|---|---|---|---|
| Housefly1 | 74.16 | 45.84 | 19.3 | 4.43 | 6.14 | Ukanwoko and Olalekan, 2015 |
| Beetle2 | - | 67.85 | 20.68 | 5.01 | 7.29 | Despins and Axtell, 1995 |
| Locust | 97.175 | 36-40 | 41-43 | 2.6-3.9 | 11-14.5 | Ojewola et al., 2005; Ssepuuya et al., 2017 |
| Cricket | - | 63.3 | 17.3 | 5.6 | 18.3 | Makkar et al., 2014 |
| Earthworm | 91.4 | 63.0 | 5.9 | 8.9 | 1.9 | Moreki and Tiroesele, 2012 |
| Black Soldier fly3 | 95.9 | 59.0 | 11.0 | 5.0 | - | Maurer et al., 2016 |
| Mealworm4 | 96.46 | 63.34 | 7.59 | 3.56 | 19.96 | Ravzanaadii et al., 2012 |
| Silkworm6 | - | 75.6 | 4.7 | 6.8 | 6.6 | Sheikh et al., 2018 |
| Maggot | 90.0 | 51.25 | 3.48 | 17.30 | 9.20 | Adewolu et al., 2010 |
| Fishmeal | 94.7 | 65.0 | 3.65 | 12.56 | 1.03 | |
| Soybean meal | 90.0 | 48.0 | 6.8 | 6.5 | 7.0 | |
| Maize | 90.1 | 9.5 | 4.0 | 3.9 | 1.4 | |
| Feather meal | 95.24 | 73.76 | 10.30 | 2.43 | 10.60 |
Housefly larva meal with egg attractant.
darkling bettle larvae.
Dried, partly defatted (g/100g fresh matter).
Adult mealworm.
Defatted pupae meal.
Previous research studies on alternative insect-based feeds highlight several key findings (Table 2). Firstly, insect-based diets in poultry feed can affect performance parameters. These include feed intake improvements, weight gain, and certain meat characteristics. However, several challenges may arise based on the type and amount of insect inclusion, such as altered feed conversion ratios or impacts on gut morphology. There were observations related to egg quality for laying hens, with some studies indicating reductions in eggshell thickness and foaming capacity when using insect-based diets. Despite these variations, many studies did not find significant adverse effects on overall performance. Some insect-based diets were associated with positive impacts, including improved yolk color and lower egg cholesterol levels. These findings suggest that insect-based feeds can potentially be valuable, sustainable, and nutrient-rich protein sources, but further research and optimization are needed for specific uses and species.
Table 2.
Performance and impact of insect-based protein feed on poultry production sustainability.
| Poultry type | Insect-based diet | Target diet replacement | Insect-based diet (%) | Results | References |
|---|---|---|---|---|---|
| Broiler | Black soldier fly larva | Fish meal | 0,2,4,6,8 | Feed intake and FCR decreased at 4 and 6% treatment. Higher body weight gain at 8% treatment but no difference at the end of treatment. |
Attivi et al., 2020 |
| Broiler | Partially defatted BSF larva | Soybean meal, soybean oil, corn gluten meal | 0,5,10,15 | 15% treatment of houseflies in a diet may reduce microbial diversity, beneficial bacteria, and mucin in villi. | Biasato et al., 2020 |
| Broiler | Partially defatted BSF larva | Soybean meal, soybean oil, corn gluten meal | 0,5,10,15 | Increasing black soldier fly meal in the diet can enhance live weight and feed intake during the starter period but negatively affect FCR and gut morphology while having no significant impact on blood parameters or tissue structure. | Dabbou et al., 2018 |
| Broiler | Defatted BSF larva | Soybean meal, soybean oil, corn gluten meal | Basal diet (Corn+Soybean meal), Substituted 250g/kg of basal diet with Defatted BSF larva | Defatted BSF larvae are rich in apparent metabolizable energy and digestible amino acids, aiding efficient nutrient digestion in broilers and enhancing poultry feed. | Schiavone et al., 2017 |
| Broiler | Housefly larva | Soybean meal | 0, 5 (1-7 d), 4 (8-42 d) | Higher feed-gain ratio and body weight. Increase feed consumption and feed conversion. Meat tastes favorable in terms of flavor, aroma, and desirability. |
Radulovic et al., 2018 |
| Broiler | Housefly larva, Silkworm, mealworm | Soybean meal | 0, 8 | Mealworm diets led to reduced overall feed consumption and increased weight gain. The mealworm diet had the lowest FCR. Tenderness and juiciness of meat were higher in meat fed with mealworms. |
Khan et al., 2018 |
| Broiler | Earthworm | Soybean meal | 0, 7.7, 15.4 | Higher breast muscle weight and crude protein digestibility fed with earthworm. | Rezaeipour et al., 2014 |
| Laying hen | Live BSF larva | Soybean meal | 0,10 | Better feather condition feed with BSF. No significant difference in FCR, BW gain, and egg-laying parameters. |
Star et al., 2020 |
| Laying hen | Partially defatted BSF larva | Soybean meal | 0, 25, 50% of dietary proteins | Significant reductions in eggshell percentage and thickness with 50% treatment. Egg albumen exhibited reduced (almost half) foaming capacity with 50% treatment. |
Secci et al., 2020 |
| Laying hen | Defatted BSF larva | Soybean meal | 0, 17.4 | Hen feed with BSF has a higher proportion of yolk with redder yolks and is rich in γ-tocopherol, lutein, β-carotene, and total carotenoids. Yolk with 11% less cholesterols fed with BSF. |
Secci et al., 2018 |
| Laying hen | Locust (Grasshopper) | Fishmeal | 0, 25, 50, 75, 1001 | No Significant difference in laying rate, egg weight, albumin height, eggshell thickness, daily feed intake, and feed efficiency. Grasshopper meal improved yolk color and Haugh Unit. |
Brah et al., 2017 |
| Laying hen | Housefly larva | Fishmeal | 0, 0.9, 1.8, 2.7, 3.6 | No significant difference in daily feed intake, feed efficiency, egg weight, hen-day production, and livability. Housefly meal significantly decreased egg yolk cholesterol and calcium levels. |
Akpodiete et al., 1998 |
| Turkey | Live BSF larva | Soybean meal | 0, 12 | When fed with BSF, there is a significantly higher daily feed intake, BW gain, and lower FCR. Aggressive pecking was lowered in BSF-fed turkey diet. |
Veldkamp and Van Niekerk, 2019 |
| Japanese laying Quail | BSF larva | Fishmeal | 0, 3.18, 6.37, 9.56 | BSF meal increased secondary humoral immune response. BSF meal had immunostimulatory effects. No significant effect on caecal bacterial counts. |
Pasotto et al., 2020 |
Percentages of fish meal in the control diet replaced with grasshopper meal.
Single-Cell Protein
Single-cell protein (SCP) is derived from various microorganisms such as yeast, bacteria, and fungi (Matelbs and Tannenbaum, 1968; Goldberg and Single, 2013; Suman et al., 2015; Sharif et al., 2021). Single-cell protein represents a valuable and cost-effective feed additive that provides a rich source of high-quality protein, amino acids, vitamins, and minerals (Suman et al., 2015; Bratosin et al., 2021). It offers sustainable protein production with protein content ranging from 12% to 76.4% (Table 3). Additionally, it lowers the environmental impact typically associated with traditional feed ingredients (Bratosin et al., 2021; Bhandari et al., 2022). Several research papers discuss the use of SCP in sustainable poultry farming. For instance, Zampiga et al. (2021) explored the significance of feed efficiency in sustainable chicken meat production and the role of feed additives as alternative protein sources. Bratosin et al., 2021 provided a comprehensive overview of SCP production and utilization, encompassing substrates, microorganisms, nutritional benefits, and economic considerations. It highlights the advantages of SCP in human and animal nutrition. Additionally, researchers assessed the impact of SCP derived from yeast on broiler chicken growth performance, noting improvements in body weight gain and feed conversion ratio at 5% and 10% inclusion levels (Al-Shadeedl and Muhklis, 1988) while cautioning against the use of 15% SCP in poultry diets (Najib et al., 2014). Furthermore, the inclusion of 5% yeast in the ration significantly improved the performance of the hen's egg mass, hen-day egg production, feed conversion, and egg weight.
Table 3.
Microbial and fungal single-celled protein sources and their protein content.
| SCP type | Type | Medium | Protein content (%) | Reference |
|---|---|---|---|---|
| Bacteria | Rhizospheric diazotrophs | Brewery wastewater | >55 | Lee et al., 2015 |
| Bacteria | Haloarcula sp. IRU1 | Petrochemical wastewater | 76.4 | Taran and Asadi, 2014 |
| Bacteria | Rhodopseudomonas palustris | Latex rubber sheet wastewater | 65 | Kornochalert et al., 2014 |
| Bacteria | Bacillus subtilis | Soya bean hull | 12 | Wongputtisin et al., 2014 |
| Bacteria | Bacillus licheniformis | Potato starch processing waste | 38.2 | Liu et al., 2014 |
| Bacteria | Bacillus subtilis | Ram horns | 71 | Kurbanoglu and Algur, 2002 |
| Bacteria | Bacillus cereus | Ram horns | 68 | |
| Bacteria | Rhodopseudomonas palustris | Volatile fatty acid | 67 | Alloul et al., 2021b |
| Rhodobacter capsulatus | 66.9 - 73.7 | |||
| Bacteria | Rhodobacter capsulatus | Volatile fatty acid | 54 | Alloul et al., 2021a |
| Bacteria | R. faecalis PA2 | Chicken manure | 62.7 | Patthawaro and Saejung, 2019 |
| Bacteria | R. faecalis | Sugar industry wastewaters | 51.5 | Saejung and Salasook, 2018 |
| Bacteria | Rhodopseudomonas sp. and Rhodobacter sp. | Domestic wastewater | 57.7 | Delamare-Deboutteville et al., 2019 |
| Bacteria | Rhodopseudomonas faecalis PA2 | Domestic wastewater | 64.8 | Saejung and Ampornpat, 2019 |
| Fungi | Kluyveromyces marxianus | Orange pulp, molasses, brewers spent grain, whey, potato pulp | 33.7 | Aggelopoulos et al., 2014 |
| Fungi | Aspergillus niger | Waste liquor | >50 | Chiou et al., 2001 |
| Fungi | Aspergillus niger | Stick water | 48.7 | Kam et al., 2012 |
| Yeast | S. cerevisiae | Orange pulp, molasses, brewer's spent grain, whey, potato pulp | 38.5 | Aggelopoulos et al., 2014 |
| Yeast | Candida tropicalis | Soy molasses | 56.4 | Gao et al., 2012 |
| Yeast | Candida. utilis | Waste capsicum powder medium | 48.2 | Zhao et al., 2010 |
| Candida tropicalis | 46.5 | |||
| Saccharomyces cerevisiae 1027 | 25.4 | |||
| Saccharomyces cerevisiae 1335 | 40.5 |
Single-cell protein offers a sustainable solution for poultry feed, which can thrive on diverse substrates, including agricultural and food industry by-products (Figure 5) (Suman et al., 2015; Bratosin et al., 2021). Single-cell protein production can effectively utilize waste streams, mitigating waste and environmental pollution and reducing the reliance on arable land and freshwater resources (Nasseri et al., 2011; Bhandari et al., 2022). Future research should optimize SCP production processes, enhance its nutritional profile, and assess its long-term impact on poultry health and performance, thereby holding significant potential for a more sustainable and resource-efficient poultry industry (Nasseri et al., 2011).
Figure 5.
Illustrating the sequential phases in single-celled protein production.
Algal and Seaweed Supplements
Algae and seaweeds have gained increasing attention as viable feed supplements for poultry due to their abundant, renewable nature, and environmentally friendly characteristics (Suganya et al., 2016; Ahmad and Ashraf, 2023). It requires minimal land and no freshwater. They can also contribute to carbon dioxide mitigation through photosynthesis (Suganya et al., 2016). It contains high-quality protein, essential fatty acids, vitamins, and minerals (Kulshreshtha et al., 2020). Some algae species contain unique bioactive compounds that can positively influence poultry health and enhance disease resistance. Researchers actively explore algae strains to optimize their cultivation and processing for poultry feed applications (Coudert et al., 2020; Kulshreshtha et al., 2020; Ahmad and Ashraf, 2023). However, challenges in this field include scaling up algae production, maintaining consistent nutritional profiles, and addressing potential environmental impacts associated with large-scale seaweed farming. Despite these challenges, algal and seaweed supplements represent promising alternative feed sources and offer potential environmental benefits, animal health, and product quality.
A wide variety of algae and seaweeds can serve as feed supplements for poultry, including Chlorella, Spirulina, Ulva, Ascophyllum, Laminaria, and Sargassum (Coudert et al., 2020; Kulshreshtha et al., 2020). Algae and seaweeds like Spirulina (63.0% protein) and Chlorella (47.8% protein) are nutrient-rich options for poultry feed (Table 4). They offer sustainability benefits due to efficient cultivation and low environmental impact. These ingredients can enhance poultry health and reduce the strain on terrestrial resources. The utilization of seaweeds in poultry diets has been the subject of extensive research over the past few decades, particularly regarding their role as sources of complex carbohydrates with prebiotic activities, pigments, and polyunsaturated fatty acids that benefit animal health (Evans and Critchley, 2014). In addition, various brown, green, and red seaweed species are already commercially sold in the Canadian and U.S. poultry markets. The chemical makeup of different seaweeds varies significantly (depending on species) in habitat, light intensity, temperature, collection time, and nutrient levels. Brown seaweeds are rich in minerals (14%–35% dry matter) and can accumulate iodine at levels over 30,000 times higher than in seawater (1,500–8,000 ppm vs. 0.05 ppm) (Misurcova, 2011). Red seaweed may have protein content ranging from 10% to 50% dry matter and lower iodine levels (Misurcova, 2011; Peng et al., 2015). Green seaweed (Sea Lettuce) can contain higher protein amounts, reaching up to 15%, compared to brown seaweed. Green algae are also fiber-rich, including soluble and insoluble fibers (Overland et al., 2019).
Table 4.
Nutrient composition of algal and seaweed species.
| Nutrient Value (%) | Spirulina platensis | Chlorella vulgaris | Isochrisis galbana | Gracilaria edulis | Sargassum Sp. | Ulva lactuca | Ascophyllum nodosum |
|---|---|---|---|---|---|---|---|
| Moisture | 3.7 | 3.9 | 6.5 | 87.1 | 81.8 | 84.8 | 12.0 |
| Crude Protein | 63.0 | 47.8 | 27.0 | 14.3 | 18.2 | 13.8 | 6.0 |
| Crude Lipid | 7.4 | 13.3 | 17.2 | 0.9 | 0.73 | 0.86 | - |
| Total ash | 8.4 | 6.3 | 16.1 | 7.6 | 13.0 | 12.4 | 22.0 |
| Carbohydrates | 15.4 | 8.1 | 17.0 | 32.4 | 30.3 | 43.2 | 52.0 |
| Fiber | - | - | - | 63.2 | 58.3 | 53.6 | 6.0 |
| Minerals (mg/kg) | |||||||
| Sodium | 126.3 | 134.6 | 110.9 | 423.3 | 389.3 | 351.7 | 2.4 - 4.01 |
| Potassium | 141.3 | 5.0 | 119.3 | 282.5 | 244.3 | 209.0 | 2 – 31 |
| Calcium | 82.6 | 59.4 | 108.1 | 223.3 | 176.0 | 180.7 | 1 – 31 |
| Magnesium | 38.9 | 34.4 | 68.9 | - | - | - | 0.5 – 1.01 |
| Iron | 9.5 | 25.9 | 22.8 | 65.3 | 32.2 | 34.5 | - |
| Zinc | 0.3 | 0.1 | 0.3 | 1.7 | 5.8 | 1.8 | 35 – 1002 |
| Manganese | 0.4 | 0.2 | 0.6 | 4.0 | 3.3 | 4.8 | 10 – 502 |
| Selenium | 0.1 | 0.01 | 0.1 | 3.7 | 49.8 | 1.6 | < 11 |
| Phosphorus | 75.1 | 176.2 | 125.2 | - | - | - | 0.1 – 0.21 |
| References | Tokusoglu and Uunal, 2003 | Debbarma et al., 2016 | Allen et al., 2001 | ||||
Represent %.
ppm.
However, the optimal dosage, frequency, and combination of these supplements may vary depending on poultry species, breed, age, and production system. Challenges and limitations in using algae and seaweed as feed supplements include their high fiber, phenolic, and ash content, variable availability and quality, high production and processing costs, and potential toxicity or allergenicity. Further research is necessary to evaluate the effects of algae and seaweed on poultry health and performance under various conditions to fully unlock the potential of algae and seaweed in poultry nutrition.
By-Products and Food Waste Utilization
By-products and food waste are often overlooked resources. It can come from the food production, processing, distribution, and consumption chain. For example, remnants from the fruit juice sector constitute a rich source of dietary fiber, antioxidants, vitamins, minerals, and phytochemicals capable of contributing to poultry well-being (Ominski et al., 2021; Georganas et al., 2023). Similarly, by-products stemming from the oilseed industry (soybean, canola, sunflower, cottonseed, and flaxseed meals or cakes) provide valuable components such as protein, amino acids, fatty acids, and minerals that are highly beneficial for poultry nutrition (Georganas et al., 2023). Distillers' grain by-products (dried grains with solubles and wet grains) from corn or wheat ethanol production (Swiatkiewicz and Koreleski, 2008) provide essential nutrients like protein, energy, fiber, and phosphorus. Most significantly, this approach contributes to mitigating the environmental impact of poultry production by reducing greenhouse gas emissions, water consumption, land utilization, and waste generation (Ominski et al., 2021; FAO, 2023b). Moreover, the waste products generated by poultry (manure and litter) can serve as valuable fertilizer sources for farms and vegetable cultivation. Likewise, ammonia produced within poultry housing facilities can be captured and repurposed as a potential energy source.
Integrating this waste into poultry diets reduces reliance on expensive conventional feed ingredients (Truong et al., 2019) and improves product quality by providing functional components (Ominski et al., 2021; Georganas et al., 2023). Despite these advantages, several challenges and limitations must be addressed before considering the utilization of by-products and food waste. Regulatory restrictions exist for certain types of food waste due to concerns about disease transmission and contamination (Ominski et al., 2021; FAO, 2023b). Safety concerns revolve around the quality and stability of food waste, such as microbial spoilage, chemical residues, toxins, or anti-nutritional factors. These could impact poultry health and performance. Moreover, incorporating by-products and food waste into poultry diets presents logistical complexities related to the collection, transportation, storage, and handling of such materials. These challenges encompass availability, variability, cost-effectiveness, processing methodologies, preservation approaches, and feed formulation intricacies (Ominski et al., 2021; FAO, 2023b). A comprehensive evaluation of their composition, digestibility, bioavailability, functionality, and acceptability is imperative to ensure effective and sustainable utilization.
WASTE MANAGEMENT AND RESOURCE EFFICIENCY
Effective waste management and resource efficiency are integral components of sustainable poultry farming. Properly handling and utilizing poultry waste can mitigate environmental pollution, conserve resources, and even generate additional benefits for the farm. This section explores various waste management strategies and resource-efficient practices in poultry farming.
Composting and Manure Utilization
Effectively managing the large volume of manure from poultry farming remains a critical challenge leading to environmental pollution, greenhouse gas emissions, and noxious odors (Chai et al., 2018; Bist and Chai, 2022; Bist et al., 2023b, g). Therefore, implementing waste management practices is paramount to ensure the sustainability of poultry farming operations. Composting is a widely adopted and efficient method for addressing this challenge and converting poultry manure into a valuable organic fertilizer (AgriFarming, 2023b). The controlled decomposition process involves manure and organic materials to yield a nutrient-rich compost, reduce pathogens, and eliminate odors. Applying the compost to croplands fosters a closed-loop system that aligns with circular economy principles. Furthermore, composting reduces manure volume and minimizes storage, transportation, and costly waste disposal. Composting also reduces odorous emissions, including ammonia and methane (Kumari et al., 2022).
Biogas Production and Energy Generation
Biogas production and energy generation constitute pivotal facets of sustainable poultry farming practices (Figure 6). It emerges as a renewable and environmentally friendly energy source (Vaarst et al., 2015; Reporter, 2020). Derived from anaerobic digestion, a process facilitated by microorganisms breaking down poultry litter and organic waste without oxygen. The utilization of poultry waste for biogas production carries a dual benefit: waste reduction and renewable energy generation. Methane is the biogas primary output and energy source (Pecar and Gorsek, 2020). Methane can be effectively used for various purposes like electricity generation, cooking, and clean-burning fuel for heating (Kapoor et al., 2020). An additional environmental advantage of this process lies in its potential to mitigate greenhouse gas emissions (mainly methane) and possesses a significantly higher global warming potential than conventional gas (Howarth et al., 2011). Furthermore, anaerobic digestion produces a nutrient-rich material (digestate) suitable as fertilizer or soil conditioner (Muduli et al., 2018). In addition, poultry farms can reduce energy consumption, renewable energy use, and environmental impact by implementing biogas production systems. Composting and anaerobic digestion are sustainable waste management practices that provide economic benefits and reduce the poultry industry's environmental footprint.
Figure 6.
Utilizing Waste Poultry Products for Biogas Production and Sustainable Energy Generation.
Biogas can also be a valuable resource in its upgraded form as biomethane. Biomethane boasts a higher energy content and can be injected into the natural gas grid or used as a vehicle fuel (Patrizio et al., 2015; Atchike et al., 2022). Energy generation from biogas can be used to operate various machines like gas engines, gas turbines, microturbines, fuel cells, and boilers (Kapoor et al., 2020). Furthermore, biogas-based energy generation offers a reliable and decentralized energy source, particularly beneficial for rural and remote areas. It diversifies the energy portfolio and enhances overall energy security (Reporter, 2020). Biogas production enhances productivity and profitability through reduced reliance on external energy sources and income diversification. To implement biogas systems successfully, challenges must be addressed, including feedstock availability, efficient system design, effective biofertilizer management, and regulatory support (Khoshnevisan et al., 2021).
Solar Power
Integrating solar power within poultry housing is paramount to achieving sustainability in the poultry farming sector (Figure 7). Solar power generates clean, cost-effective electricity from the sunlight and reduces reliance on traditional non-renewable energy sources (Chel and Kaushik, 2011). Solar power lowers operational costs, enhances energy efficiency, and reduces greenhouse gas emissions. Transitioning to renewable energy ensures reliable power for essential operations and supports global efforts to combat climate change. Solar power is crucial to fostering responsible and environmentally conscious agriculture while securing a more sustainable future for industry.
Figure 7.
Solar technology for the poultry industry.
Water Conservation and Reuse
Water conservation and reuse are essential components of sustainable poultry farming, given the growing global concern regarding water scarcity (Rehman et al., 2022). Water-efficient practices deliver substantial advantages, benefiting the environment and bolstering the economic viability of poultry operations. Strategies like rainwater harvesting and water recycling are instrumental in reducing water usage on poultry farms and processing plants. Rainwater harvesting involves collecting and storing rainwater from various surfaces and diminishing reliance on scarce or polluted freshwater sources (Tzanakakis et al., 2020). Furthermore, using automated water systems and effective management practices like water recycling can address the challenges of water scarcity in poultry farming (Matsumura and Mierzwa, 2008; Avula et al., 2009; Tarantino, 2023). These systems treat and repurpose wastewater from various farm and processing plant activities. Doing so can reduce the demand for fresh water in poultry operations and prevent the release of contaminants into the environment. Modern technologies and commercial housing design have reduced the significant use of water. The National Chicken Council reports that from 1965 to 2019, water consumption, land use, greenhouse gas emissions, and resources required for poultry have decreased by 58, 72, 36, and 75%, respectively (National Chicken Council, 2019).
Despite the evident advantages of water conservation and reuse, certain challenges need to be addressed to ensure their successful implementation. These challenges include affordable water management technologies, adaptable systems for varying water sources, and rigorous maintenance to ensure quality and safety standards (Rehman et al., 2022). In addition, supportive regulations and policies like incentives, subsidies, permits, or certification schemes are necessary. Poultry farmers can enhance sustainability and responsibly use finite resources by addressing these challenges and adopting water-efficient practices.
Integration With Crop Farming and Circular Economy
Integrating poultry farming with crop production is a practical approach to achieving sustainability and circular economy principles (Rauw et al., 2023). Poultry and crops coexist harmoniously by reducing waste and optimizing resource utilization. Integration helps to enhance soil fertility and crop growth using poultry manure as a natural fertilizer. Poultry manure improves soil quality, water retention, and nutrition (Dikinya and Mufwanzala, 2010). Additionally, it reduces reliance on chemical fertilizers, pesticides, and feed by utilizing locally available resources like crop residues, food waste, and insects. Thus, reusing can reduce production costs and environmental impact. Furthermore, a circular economy diversifies income sources and enhances food security through poultry products (meat, eggs, feathers, and by-products) and crop yields (grains, fruits, vegetables, or fodder). Lastly, it promotes biodiversity and ecosystem services by creating diverse habitats for plants, animals, and microorganisms, contributing to increased pollination, pest control, carbon sequestration, and water purification (Rehman et al., 2022).
Combining poultry and crop farming presents complex challenges in effectively managing and coordinating various aspects like planting, harvesting, feeding, housing, and processing. These demand expertise and infrastructure to be successful in this field. In addition, ensuring the health and welfare of crops and poultry requires effective management of diseases, parasites, predators, and pests through biosecurity measures such as fencing, sanitation, vaccination, or treatment. Similarly, regulatory and policy support is crucial to encourage farmers to adopt sustainable practices and consumers to support sustainable products.
ENHANCING POULTRY WELFARE
Ensuring the welfare of poultry is not only an ethical responsibility but also a critical aspect of sustainable poultry farming. Prioritizing animal welfare improves birds' health and performance (Bist et al., 2023a), which leads to more productive and healthy flocks. The unacceptable suffering of animals in husbandry systems is an ethical concern. Therefore, ensuring a life without suffering aligns with sustainability perspectives, including social and environmental aspects (WOAH, 2017; Rojek, 2023). The EU's welfare protection project established criteria for animal welfare, emphasizing promoting positive emotions and avoiding negative ones (Rojek, 2023). Some current poultry-rearing methods, such as fast growth, lead to leg issues, compromising animal welfare and causing abnormal behaviors (Bessei, 2006). Regardless of the definition, poultry are living beings deserving protection and opportunities for a life worth living.
Housing and Enrichment Practices
The poultry's well-being is profoundly influenced by the conditions of their housing environment, a fundamental aspect of sustainable poultry farming (Vaarst et al., 2015). The housing facility design must consider the birds' comfort and safety with ongoing monitoring and adaptability of behaviors (Bist et al., 2023f; Subedi et al., 2023a; Yang et al., 2023c). It requires adequate housing and enrichment practices that promote the welfare of birds, addressing their physical and mental well-being, health, comfort, behavior, and productivity. Housing systems (free-range, cage-free, and enriched cages) play a pivotal role in allowing poultry to exhibit their natural behaviors, such as foraging, dust bathing, and perching (Rodenburg et al., 2020). The comparative assessment of poultry welfare and performance across different housing systems indicates that alternative systems like aviaries and litter floor setups offer significant advantages. These systems allow for more natural behaviors, lower stress levels, and improved health and bone quality compared to conventional cages (Table 5). Additionally, they tend to perform better in terms of egg production and feed efficiency. In contrast, conventional cages show limitations in promoting poultry welfare and achieving optimal production outcomes. These findings emphasize the need to transition towards more welfare-conscious poultry farming housing systems to improve well-being.
Table 5.
Comparative poultry welfare and performance assessment across different housing systems.
| Parameters | Conventional cage | Furnished cage | Aviaries | Litter floor | Free-range |
|---|---|---|---|---|---|
| Behavioral Expressions (%) | |||||
| Walking | ⁎⁎ | ⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Drinking | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Feeding | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Foraging | * | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ |
| Dustbathing | * | ⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Nesting | * | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Perching | * | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ |
| Feather pecking or cannibalism | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Fearfulness1 | ⁎⁎ | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎ |
| Heterophil/Lymphocyte ratio (Stress) | ⁎⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ |
| Smothering | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎ |
| Health and bone quality | |||||
| Skeletal quality | ⁎⁎ | ⁎⁎⁎ | ⁎⁎ | ⁎⁎ | ⁎⁎ |
| Footpad dermatitis | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎ | ⁎⁎ | ⁎⁎ |
| Claw length (mm) | ⁎⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎ |
| Keel Bone fracture | ⁎⁎ | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ |
| Bone breaking strength | ⁎⁎ | ⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ |
| Breast blister | ⁎⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎ | ⁎⁎ | ⁎⁎ |
| Performance and production (%) | |||||
| Mortality | ⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎ |
| Feed conversion ration | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Dirty egg ratio | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Damaged egg ratio | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎ |
| Diseases outbreak | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Hen day egg production | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Feed Intake (g) | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ | ⁎⁎⁎⁎ |
| Egg mass (g) | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ |
| Body weight (g) | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ |
| Feather score2 | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎ | ⁎⁎⁎⁎ |
None or incomplete.
Relatively low.
Moderate or normal.
Full or relatively high based on health, production, behavior, and welfare condition according to housing system.
Tonic immobility duration in second.
Feather score based on 1-4. References: (Reece et al., 1971; Fossum et al., 2009; Lay Jr et al., 2011; Wilkins et al., 2011; Bilal et al., 2014; Yilmaz Dikmen et al., 2016).
Castellini et al., 2006 conducted a comprehensive analysis to assess sustainability concerning food needs, environmental conservation, economic viability, and quality of life. They compared 3 poultry production systems: conventional, organic, and organic-plus (featuring stricter standards for animal welfare and meat quality). The Organic-plus system emerged as the top performer when considering economic, social, and environmental aspects based on criteria from scientists and consumer stakeholders. The organic system is more sustainable than conventional poultry production. Despite lower annual productivity, it uses fewer external inputs, saves energy, and has better resource efficiency (Castellini et al., 2006). Comparing organic and conventional poultry production systems reveals significant differences. Organic farming, emphasizing eco-friendly practices and avoiding chemicals, lowers energy costs, particularly crop production. Despite lower annual productivity, organic poultry demonstrates higher input efficiency and showcases greater sustainability with a smaller environmental impact. The main disparities between organic and conventional poultry production are feed and cleaning costs. Poultry feed accounts for over 50% of energy consumption in both systems, but organic crops save around 60% of energy due to no chemical fertilizer use (Castellini et al., 2006). Housing costs remain similar. Despite lower annual productivity (-206%) than conventional, organic poultry exhibits a 10% lower transformity, indicating improved efficiency. Overall, organic poultry is more sustainable, offering enhanced efficiency, increased use of renewable inputs, reliance on local resources, and reduced energy and material intensity.
Enrichment practices in poultry farming can vary depending on factors like the production system's type, scale, and location. However, general principles can significantly elevate poultry welfare, including ensuring adequate space, ventilation, lighting, and temperature control to enable birds to express their natural behaviors (Baker and Steemers, 2019) while preventing stress, heat stress, overcrowding, or injuries. Maintaining clean and dry litter, bedding, or flooring for resting, dust bathing, scratching, or foraging is crucial. Providing access to outdoor areas like pastures, orchards, or agroforestry systems gives birds fresh air, sunlight, vegetation, and opportunities to forage for insects. Providing appropriate feeders, drinkers, nests, perches, and roosts meets birds' nutritional, physiological, and behavioral requirements. Diverse forms of environmental enrichment, such as perches (Bist et al., 2023a), toys (Tahamtani et al., 2022), pecking blocks (Liebers et al., 2019; Bist et al., 2023d), straw bales, branches, or mirrors (Jacobs et al., 2023), encourage curiosity, exploration, and social interactions among them. In addition, enrichment practices, such as providing objects for pecking and exploration, actively engage the cognitive and physical abilities of the birds, reducing stress and promoting their overall welfare (Campbell et al., 2019). Protecting the birds from predators, parasites, diseases, and extreme weather conditions is imperative and involves using appropriate fencing, netting, shelters, sanitation, vaccination, or treatment.
Sustainable housing and management practices provide various advantages to elevating productivity and profitability by mitigating issues like mortality, morbidity, feather pecking, cannibalism, or feed wastage. Previous research studies have shown the positive effects of housing and enrichment practices on various facets of poultry production. For example, Campbell et al., 2020 found that free-range systems with outdoor access improved hen welfare, reducing feather damage and stress responses. Azevedo (2020) reported that integrating chickens into agroforestry systems enhanced chicken welfare, increasing activity levels, foraging behavior, and plumage conditions. Similarly, Riber et al., 2018 discovered that environmental enrichment practices reduced fearfulness and aggression among broiler chickens without compromising growth, feed conversion ratio, or carcass quality. Furthermore, they enhance the quality and safety of poultry products by reducing contamination, bruising, or downgrading. Meeting ethical standards and animal welfare certifications in poultry production can increase consumer satisfaction and demand for poultry products (Vanhonacker and Verbeke, 2009; Martinez Michel et al., 2011). Despite these benefits, challenges persist in the accessibility and affordability of suitable technologies and equipment for housing and enriching poultry and the effective management and monitoring of these practices.
Behavior-Based Management Approaches
Behavior-based management approaches are integral methods that consider poultry's inherent behavior, requirements, and preferences, allowing them to express their natural tendencies. These approaches find application across various facets of poultry production, encompassing housing, feeding, handling, transport, and even slaughter processes. Behavior-based management strategies revolve around a profound understanding of poultry behavior, aiming to address the underlying factors driving specific behaviors. Farmers can discern potential stressors or environmental challenges that might compromise the birds' welfare through careful observation and interpretation of bird behavior. For instance, aggressive pecking within flocks may signify issues related to social hierarchy, while feather pecking might signal the need for environmental enrichment or adjustments in nutrition (Subedi et al., 2023a; Bist et al., 2023d). Farmers can implement targeted interventions by adopting behavior-based management, fostering an environment conducive to positive behaviors, and reducing stress. Strategies like low-density feed have been explored to reduce hunger and frustration in broiler breeders, promoting comfort behaviors (Riber, 2020). Taking a proactive stance in welfare management empowers poultry farmers to enhance birds' well-being and curtail harmful behavioral patterns.
Researchers have demonstrated that behavior-based management approaches provide several advantages to improve poultry welfare. Baxter et al., 2019 demonstrated that environmental complexity, including structural enrichment like straw bales or platforms, increased broiler chicken activity levels, exploration, and space utilization while reducing fearfulness, aggression, and injurious pecking. It can reduce stress, frustration, boredom, and aggression in poultry by enabling them to engage in normal behaviors like foraging, dustbathing, perching, nesting, and socializing (El-Lethey et al., 2000; Bist et al., 2023d; Yang et al., 2023c). Similarly, Riber et al., 2018 revealed that providing laying hens with dietary choices positively impacted feeding motivation, foraging behavior, and feather condition without adversely affecting performance, egg quality, or feed intake. Additionally, these approaches improve poultry health and immunity by preventing or mitigating injuries, infections, diseases, or mortality from abnormal behaviors such as feather pecking, cannibalism, or stereotypes. It also aligns with ethical standards and animal welfare certifications, elevating consumer satisfaction and demand for poultry products.
Health Management and Disease Prevention
Health management and disease prevention are fundamental aspects that should be considered to enhance poultry welfare and sustainability. These approaches ensure that birds are raised in conditions that prioritize their well-being and minimize suffering. Through robust biosecurity measures, vaccination protocols, and hygiene practices, poultry farmers can protect their flocks from the harmful effects of disease outbreaks (Damerow, 2016). Moreover, proactive veterinary care for sick or injured birds minimizes suffering, prevents disease spread (Merck, 2012), and enhances bird health. Proper housing with adequate ventilation, lighting, and temperature control reduces stressors like heat stress, overcrowding, and injuries (Abo-Al-Ela et al., 2021; Vandana et al., 2021). In addition, providing birds access to outdoor areas where they can bask in fresh air, sunlight, vegetation, and insects significantly enriches their well-being. Aligning poultry farming with ethical standards and animal welfare certifications strengthens its contribution to environmental sustainability by reducing pollution and greenhouse gas emissions and optimizing resource usage. Thus, health management and disease prevention are crucial for pursuing poultry sustainability.
Genetic Selection for Welfare Traits
Genetic selection helps to enhance the welfare of poultry. Selecting birds with calm temperaments, robust immune systems, and adaptability to different environments can lead to healthier flocks. Modern breeding programs balance production traits and welfare attributes to ensure birds thrive in various production systems (EFSA Panel on Animal Health and Welfare, 2010; Brito et al., 2020; Hartcher and Lum, 2020). Genetic advancements also address issues like skeletal health and leg strength to reduce the incidence of leg disorders (Muir and Aggrey, 2003; Peixoto et al., 2020). The poultry industry can continue to improve bird welfare through selective breeds to ensure the long-term sustainability of poultry farming. EC Regulation 834/2007 and Animal Health and Welfare in Organic Agriculture (Hovi et al., 2003) recommend utilizing native breeds for their resilience and suitability for outdoor environments. These native breeds grow slower and exhibit greater vitality, disease resistance, and adaptability to outdoor conditions (Castellini et al., 2009).
Genetic selection aims to enhance poultry adaptability and resilience to diverse environments and production conditions by prioritizing health, behavior, and well-being traits. These traits include immune response, disease resistance, feather quality, activity level, and foraging behavior. Selecting the best quality traits can handle various production systems' challenges, ultimately improving welfare outcomes (Brito et al., 2020; Hartcher and Lum, 2020). It can reduce stress, fear, frustration, boredom, and aggression in poultry by allowing them to perform normal behaviors (Muir et al., 2014). This approach enhances bird well-being and boosts their health and immunity, preventing injuries, infections, diseases, or mortality due to genetic defects or environmental factors. Additionally, it can improve the productivity and quality of poultry by increasing growth, feed efficiency, egg production, or hatchability (Pym, 2013).
IMPACT OF GENETICS AND BIOTECHNOLOGY
Genetics and biotechnology in poultry farming have revolutionized the industry, boosting sustainability, productivity, and animal welfare. These technologies manipulate genes and molecules in living organisms for a more efficient approach to poultry farming (Muir and Aggrey, 2003). Genomic selection empowers breeders to identify and choose poultry with desirable traits based on their genetic makeup. By examining the entire genome of individual birds, breeders can accurately predict their performance in traits like growth rate, feed efficiency, disease resistance, and reproduction (Thiruvenkadan et al., 2011). Genomic selection accelerates genetic improvements to develop poultry better suited for sustainable production environments like free-range or pasture-based systems (Castro et al., 2023). In addition, genetic diversity is crucial for ensuring that poultry populations are adaptable to changing environments and resilient to emerging diseases (Thiruvenkadan et al., 2011; Castro et al., 2023). Therefore, preserving indigenous or rare breeds recognizes their possession of unique and valuable traits tailored to specific production systems (Vaarst et al., 2015). Using heritage breeds boosts cultural and agricultural diversity and reduces the risk of inbreeding depression, improving productivity and health. Collaborative efforts involving active breeding programs and partnerships with conservation organizations are instrumental in championing the cause of genetic diversity in poultry populations (Wurzinger et al., 2021). Therefore, this technology is important in safeguarding rare or valuable genetic traits and significantly contributes to preserving genetic diversity within poultry populations.
With these genetic advancements, the poultry industry faces challenges concerning antibiotic use (Cervantes, 2015; Haque et al., 2020). Chickens have frequently been given antibiotics for disease prevention, treatment, and growth enhancement, leading to concerns about antibiotic resistance. Antibiotic-free poultry production has gained more attention due to consumer perceptions of its superiority despite a scarcity of robust scientific evidence (Smith-Spangler et al., 2012). Antibiotic-free poultry production in the United States means stopping all antibiotic use on farms and using synthetic anticoccidials, live coccidiosis vaccines, or drug rotations to prevent disease (Cervantes, 2015). However, this approach faces challenges such as synthetic anticoccidial resistance in coccidia, lack of antibiotic effects in preventing necrotic enteritis, and potential harm to bird intestinal health (Al-Sheikhly and Al-Saieg, 1980). Additionally, antibiotic-free production tends to be less efficient, resulting in an amplified carbon footprint (Cervantes, 2015). Companies choosing antibiotic-free poultry must be prepared to navigate these complexities related to bird health, production efficiency, and cost. A major focus in this field should be the development of genetically engineered poultry with improved traits (Sid and Schusser, 2018). For instance, genetically modified birds with improved disease resistance or altered nutritional profiles hold the promise of reduced antibiotic use and enhanced product quality. However, deploying genetically engineered poultry necessitates meticulous consideration of ethical, environmental, and regulatory dimensions to ensure responsible innovation.
PRECISION POULTRY FARMING TOWARD SUSTAINABILITY
Precision poultry farming (PPF) marks a significant shift in the poultry industry (Berckmans, 2014; Bist et al., 2023f; Guo et al., 2023; Neethirajan, 2023; Yang et al., 2023a; Subedi et al., 2023b) by offering innovative solutions to enhance sustainability and efficiency. It utilizes real-time data from sensors, cameras, and monitoring devices to optimize various critical aspects of poultry farming (Table 6) (Bist et al., 2023f; Lu et al., 2023; Neethirajan, 2023). Precision poultry farming has a pivotal role in promoting poultry welfare and health. Continuous monitoring and interpretation of data from various sources (Guo et al., 2023; Subedi et al., 2023a; Bist et al., 2023e; Yang et al., 2023c) enable early detection of disease or stress within poultry flocks. This proactive health management approach reduces the need for antibiotics and other medications, improving bird well-being and ensuring healthier poultry products. Additionally, precision poultry farming empowers farmers with data-driven decision-making capabilities. Farmers can optimize resource allocation, supply chain management, and production processes through advanced analytics, effectively minimizing inefficiencies and waste. An example is precision feeding, where individual birds' or flocks' precise feeding schedules and quantities are tailored using data-driven insights (Brossard et al., 2017; Zuidhof et al., 2017). It helps to significantly reduce feed waste, enhances feed efficiency, and concurrently minimizes the environmental footprint linked to excessive feed production and waste disposal. This approach benefits poultry operations and broader sustainability goals by reducing resource use and environmental impact.
Table 6.
Precision monitoring technologies for enhancing poultry sustainability in poultry farming.
| Poultry Species | Housing type | PPF methods/Models | PPF tools | Measured parameter | Results | References |
|---|---|---|---|---|---|---|
| Broilers | 30-gallon chamber | Cervical dislocation, water-based foam, and polyethylene tent procedure were used. | Accelerometer in the wing, leg, and neck. ECG electrodes attached to measure heart rates |
Cessation of activity to monitor broiler and to determine time to death | Cessation of activities was measured, and a new depopulation method | Dawson et al., 2007 |
| Broilers | Commercial broiler farm | The data-based mechanistic model uses broiler activity and ventilation rate. | Camera, DustTrak device | Real-time indoor particulate matter (PM) | Potential to measure real-time PM | Fernandez et al., 2019 |
| Broilers | Broiler pen house | Bio-acoustics data recording and analyzed using sneeze detection algorithm. | SOMO + SoundTalks device plugged to microphone | Sneeze detection | Sensitivity of 66.7% and precision of 88.4% to detect sound as sneeze or no-sneeze | Carpentier et al., 2019 |
| Laying hens | Cage-free floor raised | Real-time and automatic detection of hens using different YOLOv5-hens model | Camera | Detect floor hens | Overall accuracy more than 95% | Yang et al., 2022 |
| Broilers | Broiler pen house | DeepLabCut and Graphical user interface | Web camera, RGBD camera | Spatiotemporal and three-dimensional locomotive behavior using a three-point gait scoring system | Training model got an accuracy of 100% and root mean square error of 3.62 ± 2.71 mm | Li et al., 2023 |
| Broilers | Broiler pen house | Support vector machines and artificial neural networks used as model classifiers | Thermal and normal camera | Detect Newcastle disease (ND) and Avian Influenza (AI) | Accuracy to classify AI by 97.2% and ND by 100% | Sadeghi et al., 2023 |
| Brown hens | Aviary | Automatic monitoring of hens in floor using YOLOv5 models with different configurations. | Camera | Monitor and detect hens | Detection precision was 98.2%, recall 92.9%, and mAP_0.50 96.7% | Guo et al., 2023 |
| Laying hens | Cage-free floor raised | Monitor applied behaviors using multiple CNN models | Camera | Detect and classify 6 behaviors like feeding, drinking, walking, perching, dustbathing, and nesting | Received accuracy up to 95.3% | Yang et al., 2023c |
| Laying hens | Cage-free floor raised | Segment anything model (SAM) used to segment hens. | Normal and thermal camera | Explore hen tracking | SAM lays a foundation for hen segmentation and tracking | Yang et al., 2023d |
| Laying hens | Cage-free floor raised | Spatial distribution of hens using YOLOv5 model | Camera | Spatial distribution of laying hens on floor in detecting perching, feeding, drinking, and other behaviors | Performance in detecting spatial distribution and behavior detection was obtained upto 94.2% | Yang et al., 2023b |
| Laying hens | Cage-free floor raised | Computer vision-based model using two-stage and single-stage model | Normal and thermal camera | Egg grading based on 5 egg sizes and defect detection into 5 categories | Accurately detected egg and graded by 94-96%. | Yang et al., 2023a |
| Laying hens | Cage-free floor raised | Machine vision-based YOLO models to detect floor eggs | Camera | Floor egg detection | Accurately detected floor eggs by 92.1% | Subedi et al., 2023b |
| Laying hens | Cage-free floor raised | YOLOv5 model used to detect pecking behavior | Camera | Detect pecking behavior | Yolov5 pecking model results in an accuracy of 78.7% | Subedi et al., 2023a |
| Laying hens | Cage-free floor raised | Deep learning technology used the YOLOv5 model to detect mislaying behavior | Camera | Detect mislaying behavior, which was the leading cause of mislaid eggs | Detected accurately for different numbers of mislaying behaviors up to 99.6% | Bist et al., 2023f |
| Laying hens | Cage-free floor raised | Novel YOLOv6 object detectors used to detect piling behaviors | Camera | Monitor and detect piling behaviors | Piling behavior detected with a mAP_0.50 of 98.9% | Bist et al., 2023c |
| Laying hens | Cage-free floor raised | YOLOv5 and YOLOv6 models used to detect dead hens on floor | Camera | Detect hen mortality | Mortality detection mAP_0.50 was 99.4% | Bist et al., 2023e |
mAP- mean average precision.
Furthermore, precision poultry farming extends to genetic selection programs that facilitate poultry breeding with desirable traits. Precision farming can identify and prioritize genetic markers associated with these advantageous traits by analyzing comprehensive poultry genetics and performance datasets (Doran et al., 2017; Park et al., 2020). This informed breeding process leads to more sustainable poultry breeds requiring fewer resources and increasing production outcomes. Furthermore, precision poultry farming is pivotal in waste management and energy efficiency (Zhao et al., 2022). It automates waste removal, optimizes energy consumption through real-time control of ventilation systems and lighting, and aids in detecting diseases or anomalies that may disrupt efficient poultry farming. The multifaceted contributions of precision poultry farming collectively pave the way for a more sustainable and environmentally responsible future for the poultry industry.
ECONOMIC VIABILITY AND MARKET OPPORTUNITIES
Ensuring the economic viability of sustainable poultry farming practices is essential for their widespread adoption and long-term success. This section discusses the economic aspects of sustainability, covering cost-benefit analyses, government policies and incentives, and market trends that benefit sustainable poultry producers.
Cost-Benefit Analysis of Sustainable Practices
Conducting a thorough cost-benefit analysis tailored to specific production systems and market contexts is vital for poultry farmers (Cui et al., 2021). It helps in assessing the financial feasibility of sustainable poultry farming practices (Vaarst et al., 2015). While implementing this sustainability goal involves initial costs or operational investments, the long-term benefits often greatly surpass these expenses. For example, using energy-efficient equipment or renewable energy sources can significantly reduce utility bills and provide substantial long-term savings (Herzog et al., 2001; Cui et al., 2021; Zikhali et al., 2023). Waste management strategies such as composting reduce disposal costs while supplying valuable organic fertilizer for crops. Similarly, improved animal welfare can enhance bird performance and decrease stress-related losses, contributing to economic gains. Additionally, meeting consumer demands for ethically produced and environmentally friendly poultry products can open up premium market opportunities and strengthen a farm's competitive position. One promising sustainable poultry practice is the using insect-based feeds, which can replace up to 20% of fish meal without compromising the bird growth performance (Waithaka et al., 2022). This approach reduces feed costs and lessens the environmental impact of poultry production. Moreover, integrating renewable energy technologies like solar panels, wind turbines, and heat pumps can significantly cut energy consumption and greenhouse gas emissions in poultry farming (Cui et al., 2021; Li et al., 2022; Waithaka et al., 2022). However, the feasibility and suitability of these technologies may vary depending on specific farm conditions and objectives.
Government Policies and Incentives
Government policies and incentives include measures to support, regulate, or influence sectors like agriculture, aiming for economic growth, environmental improvement, food security, and social welfare (USDA, 2021). The USDA's pledge to invest $500 million from the American Rescue Plan in expanding meat and poultry processing aims to offer farmers, ranchers, and consumers more choices in the market. Additionally, over $150 million has been allocated to support small and very small processing facilities, helping them overcome COVID-19 challenges, remain competitive, and reach a wider customer base. At the same time, incentive programs like grants, subsidies, and tax incentives are crucial in easing the financial challenges of implementing sustainable practices (USDA, 2021; UK, 2023). Furthermore, support for research and extension services empowers farmers with the requisite knowledge and technical acumen, facilitating a seamless transition towards sustainable methodologies. Moreover, regulatory measures emphasizing animal welfare, environmental protection, and responsible resource management create an equitable landscape for sustainable poultry producers. Compliance with sustainability standards may evolve into a prerequisite for market access or participation in certification schemes, offering additional impetus for farmers to embrace sustainable methodologies (USDA, 2021). The UK has been at the forefront of promoting sustainability within its agricultural sector, offering incentives such as grants for waste management initiatives to reduce the environmental impact of poultry waste and generate additional income or products (UK, 2023). Similarly, the institutional facets of sustainability involve governing global systems marked by accountability, transparency, and inclusivity of members and representatives. However, the current food system faces challenges because a few large breeding companies dominate, making it difficult for smaller, sustainable-focused entities to establish themselves. Additionally, the effective governance of these systems hinges upon the delicate equilibrium of diverse interests inherent within the sustainability concept, necessitating adept management. Collaborative and adaptive governance processes are instrumental in navigating these intricacies, facilitating the poultry sector's transition towards a more sustainable and inclusive trajectory.
Market Trends and Consumer Preferences
Market trends characterized by demand, supply, and pricing dynamics shifts increasingly align with consumer preferences for sustainable and ethically produced poultry products. This convergence is driven by heightened consumer awareness of their food choice's environmental and ethical implications (Carter, 2007; Verbeke, 2009; Animal Welfare Institute, 2019; National Chicken Council, 2019; Hafez, 2020). One prominent market trend is the soaring global demand for poultry products, anticipated to grow demand for eggs by 64% (Yitbarek, 2019) and meat by 73% (including other livestock) by 2050 (FAO, 2011). This growth is attributed to increased population, urbanization, incomes, and evolving dietary patterns (Mottet and Tempio, 2017; FAO, 2023a). Concurrently, consumers increasingly prefer poultry items that focus on environmental sustainability and ethical practices. Consumer preferences are increasingly influenced by concerns about poultry production's environmental and social impacts (Van Loo et al., 2010; Martinez Michel et al., 2011). Consumers seek transparency in the production process, particularly emphasizing issues like pollution, greenhouse gas emissions, resource conservation, animal welfare, and health risks associated with poultry farming. Additionally, consumers clearly prefer locally sourced and organic poultry products, perceiving them as fresher, healthier, tastier, and more environmentally and animal friendly (Harper and Makatouni, 2002; Vaarst et al., 2015; National Chicken Council, 2019). This preference extends to a willingness to pay a premium for such products, recognizing their benefits to local farmers and communities (Van Loo et al., 2010; Martinez Michel et al., 2011). In response, poultry producers are increasingly aligning their practices with these preferences to meet the rising demand for ethically and sustainably produced poultry items, positioning themselves for success in a socially responsible food industry.
LIMITATION AND CHALLENGES TO ADOPTION
Sustainable poultry farming has many benefits but faces several challenges to becoming widespread. This section explores the challenges, such as technical barriers, economic challenges, knowledge gaps, and the need for strong policies and support.
Technical and Technological Barriers
Technical and technological barriers present a significant challenge in adopting new practices and technologies (Teklewold et al., 2006). These barriers include availability, accessibility, affordability, adaptability, and acceptability. A major challenge is specialized infrastructure and management for housing like free-range systems or mobile poultry units. Farmers often face challenges updating existing facilities or investing in new equipment and technology (Rodriguez et al., 2009). Another obstacle is farmers' lack of technical knowledge and expertise (Rodriguez et al., 2009). To overcome these technical barriers, it is crucial to equip farmers with essential skills, knowledge, and support from agricultural experts and extension services. Moreover, challenges arise from the difficulty of making new techniques and technologies fit local conditions, needs, preferences, and traditions. When adopting these innovations, Farmers might face technical issues, environmental constraints, social conflicts, or cultural resistance (Rodriguez et al., 2009). To address these complex challenges effectively, adopting participatory approaches, implementing adaptive management strategies, engaging stakeholders, and educating consumers are crucial.
Economic and Financial Challenges
Sustainable poultry farming aims to reduce environmental impact and improve economic viability but faces several economic and financial challenges. One significant barrier lies in the higher initial investment and operational costs (Teklewold et al., 2006; Rodriguez et al., 2009; Tate et al., 2014). Infrastructure and technologies like renewable energy systems, advanced waste management, and improved animal welfare facilities require significant upfront costs, potentially affecting poultry farms’ budgets. Despite the long-term benefits of sustainable practices (Wu et al., 2017), farmers often face financial challenges managing cash flow during the transition period. Access to dedicated financing, loans, or grants tailored to support sustainable practices is crucial to addressing these financial burdens (Rodriguez et al., 2009). Government initiatives, such as financial incentives, grants, or tax breaks for sustainable farming, need to encourage farmers to invest in more sustainable systems (USDA, 2021). Farmers need assurance that their investments will yield economic and environmental benefits over the long term. Moreover, the market competitiveness and consumer demand for sustainable poultry products vary regionally, influenced by pricing and product quality factors. To address these challenges, potential solutions include seeking financial support from governmental programs, NGOs, or private investors that offer grants, loans, or equity for sustainable poultry farming projects. Creating local networks and partnerships with stakeholders such as farmers, processors, retailers, and consumers dedicated to sustainable poultry production and consumption can enhance resilience against economic challenges.
Knowledge and Awareness Gaps
Sustainable poultry farming faces knowledge and awareness gaps that affect widespread adoption. Farmers in remote or less accessible communities limit access to information and best practices. Promoting awareness and sharing knowledge through workshops, training programs, and platforms for exchanging information is necessary (Timmons, 2009; Global Poultry, 2023). Additionally, there is often a lack of information available to poultry farmers regarding the associated costs and benefits (Vaarst et al., 2015; Wu et al., 2017; Cui et al., 2021). Many farmers may not be aware of the benefits of reducing greenhouse gas emissions, improving animal welfare, expanding market access, and ensuring food safety and quality. Farmers should be trained about alternative feed sources, manure management, biosecurity, and renewable source uses. Another vital aspect is raising consumer and retailer awareness of sustainable poultry products (Rodriguez et al., 2009; Martinez Michel et al., 2011). People hesitate to pay premium prices (Vanhonacker and Verbeke, 2009; Martinez Michel et al., 2011). To encourage them, it is essential to have proper labeling, health, welfare, and environmental benefits. Addressing these knowledge gaps can improve the poultry industry's sustainability and competitiveness. It also contributes to global food security and environmental protection. Government agencies, NGOs, and industry organizations must help to spread information about sustainable practices and their benefits to poultry farmers.
Institutional Support and Policy Framework
Institutional support and policy framework are crucial for adopting and implementing sustainable poultry farming (UNDP, 2023). Advancing sustainable poultry production and processing knowledge and technology relies heavily on research and innovation supported by organizations like the Food and Agriculture Organization (UNDP, 2023). Extension and education programs promoted by organizations like the World Poultry Foundation are pivotal in enhancing the skills and awareness in the poultry supply chain (UNCC, 2023). These efforts promote the transfer of knowledge and technology while encouraging attitudes and behaviors to support sustainability principles. However, extension and education face challenges like resource constraints, limited coverage, and quality issues, necessitating tailored, interactive, inclusive, and continuous improvement efforts.
Higher education institutions are increasingly acknowledged for driving and facilitating sustainability as countries strive to achieve the UN's 2030 Sustainable Development Goals (UNDP, 2023) and meet commitments under the Paris Agreement to reduce greenhouse gas emissions by 43% by 2030 (UNCC, 2023). Many universities and higher educational institutions are now adopting institutional sustainability assessments to evaluate their sustainability performance and monitor their progress in this context (Findler et al., 2019). Inadequate support from government agencies, research institutions, and industry associations can slow the development and dissemination of sustainable technologies, practices, and knowledge. Furthermore, research institutions and agricultural universities can contribute by researching and providing evidence-based guidelines for sustainable poultry production. Establishing clear sustainability standards and certification schemes can also enhance consumer trust and drive demand for sustainable poultry products.
FUTURE DIRECTIONS
Sustainable poultry farming has a promising future, offering opportunities for industry growth, resilience, and environmental stewardship. This section discusses potential opportunities and recommends adopting sustainable poultry farming practices.
Integrated Farming Systems
The future of sustainable poultry farming lies in integrated farming systems. To optimize resources, integrate poultry production with other agricultural systems like crop farming, agroforestry, or aquaculture (Prinsloo et al., 1999; Brown et al., 2018; Georganas et al., 2023). It helps to enhance nutrient cycling and create self-sustaining agricultural ecosystems. Agroecology follows principles by applying ecological and social concepts to promote sustainable agriculture through local breed preservation, organic feed utilization, natural pest control, crop-livestock integration, agroforestry, and participatory research and innovation (Kryger et al., 2010; Westerman, 2017; Brown et al., 2018). It also includes the concept of climate-smart agriculture to help poultry farmers mitigate the effects of climate change, productivity improvement, and emissions reduction (FAO, 2023c). Climate-smart agriculture promotes using alternative energy sources, improving waste management, diversifying products, and sequestering carbon. In addition, integrated organic farming systems encompass agricultural activities like residue recycling, bio-intensive cropping, horticulture, livestock, and poultry farming (Layek et al., 2023; AgriFarming, 2023a; Agricial, 2023). Its benefits poultry farming through cost reduction, improved soil fertility, food quality and safety, and the creation of value-added products. In recent years, large foundation models (e.g., Meta AI SAM and OpenAI ChatGPT), robotics, and cybernetics have achieved breakthroughs and were applied for supporting sustainable poultry production (Yang et al., 2024a, 2024b). How to incorporate those emerging technologies or systems into existing farming operation for promoting animal welfare management and environmental protection deserves further studies. For instance, precision animal welfare management could reduce mortality and improve food safety and waste, which will reduce the environmental footprints of poultry and egg production (Bist et al., 2024a; Yang et al., 2024c; Zhou et al., 2024).
Research and Innovation Roadmap
The world population is projected to be 9.7 billion by 2050 (United Nations, 2019). Feeding an increased population while managing limited land, water, and energy resources by protecting soil fertility presents a significant challenge (Gomiero et al., 2011). A research and innovation roadmap is essential to address this challenge and improve sustainability (UNDP, 2023). Research efforts should address key industry challenges such as disease management, feed efficiency, and waste utilization while exploring new technologies and innovative solutions. Funding agencies, governments, and private sectors must prioritize resources for research projects. Researchers, farmers, and industry stakeholders must collaborate to get scientifically rigorous, practical, repeatable, and scalable research outcomes. One important research and innovation area in sustainable poultry farming involves investigating alternative feed sources. Exploring alternative feed sources holds promise for reducing costs and environmental impacts in poultry production (El-Deek et al., 2020; Kulshreshtha et al., 2020; Sajid et al., 2023). Developing technologies and practices such as biogas, composting, biochar, or fertilizer production can significantly enhance sustainability. Developing technologies and practices to prevent diseases, reduce stress, and improve poultry comfort is crucial for industry productivity and ensuring food safety, quality, and consumer acceptance (UNDP, 2023). These research and innovation endeavors collectively empower the poultry industry to enhance sustainability, competitiveness, global food security, and environmental preservation.
Education and Extension Services
Education and extension services are critical in equipping poultry farmers and stakeholders with the knowledge and skills necessary for sustainability. These services serve as pathways for distributing essential information, delivering technical training, and providing resources (Owoade and Akinwale, 2019). However, they frequently face challenges like resource constraints, insufficient coverage, and service quality issues, highlighting the urgent need for strengthening education and extension services. This involves adapting services to meet the specific needs of poultry farmers, making them interactive and inclusive. It is important to ensure continuous availability to bridge the knowledge gap and provide the latest sustainable poultry farming practices. The future of education and extension services holds promising prospects to enhance the sustainability and competitiveness of the poultry industry. One such service is utilizing online and digital platforms. This online platform offers a convenient, cost-effective, and interactive means of accessing information, training, and communication. Furthermore, participatory and experiential learning approaches are gaining attention by offering hands-on opportunities to engage in practical experiences and develop critical thinking and problem-solving skills. Hands-on experience can be achieved through field visits, demonstrations, workshops, and farmer-to-farmer networks. Continuous evaluation and improvement are crucial to maintain the high quality, relevance, and effectiveness of education and extension services. Monitoring tools like surveys, interviews, focus groups, and performance indicators can assess poultry farmers' and extension agents' satisfaction, knowledge acquisition, behavior change, and overall performance.
CONCLUSIONS
Sustainable poultry farming involves a comprehensive approach prioritizing animal welfare, environmental conservation, and efficient resource use. Integrating alternative feeds, precision technologies, genetics, and biotechnology offers exciting opportunities to enhance sustainability. This approach is essential for minimizing ecological impact, maintaining ethical standards, improving economic viability, building resilience, and promoting social equity. It requires collaborative efforts from governments, research institutions, industry associations, farmers, and consumers. Governments should establish supportive policies and funding mechanisms. Research institutions should emphasize sustainability research, and industry associations should promote ethical and environmentally friendly practices. Farmers contribute significantly by adopting sustainable practices and investing in continuous improvement, while consumers can drive change by supporting ethical products. In conclusion, sustainable poultry farming is the path to a responsible, resilient, and eco-conscious poultry industry, contributing to a more sustainable global community.
DISCLOSURES
The authors declare no conflicts of interest.
ACKNOWLEDGMENTS
The study was sponsored by the USDA-NIFA AFRI (2023-68008-39853), Georgia Research Alliance, and USDA-NIFA Hatch Multistate projects: Fostering Technologies, Metrics, and Behaviors for Sustainable Advances in Animal Agriculture (S1074).
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