What is animal welfare? Common definitions and their practical consequences

Introduction

In concluding my first article, I proposed that “...whatever we decide (about animal welfare) as a profession or as individuals, we must be knowledgeable” (1). In this and succeeding articles, some fundamental points will be covered, starting with what animal welfare is and how definitions affect the way animals are treated.

What is animal welfare?

The term “animal welfare” is being used increasingly by corporations, consumers, veterinarians, politicians, and others. However, the term can mean different things to different people. Understandably, in the past, veterinarians and farmers have seen animal welfare chiefly in terms of the body and the physical environment (shelter, feed, etc.) (2): if an animal is healthy and producing well, it is faring well. Research on aspects of animal welfare has also focused on the body, using physiological measures, such as endorphins, plasma cortisol, and heart rate, to examine how the animal is coping with its environment (3). However, there are limitations to seeing animal welfare only in terms of the body. One limitation is that genetics and the environment can produce desirable physical outcomes, even though the animal's mental state is compromised. For example, a canine breed champion may have perfect conformation and be in perfect health, but it may be very anxious in its home environment. Another limitation is that some physical parameters (heart rate, plasma cortisol) are difficult to interpret, because they can be increased by both positive and negative experiences, such as the presence of a mate and the presence of a predator.

The above would suggest that animal welfare includes not only the state of the animal's body, but also its feelings. Most would agree that animals have feelings (fear, frustration), and it has been proposed that animal welfare consists entirely in feelings and that these have evolved to protect the animal's primary needs (4). Thus, if an animal feels well, it is faring well (4,5). A feelings-based approach to welfare research typically measures behavioral outcomes, such as willingness to “work” (pushing open a weighted door), and behavioral signs of fear or frustration. Such research has led to the conclusion that animals have fundamental behavioral needs that they must be allowed to satisfy for humane reasons (6).

A third view of welfare, linked to the feelings-based approach, is that animals fare best if they can live according to their nature (7,8) and perform their full range of behaviors (8). In this case, physical suffering, such as feeling cold, and mental suffering, such as the fear induced by being preyed upon, may be acceptable. Sectors of the general public favor the “natural living” approach, however, as with physical and mental aspects of welfare, animal welfare scientists have largely discounted this as the sole basis for ensuring optimal welfare. Instead, they propose that the physical, mental, and “natural-living” aspects of welfare are interrelated and are all of ethical concern (9,10). Thus, the most widely accepted definition of animal welfare is that it comprises the state of the animal's body and mind, and the extent to which its nature (genetic traits manifest in breed and temperament) is satisfied (11). However, the 3 aspects of welfare sometimes conflict, and this presents practical and ethical challenges.

From definitions to the real world

The situation of laying hens illustrates how the physical, mental, and natural aspects of welfare can conflict, and the difficulty in agreeing on how best to compromise among them. Disagreement occurs because the form of compromise that is acceptable to different animal-oriented groups depends on their values (10,12) and is complicated by the need to consider legitimate human interests (those of the farmer in earning a living).

In the case of laying hens, noncage systems have been advocated, so that the birds might live more according to their nature and thus avoid the frustration of close confinement in barren cages. However, cannibalism is common in noncage systems, perhaps because hens are not adapted to living in the large groups involved in noncage systems (13). These systems can also carry a greater risk of disease and are more labor intensive than are conventional cages. These difficulties can be managed somewhat (cannibalism can be controlled by beak-trimming, which is itself questionable, because it causes neuromas and chronic pain (14,15)), but conventional cages have been considered more desirable in both financial and humane terms. Veterinarians have accepted this compromise, which is consistent with their focus on animals' physical welfare and with their role in helping farmers to provide affordable food. However, conventional cages do not permit hens to express their nature (roost at night, dust-bathe, lay eggs in seclusion). This limitation has contributed to the view that conventional cages are unacceptable and that hens bear too many of the costs of egg production without sufficient benefit. The European Union (EU) has ruled that barren cages be phased out of all member countries by 2012 and that more space be provided for birds in the interim (13). This ruling represents a new compromise among the physical, mental, and natural aspects of hen welfare. The ruling also involves human compromise in that the potential increase in the production costs under alternative systems is estimated at 5% to 50%, depending on the system used (13), which will increase the cost to consumers. The premise of the ruling is that animal welfare is a public good that society must pay to protect. However, some animal welfare scientists argue that there is insufficient scientific evidence to justify the ruling and that welfare may be worse because of it. Other scientists support the ruling, arguing that it is inadequate husbandry and the current market conditions that can reduce welfare under the housing systems required by the EU ruling. Both sides represent a compromise, the acceptability of which depends not only on scientific evidence, but also on values.

Assessing animal welfare

Turning to North America, the existing compromise between human interests and the 3 aspects of animal welfare is being reconsidered. In the United States, the fast-food restaurant industry now requires higher welfare standards in the farms that supply its eggs, and it assesses compliance with this requirement through third-party welfare audits (16). This action is market-driven and therefore not a sufficient framework for national reforms in animal welfare standards. In Canada, the restaurant industry and others are debating the feasibility of welfare auditing for food animals.

Auditing implies that animal welfare can be assessed in a practical way, but, as we have seen, welfare is complex. The assessment of animal welfare will be examined in the next article.