Animal Welfare
• One component of meat quality recognized by many people is ethical quality. This has two main elements. One is producing meat in
agricultural systems that are sustainable and environmentally friendly, the other is producing it in ways sympathetic to animal welfare.
• Different individuals have widely varying views of the importance of these concepts. This is especially true of animal welfare where our viewpoint largely reflects how we see animals in relation to ourselves.
• It is therefore an emotive subject. Those who have greatest empathy with animals are most concerned about their welfare.
Defining animal welfare
• Welfare is hard to define precisely. It obviously
relates to an animal’s mental and physical well-being.
• Physical well-being implies that an animal is fit and healthy, but mental well-being is harder to define because it is difficult to know whether an animal is content or not with its environment. This implies that just because an animal is healthy does not mean that its welfare is necessarily good. Neither does
productivity, for example fast growth or high milk production, aloneimply good welfare.
• The implication is that welfare is compromised if an animal cannot cope with its environment or can only cope with difficulty. In this sense the environment means anything outside the animal, whether the physical environment or, for example, other animals.
• This concept of welfare leads to the recognition of two types of welfare indicator. The first type is one that shows that an animal has failed to cope with its environment. Examples are increased mortality, reduced reproductive capacity, greater disease and reduced growth.
• The second type shows the amount of effort required to cope.
Examples of this type are indices of distress or stress, such as increased heart rate, and behavioural changes. The welfare of a man being chased by a lion is likely to be low. If the lion catches and eats the man, the
man has failed to cope with his environment. The man’s death is an indicator of the first type. If the lion doesn’t quite succeed in catching the man then, although the man survives, he is still likely to be very distressed by the experience and we could assess this by his behaviour and probably by noting the rise in his heart rate. These are examples of the second type of welfare indicator.
Types of welfare concern in meat animals
• The various concerns that people have about the welfare of meat animals can be considered under several headings. Some relate to breeding, some to rearing conditions, some to management practices during rearing and some to potential fear and pain at slaughter.
• Obviously they have different time scales and this may be important in helping to decide how serious a concern they are to us.
• Things that are of greatest concern operate over a long time or are severe. To a degree, a third factor, the number of individuals affected, seems
intuitively important. Something that affects large numbers of animals appears to be more important than something that affects only a few. However, welfare must really be considered at the level of the individual. A system that fails even a few
individuals is unacceptable from a welfare point of view.
Stress
The concept of stress
• We have seen that an animal’s welfare is compromised where it cannot
• cope with its ‘environment’ or can only cope with difficulty. The
• environment effect is often referred to as a ‘stress’ or ‘stressor’. A stress
• may overtax the animal’s ability to cope and reduce its ‘fitness’. In this
• sense fitness means lack of disease, injury, death or ability to reproduce.
• An animal normally responds to stress with physiological and
• behavioural changes that are designed to be adaptive or to promote
• survival. In our example of the man chased by the lion, the behavioural
• response was running away, and the probable increase in his heart rate
• a physiological response to improve the flow of oxygenated blood to
• his muscles to facilitate the running.
• Rather confusingly, the words
• ‘stress’ and ‘stressor’ are used to mean either the same thing, or
• different things, by different people. Where they are used to mean
• different things, ‘stressor’ refers to the environmental pressure or stimulus, and ‘stress’ is reserved for the animal’s response to it. In the
• second sense we talk of an animal being in a stressed state as well as
• referring to the stimulus as a stress.
The nature of the stress response
• Animals respond physiologically to stresses in a characteristic way. This stress response has two components. The first is a rapid shortterm ‘alarm’
response.
• The animal’s response to a threat, for example the
sudden arrival of a predator, is to prepare its body for
‘flight or fight’. The preparations largely involve the activity of the sympatho-adrenal system and the
secretion of the catecholamine hormones, adrenaline and noradrenaline (epinephrine and
norepinephrine).
• The second component of the stress response occurs after the
‘alarm’ response and over a longer time period. Its role is to allow the animal to recover from the alarm
response or to ‘adapt’ to the new situation. It was first recognized by Hans Selye working in the 1950s who referred to it as the General Adaptation Syndrome
when considered along with the alarm response. This component of the animal’s response to stress mainly involves the hypophyseal-adrenal axis.
Pain
Pain is a special kind of stress. It is not easy to define concisely. The International Society for the Study of Pain defines it as: ‘Pain is an unpleasant sensory and emotional experience associated with actual or
potential tissue damage or described in terms of such damage’. The key
points are that it is aversive, and that in general it is associated with tissue damage. Bruises and broken bones have already been
described
as examples of likely painful experiences. Because pain is a subjective perception it is very hard to measure objectively.
• Most animals in pain show a stress response but this is not specific.
• They usually exhibit behavioural changes, particularly in posture and gait.
• They may rest in a hunched-up posture. Animals that have injured feet or legs Show obvious signs of lameness. Animals in pain may vocalize. A particularly powerful tool in
investigating whether animals are in pain is to observe
changes in their behaviour after administration of analgesics.
• A return to ‘normal’ behaviour implies that the animals were previously in pain.
