Table 4.

Growth performance and health of poultry birds fed fruit pomaces as reported in recent literature.

Fruit pomaces	Inclusion levels, %	Poultry species	Effects	References
Apple pomace
Dried apple pomace (DAP)	4, 8, and 12 8, 12, and 16 12, 16, and 20	Broiler chickens	i.Incremental DAP at 4% and 8% improved daily FI and DWG of birds DAP at starter and grower phases, respectively, better than those fed 12% and 16% DAP. ii.Improved gut morphology parameters. iii.Increased antibody titre against Newcastle disease virus (NDV) and sheep red blood cell iv.Increased IgG and IgM titre and total antioxidant capacity.	Aghili et al. (2019)
Apple pomace (AP)	10, 15, and 20	Broiler chickens	A significant depression of weight gain (WG) when 15% and 20% DAP. However, WG was significantly improved following enzyme supplementation.	Matoo et al. (2001)
AP	3 and 6	Broiler chickens	i.No effect was observed for growth performance, gut histomorphometry, and histopathology. ii.Significant increase in the intestinal Short-chain fatty acid concentrations among birds fed fruit pomace diets. iii.In AP-fed birds, beta-diversity was significantly increased while alpha-diversity was unaffected. AP reduced the population of genus Lactobacillus, while the Streptococcaceae family was increased compared to the control treatment.	Colombino et al. (2020)
AP	10 and 20	Broiler chickens	Dietary 20% AP significantly reduced WG and FE. However, at 10%, birds' performance was not affected.	Bhat et al. (2000)
AP ± molasses	15	Broiler chickens	With 10% molasses supplementation into dietary AP, BW, FI, FCR, and survivability of birds were not affected.	Bhat (2004)
AP	5, 10, and 15	Broiler chickens	Increased FI and FCR.	Ayhan et al. (2009)
AP	5	Turkey	On the overall, AP maintained growth performance and carcass characteristics of turkey.	Juskiewicz et al. (2015)
AP	5	Turkey Poult	i.Maintained BW of birds. ii.Increased small intestine weight. iii.Increased maltase and sucrase activities in the small intestine. iv.Improved bacterial enzymes in the caecal digesta. v.Increased butyric, valeric and total putrefactive SCFA in the caecum.	Juskiewicz et al. (2016)
Olive pomace/by-products
Olive pulp ± xylanase (enzyme)	9	Laying hens	i.Feed intake and EM were similar across the treatments. ii.Improved FCR among birds fed olive pulp treated with xylanase. No report on gut health.	Zarei et al. (2011)
Olive pulp ± yeasture (probiotic)	16	Laying hens	i.Dietary olive pulp at the inclusion level yielded a similar FI, % HDP, and EM, and a significantly increased FCR. ii.Probiotic supplementations into all the dietary treatments significantly reduce haugh unit and %HDP. iii.No significant interaction between olive pulp and probiotic supplementation. No report on gut health.	Afsari et al. (2013)
Olive pomace	10	Laying hens	i.Feed intake and FCR were maintained. ii.Reduced egg cholesterol content by downregulating five genes responsible for cholesterol biosynthesis. No report on gut health.	Iannaccone et al. (2019)
Olive pulp ± hemicell (enzyme)	4.5 and 9	Laying hens	i.Non-significant improvement in the overall egg mass and FCR fed 4.5% olive pulp with or without enzyme supplementation. ii.A significant interaction effect of olive pulp and enzyme which increases egg weight when β-mannanase was included in the 9% olive pulp diet. iii.Diet containing 4.5% olive pulp increases antibody response against NDV. iv.Blood Serum hormones and metabolites were not affected by dietary olive pulp. No report on gut health	Zangeneh and Torki (2011)
Olive pulp	2.5 and 5 5 and 8	Male broiler chickens	i.Regardless of the inclusion level of olive pulp, FI, BW gain, and FCR of birds were not affected during the grower and finisher phase. ii.In addition, the proportion of total PUFA was not affected.	Papadomichelakis et al. (2019)
Olive pulp	2.5 and 5 5 and 8	Broiler chickens	i.Overall FI and BW gain were not affected; however, FCR was significantly reduced among birds fed 8% olive pulp. ii.Mortality was reportedly similar across the treatment; however, it was zero when 5 and 8% olive pulp was fed. iii.No difference in the plasma SOD, CAT, GST, and GPx. No report on gut health.	Pappas et al. (2019)
Olive pomace	2.5, 5, and 7.5	Broiler chickens	Increased growth rate and reduced FCR were achieved when birds were fed 5% and 7.5%. No report on gut health.	Nasopoulou et al. (2018)
Olive cake ± yeast	5 and 10	Broiler chickens	i.Similar FI, FCR, and EPEI were reported regardless of dietary olive cake and/or yeast supplementation inclusion levels. ii.Relative weight of spleen and bursa was similar across the treatments. iii.Olive cake diet at 5% and 10% without yeast supplementation reduces total plasma lipid, increases plasma TAG and cholesterol, HDL:LDL, and VLDL. No report on gut health.	Al-Harthi (2016)
Olive cake	5, 10, and 20	Broiler chickens	i.The best BW and FCR were achieved at 5% and 10% olive cake supplementation. ii.Decreased abdominal fat among birds fed olive cake. iii.Significant reduction in total plasma cholesterol in all birds fed olive cake. iv.Significant increase in breast muscle vitamin E and reduction in liver MDA in birds fed olive cake. No report on gut health.	Saleh and Alzawqari (2021)
Olive pulp ± multi-enzyme ± processing (destoning)	5 and 10	Broiler chickens	i.No difference in FI, WG, FE among birds fed 5% and 10% olive pulp. Enzyme supplementation also makes no difference in the growth performance parameters. ii.In addition, the destoning processing method yielded a significantly reduced WG and increased feed efficiency. iii.Feed cost was significantly lower in the 5% olive pulp diet compared to 10%. Processing and enzyme supplementation did not affect feed cost; however, they produced a significant interaction effect.	Sayehban et al. (2016)
Olive cake ± citric acid	10 and 20	Broiler chickens	i.Feed intake and BW of birds fed 10% Olive cake or control with no citric acid, respectively, were better compared to the FI and BW obtained at 20% olive cake with or without citric acid. ii.RBC was significantly reduced in birds fed 20% Olive cake which increased following citric acid supplementation. However, in the 10% Olive cake treatment, RBC, PCV, haemoglobin, MCV, and MCH were favourably compared to control with or with citric acid. iii.Liver ratio was significantly reduced compared to the 20% olive cake and control treatments.	Al-Harthi and Attia (2016)
Olive pulp ± multi-enzyme ± processing (destoning)	5 and 10	Broiler chickens	Despite the processing method and enzyme supplementation, carcass and offal traits of broiler chickens were not affected by olive pulp supplementation.	Sayehban et al. (2020)
Olive pulp	5, 10, and 15	Broiler chickens	i.Significantly reduced BW and FCR among birds fed 10% and 15% olive pulp. However, the reduction might be due to the significantly reduced abdominal fat in birds fed 10% and 15% olive pulp. ii.A significant linear increase in the percentage of gizzard as olive pulp inclusion increases. iii.Unlike other immune organs, the percentage of the thymus was significantly increased with increasing inclusion levels of olive pulp.	Elbaz et al. (2020)
Olive pulp ± irradiation	5 and 10	Quail	i.Live BW was significantly increased in all the olive pulp treatments with or without irradiation. However, WG was non-significantly improved in all olive pulp treatments. ii.Dietary olive pulp significantly increased WBC, Hb, MCH, MCHC, and AST.	El-Hady et al. (2018)
olive pulp ± irradiation	3 and 6	Quail	i.Egg production, EW, FE, fertility, embryonic mortality, hatching percentage, and weight of chicks at hatch were significantly improved at both 3% and 6% irradiated olive pulp (IOP); however, it was highest at the latter. ii.Significant improvement in RBC and PCV in all diets containing olive pulp regardless of processing. However, WBC and Hb were significantly higher in the IOP treatments. iii.Intestinal length was also highest in the IOP treatments.	Ibrahim et al. (2019)
Grape pomace
Red grape pomace (RGP)	2.5	Broiler chickens	i.Birds' FI was higher when 2.5% RGP was fed and was compared favourably to antibiotic-treated birds. Reduced BW was observed in RGP-birds during the grower phase; however, overall FCR was similar compared to antibiotics. ii.Significant improvement in gut histomorphometric on the RGP-fed birds and was better compared to antibiotic treatments. iii.Significantly decreases Firmicute to Bacteroidetes ratio and improves the population of beneficial microbes, including Lactobacillus spp.	Erinle et al. (2021)
RGP	1.5, 3, 4.5, and 6	Cockerels (chickens)	i.The increasing dietary RGP did not affect the overall FI, body WG, FCR and slaughtered weight of cockerels. ii.MCH and GLB increase significantly with increasing inclusion levels of RGP.	Jonathan et al. (2021)
Grape pomace (GP)	450, 350, and 250 mg/kg	Broiler chickens	i.Similar BW was reported across the dietary treatments. ii.There was a significant reduction in LDL of birds at 450 mg/kg inclusion of GP. iii.Increased SOD at the highest dose of GP while GPx was not affected.	Dupak et al. (2021)
GP ± fermentation	1.5	Broiler chickens	i.Fermented GP (FGP) improves final BW in the same capacity as the synthetic antioxidant treatment; however, it was better when compared to raw GP. ii.Raw GP at 1.5% significantly increased serum GPx and SOD, while CAT was increased when 1.5% FGP was fed. iii.FGP significantly decimates Clostridium perfringens population compared to other treatments; however, other bacterial species, including Lactobacillus were not affected. iv.Regardless of fermentation, the GP treatments significantly reduce VH and VH:CD.	Gungor et al. (2021)
GP	7.5 and 15	Broiler chickens	i.Dietary GP significantly lower FI and FCR and higher BW and was compared favourably to birds fed vitamin C and E, respectively. ii.Dietary GP significantly lower AST, ALT, and TAG and higher TP, GLB, HDL; however, it was similar to the vitamin C, and E-fed birds. Additionally, 15% GP reduces TC and LDL compared to other treatments. iii.Dietary GP significantly increases IgG, IgM, IgA, and SOD, and lower MDA and were comparable to vitamins C and E.	Mankola et al. (2021)
GP ± enzyme complex ± tannase	5 and 10	Broiler chickens	i.Dietary 5% GP significantly increases protein and total polyphenol digestibilities. However, supplementation of enzyme complex or tannase or a combination of both reduces the 2 digestibilities. ii.Significant increase in the plasma α-tocopherol and antioxidant capacity of birds fed 5% GP and vitamin E, respectively.	Chamorro et al. (2017)
RGP	2.5, 4.5, 5.5, and 7.5	Broiler chickens	i.Average weekly FI and FCR significantly reduced when 7.5% RGP was fed compared to other RGP levels and control. However, overall WG was not affected. ii.Blood parameters and carcass characteristics were not affected.	Kumanda et al. (2019)
GP	5, 7.5, and 10	Broiler chickens	i.No difference in the performance of birds by the increasing inclusion levels of GP. ii.Blood antioxidants, SOD and GPx, were significantly higher while MDA was reduced among 5 and 7.5% GP-fed birds. iii.All inclusion levels of GP reduced serum TAG and LDL while HDL was increased. iv.Significantly increased antibody titre against NDV among birds fed 5% and 10% GP.	Ebrahimzadeh et al. (2018)
RGP	5, 10, and 20	Broiler chickens	i.Increasing levels of GP increase FI particularly at the starter and grower phase; however, BW gain and FCR were not affected. ii.Increasing levels of GP reduce abdominal fat in heat-stressed birds. iii.Increasing levels of GP reduce plasma cholesterol, LDL, AST, MDA, and TAG while HDL, TP, GPx, and SOD were increased. iv.GP increases weights of immune organs, bursa and thymus.	Hosseini-Vashan et al. (2020)
RGP and white grape pomace (WGP)	20 RGP and 20 WGP	Broiler chickens	i.Dietary WGP did not affect BW, daily WG, FI and FCR, while RGP increased overall FCR. ii.Dietary WGP increases the antioxidant capacity of breast and leg meat compared to the RGP and control treatments.	Reyes et al. (2020)
GP	1, 2, 3, and 4	Laying hens	i.Dietary GP at 3% and 4% improved FCR, %EP, EM, SOD, and GPx compared to control treatment. ii.The %EP, EN, and EM were significantly higher among 4% GP-fed birds compared to those fed Vitamin E.	Alm El-Dein et al. (2017)
RGP	1.5, 3.5, and 5.5	Quail	i.Overall, FI was significantly improved at 3.5% RGP compared to other treatments. However, overall BW gain, FCE, and final BW were not influenced by the varying inclusion level of RGP. ii.Similarly, the serum biochemical parameters of the birds were not affected.	Mnisi et al. (2021)
Strawberry pomace
Strawberry pomace (SP) and/or Seedless strawberry pomace	5	Turkey	i.On overall, SP, seedless SP, and a combination of both maintained turkey's growth performance and carcass characteristics.	Juskiewicz et al. (2015)
SP	3 and 6%	Broiler chickens	i.No effect was observed for growth performance, gut histomorphometry, histopathology. ii.Significant increase in the intestinal SCFA concentrations among birds fed fruit pomace diets including SP. iii.In SP-fed birds, beta-diversity was significantly increased while alpha-diversity was unaffected. SP reduced the population of genus Lactobacillus compared to the non-fruit pomace treatment.	Colombino et al. (2020)
SP	5	Turkey Poult	i.Maintained BW of birds. ii.Decreased small intestine weight. iii.Reduced maltase and sucrase activities in the small intestine. iv.Improved bacterial enzymes in the caecal digesta. v.Increased butyric acid in the caecum.	Juskiewicz et al. (2016)
Seedless strawberry pomace (SSP)	5	Turkey Poult	i.Maintained BW of birds. ii.Decreased small intestine weight and increased digesta viscosity. iii.Reduced maltase and sucrase activities in the small intestine. iv.Improved bacterial enzymes in the caecal digesta. v.Increased butyric and propionic acids in the caecum	Juskiewicz et al. (2016)
SSP	5	Turkey	i.TBARS concentration in raw and frozen breast muscle of turkey fed 5% SSP was drastically reduced compared to some other fruit pomaces. ii.Similarly, vitamin E levels were highest in raw breast meat of Turkey.	Juskiewicz et al. (2017)
Blueberry pomace
Blueberry extract (BE)	0.5, 1, and 2	Broiler chickens	i.Significantly increased BW gain and reduced FI and FCR as BE inclusion levels increases. ii.Significantly increased slaughter weight and dressing and gizzard percentage among BE-fed birds compared to control.	Ölmez et al. (2021)
Blueberry pomace	1 and 2	Broiler chickens	i.Decreased TAG and ALT. ii.Reduced prevalence of necrotic enteritis when 1% blueberry pomace was fed.	Das et al. (2020)
Cranberry pomace
Cranberry pomace	1 and 2	Broiler chickens	i.Increased serum IgG among birds bed 2% cranberry pomace. ii.Both levels of cranberry pomace resulted in improved innate immune and suppressed proinflammatory cytokine.	Das et al. (2021)
cranberry pomace extract	0.1, 0.2, and 0.4	Broiler chickens	i.Improved immunity caused by increased IgM concentration. ii.Antibody titres against infectious bursa disease virus increase as the cranberry pomace extract increases.	Islam et al. (2017)
cranberry pomace	1 and 2	Broiler chickens	i.Decreased TAG and ALT. ii.Increased the relative abundance of Lactobacillaceae in the caecal of birds fed 2% cranberry pomace. iii.Upregulation of adaptive immune related genes. iv.Similar to antibiotic effect, 1% cranberry pomace reduced prevalence of necrotic enteritis v.Improved BW in the same capacity of Bacitracin-fed birds.	Das et al. (2020)
cranberry pomace	1 and 2	Broiler chickens	i.Improved blood serum iron while cholesterol was reduced. ii.Selective modulation of gut microbe by improving beneficial, SCFA-producing gut bacteria while reducing the pathogenic ones.	Islam et al. (2020)

± = with or without; ALT = alanine transaminase; AST = aspartate transaminase; BW = body weight; CAT = catalase; DWG = daily weight gain; EM = egg mass; EW = egg weight; EN = egg number; %EP = percentage egg production; EPEI = European production efficiency index; FCR = feed conversion ratio; FCE = feed conversion efficiency; FE = feed efficiency; FI = feed intake; GLB = globulin; GST = glutathione transferase; GPx = glutathione peroxidase; HDL = high density lipoprotein; %HDP = percentage hen-day production; IgM = immunoglobin M; IgG = immunoglobin G; IgA = immunoglobin A; LDL = low density lipoprotein; MCHC = mean corpuscular hemoglobin concentration; MCV = mean corpuscular volume; MCH = mean corpuscular haemoglobin; MDA = malondialdehyde; PCV = packed cell volume; PUFA = polyunsaturated fatty acids; RBC = red blood cell; SOD = superoxide dismutase; TAG = triglycerides; TBARS = thiobarbituric acid reactive substances; TC = total cholesterol; TP = total protein; VLDL = very low density lipoprotein; WG = weight gain.