- Email: [email protected]
Management of pain in production animals
Applied Animal Behaviour Science 59 Ž1998. 147–156
Management of pain in production animals G.F. Bath
)
Section Herd Health and Production, Faculty of Veterinary Science, UniÕersity of Pretoria, PriÕate Bag X04, Onderstepoort 0110, Pretoria, South Africa
Abstract The measurement and evaluation of animal welfare and pain is difficult and ultimately subjective. However, we are ethically bound to make our best assessment and reduce suffering. Evaluation can be made on the basis of chemical changes, behaviour, performance or extrapolation, and preferably a combination of these. Since pain in production animals cannot be totally eliminated, it has to be minimised by management, which must take into account the profitability and practicality of proposed actions and address all forms of pain and distress. This implies that behavioural, feeding, management and breeding aspects should also receive attention. Acts as well as omissions have to be assessed. Considerations in assessing actions or omissions include intention, alternatives, predictability, control measures, awareness, expertise, socio-economic situation and necessity. To control pain in production animals we must know the following: Ža. what is meant by pain and how it arises, Žb. the farming system, Žc. the animal and its needs, Žd. interventions, Že. alternatives available, Žf. production implications of advice, Žg. how to motivate farmers, Žh. how to arrange proper training, Ži. setting of minimum requirements, and Žj. monitoring of performance. Farmer support is essential for success. This should be achieved by persuasion arising from awareness—a positive interaction between specialists, veterinarians, farmers and staff is needed. Legal requirements and prohibitions should be a backup and not the central driving force. Minimising pain arising from any farm operation or procedure requires that the following are in place: Ža. it is done for the right reasons, Žb. it is done by the best method, Žc. the correct equipment is used, Žd. it is done at the right time, Že. it is done to the right class of animal, Žf. correct follow-up is carried out, and Žg. the persons are properly trained. The best way to entrench these principles is to make it a legal and ethical requirement that only persons who have the required knowledge, skill and equipment should be allowed to undertake farm operations and procedures. q 1998 Elsevier Science B.V. All rights reserved. Keywords: Animal welfare; Pain; Production animals; Management; Evaluation
)
Fax: q27-12-529-8315; e-mail: [email protected]
0168-1591r98r$19.00 q 1998 Elsevier Science B.V. All rights reserved. PII S 0 1 6 8 - 1 5 9 1 Ž 9 8 . 0 0 1 2 9 - 4
148
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
1. Introduction Every type of interaction between humans and animals is potentially subject to abuse, thus animal welfare has to address a wide field at many levels. It is the breadth and complexity of these interactions which leads to difficulties. In production animals, further complications include the underlying assumption that this interaction has to be to the net benefit of humans. Acceptable production and profit has to be maintained while measures to protect the animals are instituted. There are differences between species, breeds, individuals and production systems which must be taken into account. This contribution is written from the perspective of veterinarians in production animal practice, who must not only safeguard the welfare of animals but also that of their clients. Ž1. One of the chief problems inherent in evaluation of animal welfare or pain is that these are, to a large degree, perceptual and philosophical concepts ŽFrazer, 1993; Rollin, 1993; Rowan, 1993. which are not amenable to measurement in an accurate or objective way. Our attitudes to animal welfare are the result of a complex set of philosophical, religious, cultural, historical and socio-economic factors, as well as objective current scientific evaluation or measurement ŽMcFarland, 1985.. Ž2. A further difficulty lies in the many terms which are used, often interchangeably, in some contexts while in others they are taken to mean quite different things ŽEwbank, 1988; Gibson, 1988; McFarland, 1985; Ryder, 1983.. What is understood by a given term by one group of people can mean something quite different to others. This is certainly not simply a matter of semantics for fusty lexicographers. Without clarity of meaning there can be no clarity of purpose or a meaningful exchange of ideas. Words such as pain, suffering, discomfort, health, well-being, harmony and normality can mean whatever we choose unless there are certain specific meanings ascribed to them—at least within the context of animal welfare. Ž3. Finally, interconnected with the problem of terminology, we have the problem that there are many forms or types of pain, suffering and discomfort which must be properly recognised, differentiated and defined to make a rational and defensible approach to the management of pain possible ŽEwbank, 1988; Frazer, 1993; Rowan, 1993.. Thus, the problems which arise from our philosophy and our perception of pain and of animal welfare are intertwined with problems associated with the terminology we use and the types of pain which we identify or distinguish. While the ‘five freedoms’ ŽGonyou, 1994. ascribed to animals in many countries is a possible yardstick by which we may measure our progress, or a laudable idea to which we aspire, it needs to be remembered that for the vast majority of countries and peoples in the world, such ‘freedoms’ cannot even be guaranteed to people, let alone animals. Some form of pain in all living creatures is virtually unavoidable. We have to seek ways of minimising unavoidable pain and eliminating avoidable pain. In the final analysis we cannot really be certain of what animals feel and want. We have to avoid arrogant assumptions that we know what animals feel and need and rather adopt a more humble attitude of being custodians of the reasonable requirements of animals in our care. This does not mean we should not try to reduce suffering whenever and however we can. We
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
149
have to use the best current assessment of the status of animal welfare within the context of the situation in which it arises, even though we concede that our assessment remains party subjective. Our approach must be that whenever there is reasonable doubt, the benefit of the doubt should be in favour of the animal.
2. Evaluation If it is accepted that pain in its broadest sense is a perceptual concept arising from a complex interaction of factors then it follows that we must accept that it cannot be measured in the usual ways which scientists prefer. It is not the purpose of this contribution to review the current understanding of pain, but we do have to bear in mind that those measurable physiological, pathological and chemical processes which are described are only the underlying events which give rise to the perception of subjective feelings we call pain. The quality of subjective feelings is dependent on the level of consciousness and awareness of the animal, its psychology arising from its mental processes and emotions. An initial lesion has to lead to subjective feelings to qualify as pain. Further consequences of these feelings are memory, fear, association, anticipation, avoidance, distress and discomfort. 2.1. Causes There are different ways in which pain, distress and discomfort can arise in animals. These can be summarised as follows. Ž1. Physical. This is mainly the result of handling, farm operations and procedures, and results in physical pathologic changes. Ž2. Management. These are the problems which may be inherent in the housing, transportation and production methods in use. Ž3. Inherent behaviour needs. This group of factors may result in distress if it clashes with current management systems. Ž4. Feeding. Apart from the obvious component of undernutrition Žhunger, thirst., we must also consider overnutrition and imbalances. Ž5. Breeding. Only the genetic aspect is considered here. Genetic manipulation can result in severe though usually unintended side effects on animal welfare. Ž6. Chemical. A new but increasing area of concern is the effect of production-enhancing drugs or metabolic regulators on animal welfare. 2.2. Ranking More important perhaps is the need to rank the areas of animal welfare concerns in order of their degree of unacceptability. This hierarchy of reprehensibility is necessary if we are to make progress in some order of priority. A descending list of categories could be as follows. Ž1. Sadism Žcruelty.. Wilfully inflicting physical Žmutilations. or mental pain on animals with malicious intent, for the pleasure this gives to the person who inflicts it.
150
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
This is against the cultural norm and is done with the knowledge that it inflicts pain and suffering. Ž2. Abuse. The deliberate and wanton inflicting of pain usually involving fury or loss of control and excessive or undue action. This does not necessarily include malicious intent for the pleasure derived but is against the cultural norms and level of knowledge of the perpetrator. Ž3. Neglect. Pain or distress caused by lack of compassion, foresight, reasonable care and lack of responsibility. Although the person responsible does nothing active to cause pain or distress, his or her blameworthiness arises from the fact that the results of the omission are severe and could reasonably have been foreseen by a compassionate person. These actions are against the norms of that society. Ž4. Deprivation. This differs from the previous category in that the omission is essentially of something unknown or obscure to the person. The norms of the society and its level of knowledge may not automatically assume that omission could be harmful to the animal. Ž5. Ignorance. Acts of commission which are performed due to a lack of awareness or education, but usually within the norms of that society. Ž6. Cultural. Actions arising directly from a societal belief system which is deeply ingrained and thus completely acceptable to that community even though it may be reprehensible to others. Ignorance of the consequences or alternatives is often concomitant. Ž7. Necessity. Actions which involve unavoidable pain, but which are done for reasons which are clearly for the good of the animal or are unavoidable under the circumstances and are performed in the best way available ŽFrench et al., 1994.. Ž8. Good intent. The unforeseen consequences of actions, or the side effects resulting from actions intended to benefit the animal. 2.3. Measurement Measurement or assessment of pain has been attempted in several ways, each with their advantages and disadvantages. Ž1. Chemical. Indicators such as cortisol, endorphins, and lymphokines have been used or advocated ŽMellor and Murray, 1989; Shutt et al., 1987.. The problem is that changes in concentrations may result from many causes and they do not measure the perception of pain as such. They do help to underpin our assessment in an objective way. Ž2. Physiological. Blood pressure, heart rate and immunological measurements are similarly not necessarily or solely related to poor animal welfare, but may be used as research tools ŽOppenheim and Shevach, 1990; Vincent et al., 1993.. Ž3. Pathological. Measurement of lesions, disease incidence or organ changes suffer from the same problems as the previous two categories but may be useful in surveys and research ŽAdams, 1988; Gibson, 1988.. Ž4. Production. The recording of meat, milk, fibre or reproductive performance is of value in that good production cannot occur in the face of very poor welfare, but
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
151
sub-optimal welfare may not be reflected in lower production figures ŽGibson, 1988; Lynch and Alexander, 1977.. Ž5. Performance. The same may be said of performance in those animals which are measured in this way. Ž6. Behavioural. Well-researched ethograms Žnormal behavioural repertoire. are essential for this to be meaningful and do give a more objective measurement, even though indirect, of the perception of the animal ŽGonyou, 1994.. Ž7. Extrapolation. This clearly has many dangers, especially when extrapolation is made between very different families or genera. However, some degree of extrapolation is needed to improve our understanding of perceptions. Ž8. Contextual. Similarly, the basic viewpoint of the observer cannot be totally separated from the observations made. Each evaluation is made subject to the underlying culture, religion or philosophy of the individual and unless we acknowledge this, we fall into the error of according the assessment an objectivity which it lacks. Ž9. Combination. It should be clear that a combination of these ways of assessment is superior to any on its own, and we should try to combine assessments whenever possible. Ultimately we must concede that welfare evaluation is not a tangible measurement but a value judgement ŽBarnett, 1988.. 2.4. Considerations What then are the factors which we need to consider in assessing the acceptability or otherwise of actions or omissions which can affect animal welfare? These can be summarised as follows. Ž1. Intention of actions. Actions intended to hurt must obviously be viewed differently to those intended to help, improve production or performance, or looks, or where the result arises from no specific intention at all. Ž2. Alternatives available. If an action can be avoided by replacement and provided the alternative is both practical and cost effective, then this must be considered an important factor in determining acceptability. Ž3. Predictability of result. In some cases, an unacceptable outcome of a procedure is too unpredictable to be considered a necessary consequence and can therefore not be regarded as an automatic risk. Ž4. Control measures enforced. Often a particular operation can only be evaluated in the context of measures used, or available, to control its potentially unacceptable consequences. Ž5. Awareness of implications. It is only where people are fully aware of the direct and indirect results of their actions that they can be held fully responsible. Knowledge is implicit in blameworthiness. Ž6. Socio-economic levels. The actions or omissions of people living at or below a subsistence level, often with a poor education, must be viewed differently to those of people who are adequately educated and have a reasonable income. Animal welfare cannot be expected to be the top priority of people who are themselves starving. Ž7. Necessity of action. Under given circumstances an action or omission may be unavoidable, even if it does not contribute to animal welfare. It is unrealistic to expect
152
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
farmers to keep stock in optimal condition when droughts occur if this leads to financial disaster. Ž8. Expertise. Before taking on any aspect of animal care, it should be expected that persons are properly trained to do the work in the most humane way practical.
3. Management To control pain in production animals in an effective and reasonable way, we must gain the support of farmers who are responsible for animal welfare on a day to day basis. Winning their support is dependent on winning their confidence that what is proposed is reasonable, justified, practical and profitable. Those who wish to make real progress with controlling pain therefore need a very wide spectrum of knowledge to make good quality animal welfare a reality on farms. 3.1. Knowledge required Ž1. What is meant by terms like pain and distress, and how these arise from physical or management factors. Without a clear understanding of the types of pain and their causes, no defensible evaluation is possible. Ž2. The farming system and its day to day operation. No support will be forthcoming from farmers if proposals for animal welfare are hopelessly at odds with practical or financial realities. We must know the system’s goals, methods and measurements. Ž3. The farm animals and their needs have to be known on the basis of objectively measured ethograms as well as human-derived philosophical values ŽVizard, 1994.. Ž4. Farm operations, procedures and interventions used in practice have to be known as well as the reasons for their use. As can be seen in Tables 1 and 2, the list of interventions can be quite formidable, and some are far more acceptable than others ŽButtle et al., 1986; Hargreaves and Hutson, 1990.. Ž5. Alternative approaches or techniques must be known as well as their advantages and disadvantages, to properly weigh up their application in a given situation. Ž6. Implications of advice on animal production and profitability should be properly understood and evaluated in order to stand a chance of acceptance by farmers. Ž7. Persuading farmers of the moral rightness as well as the financial justification of procedures which are intended to promote animal welfare is crucial to long term improvement in the treatment of animals. This aspect will be further dealt with in Section 3.2. Ž8. Proper training of operators is essential to minimise pain and distress in animals. They must use not only the correct methods, but must apply them correctly and under the right conditions ŽFrench et al., 1994; Vizard, 1994.. Ž9. Minimum requirements or standards for each procedure or operation have to be set and made known. These standards have to be attainable under the practical conditions of the farming system.
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
153
Table 1 Potentially painful procedures performed in production animals by lay persons Procedure
Cattle
Sheeprgoats
Pigs
Electro-immobilisation Electric prodders Ear tags Ear notching Nose rings Branding Tattooing Dehorning Castration Hoof trimming Teeth cutting Mules operation Pizzle dropping Tail docking Teat amputation Shearing Artificial insemination Semen collection Milking Preputial flushing Dystocia relief Dipping Drenching Injection Ži.m. and s.c..
6 6 6 6 6 6 ? 6 6 6 x x x 6 6 x 6 6 6 6 6 6 6 6
6 6 6 6 x x 6 6 6 6 6 6 6 6 6 6 6 6 6 x 6 6 6 6
6 6 6 6 x x 6 x 6 6 6 x x 6 x x 6 6 x 6 6 6 6 6
Table 2 Consequences of poor techniques on animal welfare Sheep
Unfavourable consequences
Procedure
Short term
Long term
Ear tags Ear marks Dehorning Dipping Drenching Vaccination Castration Hoof trimming Teeth grinding Electro-ejaculation Milking AI Sponging Shearing Mules Tail docking Pizzle dropping Dystocia
Pain, bleeding Pain, bleeding Pain, bleeding Pain Pain Pain Pain, haemorrhage Pain, bleeding Pain Pain Pain Pain Tearing, bleeding Pain Pain Pain, bleeding Pain Pain, death
Crumpling, infections Neoplasia Blowfly, infection, scurs Cold, pneumonia, toxicity Pneumonia, abscesses Infection Tetanus, blowfly, infection, evisceration Joint infection Infection Fear Mastitis Infectionrperitonitis Infection, retention Clostridial infections and abscesses, blowfly Blowfly, skewing Tetanus, neoplasia, blowfly, rectal prolapse Ulcers Infection
154
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
Ž10. No system of laws will be of much use if its implementation is not effectively monitored. Thus, a practical monitoring system must be in place together with a programme for taking corrective action if necessary. 3.2. ConÕincing farmers Central to the success of a programme to improve the welfare of animals on a sustained basis is to change the attitudes of farmers. If they can be persuaded that measures to ensure animal welfare are morally justified as well as practical and economically defensible, we will have the best possible safeguard for animals. No law can be of much effect if it is not supported by the great majority of citizens. All too often, the emphasis in animal welfare is placed on legislation, restriction and punishment, rather than persuasion. Yet it is only by convincing those in charge of animals on a daily basis that a real and permanent change can be effected. If most farmers believe in the correctness of welfare safeguards, then these measures will become part of the ethos or culture of that community. Such a commonly held value system is a much more powerful motivator than the fear of prosecution. This does not mean that legislation and enforcement are unnecessary. Unfortunately there will always be a minority who will not respond to anything other than coercion and the threat of punishment. Laws are made for them. Persuasion must begin with awareness. We can expect the correct action from farmers only when they are aware that a given procedure may be unnecessary, or that there are better methods, or that it is unnecessarily painful. It is from this basis, which is where the practising veterinarian can play a pivotal role, that the farmer will be motivated by internal conviction to do things correctly. Specialist researchers have a role to play in laying the objective criteria on which farmer attitudes can be formed. It is through a sustained campaign directed toward farmers via meetings, publications, and especially the farmers’ own organisations that farmers can be convinced that our standpoint is justified. In countries where farmers make use of hired staff to assist with operations, these people must also be properly trained and motivated to improve conditions for animals. 3.3. Requirements for minimising pain We can assume that once we have eliminated all those aspects or practices of animal production which are not essentially part of the production system, we are left with the problem of minimising pain and suffering arising from those practices which cannot be eliminated. The farm procedures and operations referred to are listed in Tables 1 and 2. We must ensure that the following prerequisites are in place. Ž1. The procedure is done for the right and acceptable reason. Farmers may perceive that procedures like tooth grinding ŽOrr et al., 1987. in sheep, tail docking in cows or castration in all animals intended for early slaughter are justifiable, but when they are shown that they are not, these procedures can be eliminated. On the other hand, farm operations like the Mules operation in sheep ŽShutt et al., 1987. or dehorning in goats
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
155
ŽButtle et al., 1986. can clearly be shown to be beneficial to the animal even if they are inevitably painful. Ž2. The correct method is used. There are usually several ways of performing a procedure, but the best method will depend on circumstances on a farm. Ž3. Equipment used must be appropriate for the procedure and properly maintained. Ordinary shears should not be used for the Mules operation in sheep, and the modified shears must be kept sharp to be acceptable. Ž4. Operators carrying out all farm operations or other procedures must be properly trained and assume responsibility for their actions. The skill with which a procedure is carried out will largely determine its acceptability, no matter how good the technique or equipment used may be. Ž5. The procedure has to be carried out at the right time. Dipping animals in midwinter, or when they have been driven long distances, or during prolonged wet weather, may make an otherwise very acceptable procedure unacceptable. Ž6. The procedure must be carried out on the correct class of animal. The age for castration is a good example. Mules operations need only be performed on very pleated breeds like the Merino. Ž7. Follow-up observation and treatment must be implemented. This implies both a standard procedure to be followed in all cases, as well as a knowledge of possible complications which can be anticipated and how these will be promptly and effectively countered. For example, myiasis may usually be expected after some techniques of tail docking and has to be prevented ŽLevot et al., 1989.. Ž8. Some form of monitoring will ensure that the minimum standards and conditions are maintained. 3.4. Certification Following on what has been said, the question arises whether animal ownership and its attendant actions and duties is an automatic right, or a privilege. Traditionally, it has been regarded as a right of all people but perhaps should rather be seen as a privilege which can be used by those who have the required facilities, knowledge and equipment. In the longer term we should consider making the care and control of animals subject to a system of licensing to help ensure that minimum standards of animal welfare are attained. While this may seem like a revolutionary proposal to some, it is the logical further extension of the consensus which is being built around our present concept of animal welfare. If people who wish to deal with animals were required to have a minimal level of knowledge as well as basic facilities before being allowed to do so, it would go a long way to restrict one of the main and continuing sources of animal abuse on farms.
References Adams, D.B., 1988. An approach to pain in research animals. Alternatives Lab. Anim. 16, 145–154. Barnett, J.L., 1988. Surgery may not be preferable to rubber rings for tail docking and castration of lambs. Aust. Vet. J. 65 Ž4., 131.
156
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
Buttle, H., Mowlem, A., Mews, A., 1986. Disbudding and dehorning of goats. In: Practice. Ewbank, R., 1988. Animal Welfare. In: Tindall, B. ŽEd.., UFAW Handbook: Management and Welfare of Farm Animals. Frazer, D., 1993. Assessing animal well-being: common sense, uncommon science. In: The Proceedings of the Conference on Food Animal Well-Being. USDA and Purdue University, Office of Agriculture Research for Programs, West Lafayette, IN, pp. 37–51. French, N.P., Wall, R., Morgan, K.L., 1994. Lamb tail docking: a controlled field study of the effects of tail amputation on health and productivity. Vet. Rec. 134, 463–467. Gibson, T.E., 1988. Animal Disease—A Welfare Problem? British Veterinary Association Welfare Foundation, London. Gonyou, H.W., 1994. Why the study of animal behaviour is associated with the welfare issue. J. Anim. Sci. 72, 2171–2177. Hargreaves, A.L., Hutson, G.D., 1990. The stress response of sheep during routine handling procedures. Appl. Anim. Behav. Sci. 26, 83–90. Levot, G.W., Hughes, P.B., Kaldor, C.J., 1989. Evaluation of dressings to aid healing of mulesing wounds in sheep. Aust. Vet. J. 66, 358–361. Lynch, J.J., Alexander, G., 1977. Sheltering behaviour of lambing Merino sheep in relation to grass hedges and artificial windbreaks. Aust. J. Agric. Res. 28, 691–701. McFarland, D., 1985. Oxford Companion to Animal Behaviour. Oxford Univ. Press, Oxford, UK. Mellor, D.J., Murray, L., 1989. Effects of tail docking and castration on behaviour and plasma cortisol concentrations in young lambs. Res. Vet. Sci. 46, 387–391. Oppenheim, J.J., Shevach, E.M., 1990. Immunophysiology. Oxford Univ. Press, Oxford, UK. Orr, M.B., Laws, A.J., Frisken, K.W., 1987. Sheep incisor cutters and grinders. New Zealand Vet. J. 35, 14–15. Rollin, B.E., 1993. Animal production and the new social ethic for animals. In: The Proceedings of the Conference on Food Animal Well-Being. USDA and Purdue University, Office of Agriculture Research Programs, West Lafayette, IN, pp. 3–13. Rowan, A.N., 1993. Animal well-being: key philosophical, ethical, political, and public issues affecting food animal agriculture. In: The Proceedings of the Conference on Food Animal Well-Being. USDA and Purdue University, Office of Agriculture Research Programs, West Lafayette, IN, pp. 23–35. Ryder, M.L., 1983. Sheep and Man, Dickworth. Shutt, D.A., Fell, L.R., Connell, R., Bell, A.K., Wallace, C.A., Smith, A.I., 1987. Stress-induced changes in plasma concentration of immunoreactive b-endorphin and cortisol in response to routine surgical procedures in lambs. Aust. J. Biol. Sci. 40, 97–103. Vincent, I.C., Michell, A.R., Leahy, R.A., 1993. Non-invasive measurement of blood pressure in dogs: a potential indicator of stress. Res. Vet. Sci. 54, 195–201. Vizard, A.L., 1994. Tail docking of lambs in the control of flystrike. Vet. Rec. 134, 463–467.
Management of pain in production animals G.F. Bath
)
Section Herd Health and Production, Faculty of Veterinary Science, UniÕersity of Pretoria, PriÕate Bag X04, Onderstepoort 0110, Pretoria, South Africa
Abstract The measurement and evaluation of animal welfare and pain is difficult and ultimately subjective. However, we are ethically bound to make our best assessment and reduce suffering. Evaluation can be made on the basis of chemical changes, behaviour, performance or extrapolation, and preferably a combination of these. Since pain in production animals cannot be totally eliminated, it has to be minimised by management, which must take into account the profitability and practicality of proposed actions and address all forms of pain and distress. This implies that behavioural, feeding, management and breeding aspects should also receive attention. Acts as well as omissions have to be assessed. Considerations in assessing actions or omissions include intention, alternatives, predictability, control measures, awareness, expertise, socio-economic situation and necessity. To control pain in production animals we must know the following: Ža. what is meant by pain and how it arises, Žb. the farming system, Žc. the animal and its needs, Žd. interventions, Že. alternatives available, Žf. production implications of advice, Žg. how to motivate farmers, Žh. how to arrange proper training, Ži. setting of minimum requirements, and Žj. monitoring of performance. Farmer support is essential for success. This should be achieved by persuasion arising from awareness—a positive interaction between specialists, veterinarians, farmers and staff is needed. Legal requirements and prohibitions should be a backup and not the central driving force. Minimising pain arising from any farm operation or procedure requires that the following are in place: Ža. it is done for the right reasons, Žb. it is done by the best method, Žc. the correct equipment is used, Žd. it is done at the right time, Že. it is done to the right class of animal, Žf. correct follow-up is carried out, and Žg. the persons are properly trained. The best way to entrench these principles is to make it a legal and ethical requirement that only persons who have the required knowledge, skill and equipment should be allowed to undertake farm operations and procedures. q 1998 Elsevier Science B.V. All rights reserved. Keywords: Animal welfare; Pain; Production animals; Management; Evaluation
)
Fax: q27-12-529-8315; e-mail: [email protected]
0168-1591r98r$19.00 q 1998 Elsevier Science B.V. All rights reserved. PII S 0 1 6 8 - 1 5 9 1 Ž 9 8 . 0 0 1 2 9 - 4
148
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
1. Introduction Every type of interaction between humans and animals is potentially subject to abuse, thus animal welfare has to address a wide field at many levels. It is the breadth and complexity of these interactions which leads to difficulties. In production animals, further complications include the underlying assumption that this interaction has to be to the net benefit of humans. Acceptable production and profit has to be maintained while measures to protect the animals are instituted. There are differences between species, breeds, individuals and production systems which must be taken into account. This contribution is written from the perspective of veterinarians in production animal practice, who must not only safeguard the welfare of animals but also that of their clients. Ž1. One of the chief problems inherent in evaluation of animal welfare or pain is that these are, to a large degree, perceptual and philosophical concepts ŽFrazer, 1993; Rollin, 1993; Rowan, 1993. which are not amenable to measurement in an accurate or objective way. Our attitudes to animal welfare are the result of a complex set of philosophical, religious, cultural, historical and socio-economic factors, as well as objective current scientific evaluation or measurement ŽMcFarland, 1985.. Ž2. A further difficulty lies in the many terms which are used, often interchangeably, in some contexts while in others they are taken to mean quite different things ŽEwbank, 1988; Gibson, 1988; McFarland, 1985; Ryder, 1983.. What is understood by a given term by one group of people can mean something quite different to others. This is certainly not simply a matter of semantics for fusty lexicographers. Without clarity of meaning there can be no clarity of purpose or a meaningful exchange of ideas. Words such as pain, suffering, discomfort, health, well-being, harmony and normality can mean whatever we choose unless there are certain specific meanings ascribed to them—at least within the context of animal welfare. Ž3. Finally, interconnected with the problem of terminology, we have the problem that there are many forms or types of pain, suffering and discomfort which must be properly recognised, differentiated and defined to make a rational and defensible approach to the management of pain possible ŽEwbank, 1988; Frazer, 1993; Rowan, 1993.. Thus, the problems which arise from our philosophy and our perception of pain and of animal welfare are intertwined with problems associated with the terminology we use and the types of pain which we identify or distinguish. While the ‘five freedoms’ ŽGonyou, 1994. ascribed to animals in many countries is a possible yardstick by which we may measure our progress, or a laudable idea to which we aspire, it needs to be remembered that for the vast majority of countries and peoples in the world, such ‘freedoms’ cannot even be guaranteed to people, let alone animals. Some form of pain in all living creatures is virtually unavoidable. We have to seek ways of minimising unavoidable pain and eliminating avoidable pain. In the final analysis we cannot really be certain of what animals feel and want. We have to avoid arrogant assumptions that we know what animals feel and need and rather adopt a more humble attitude of being custodians of the reasonable requirements of animals in our care. This does not mean we should not try to reduce suffering whenever and however we can. We
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
149
have to use the best current assessment of the status of animal welfare within the context of the situation in which it arises, even though we concede that our assessment remains party subjective. Our approach must be that whenever there is reasonable doubt, the benefit of the doubt should be in favour of the animal.
2. Evaluation If it is accepted that pain in its broadest sense is a perceptual concept arising from a complex interaction of factors then it follows that we must accept that it cannot be measured in the usual ways which scientists prefer. It is not the purpose of this contribution to review the current understanding of pain, but we do have to bear in mind that those measurable physiological, pathological and chemical processes which are described are only the underlying events which give rise to the perception of subjective feelings we call pain. The quality of subjective feelings is dependent on the level of consciousness and awareness of the animal, its psychology arising from its mental processes and emotions. An initial lesion has to lead to subjective feelings to qualify as pain. Further consequences of these feelings are memory, fear, association, anticipation, avoidance, distress and discomfort. 2.1. Causes There are different ways in which pain, distress and discomfort can arise in animals. These can be summarised as follows. Ž1. Physical. This is mainly the result of handling, farm operations and procedures, and results in physical pathologic changes. Ž2. Management. These are the problems which may be inherent in the housing, transportation and production methods in use. Ž3. Inherent behaviour needs. This group of factors may result in distress if it clashes with current management systems. Ž4. Feeding. Apart from the obvious component of undernutrition Žhunger, thirst., we must also consider overnutrition and imbalances. Ž5. Breeding. Only the genetic aspect is considered here. Genetic manipulation can result in severe though usually unintended side effects on animal welfare. Ž6. Chemical. A new but increasing area of concern is the effect of production-enhancing drugs or metabolic regulators on animal welfare. 2.2. Ranking More important perhaps is the need to rank the areas of animal welfare concerns in order of their degree of unacceptability. This hierarchy of reprehensibility is necessary if we are to make progress in some order of priority. A descending list of categories could be as follows. Ž1. Sadism Žcruelty.. Wilfully inflicting physical Žmutilations. or mental pain on animals with malicious intent, for the pleasure this gives to the person who inflicts it.
150
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
This is against the cultural norm and is done with the knowledge that it inflicts pain and suffering. Ž2. Abuse. The deliberate and wanton inflicting of pain usually involving fury or loss of control and excessive or undue action. This does not necessarily include malicious intent for the pleasure derived but is against the cultural norms and level of knowledge of the perpetrator. Ž3. Neglect. Pain or distress caused by lack of compassion, foresight, reasonable care and lack of responsibility. Although the person responsible does nothing active to cause pain or distress, his or her blameworthiness arises from the fact that the results of the omission are severe and could reasonably have been foreseen by a compassionate person. These actions are against the norms of that society. Ž4. Deprivation. This differs from the previous category in that the omission is essentially of something unknown or obscure to the person. The norms of the society and its level of knowledge may not automatically assume that omission could be harmful to the animal. Ž5. Ignorance. Acts of commission which are performed due to a lack of awareness or education, but usually within the norms of that society. Ž6. Cultural. Actions arising directly from a societal belief system which is deeply ingrained and thus completely acceptable to that community even though it may be reprehensible to others. Ignorance of the consequences or alternatives is often concomitant. Ž7. Necessity. Actions which involve unavoidable pain, but which are done for reasons which are clearly for the good of the animal or are unavoidable under the circumstances and are performed in the best way available ŽFrench et al., 1994.. Ž8. Good intent. The unforeseen consequences of actions, or the side effects resulting from actions intended to benefit the animal. 2.3. Measurement Measurement or assessment of pain has been attempted in several ways, each with their advantages and disadvantages. Ž1. Chemical. Indicators such as cortisol, endorphins, and lymphokines have been used or advocated ŽMellor and Murray, 1989; Shutt et al., 1987.. The problem is that changes in concentrations may result from many causes and they do not measure the perception of pain as such. They do help to underpin our assessment in an objective way. Ž2. Physiological. Blood pressure, heart rate and immunological measurements are similarly not necessarily or solely related to poor animal welfare, but may be used as research tools ŽOppenheim and Shevach, 1990; Vincent et al., 1993.. Ž3. Pathological. Measurement of lesions, disease incidence or organ changes suffer from the same problems as the previous two categories but may be useful in surveys and research ŽAdams, 1988; Gibson, 1988.. Ž4. Production. The recording of meat, milk, fibre or reproductive performance is of value in that good production cannot occur in the face of very poor welfare, but
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
151
sub-optimal welfare may not be reflected in lower production figures ŽGibson, 1988; Lynch and Alexander, 1977.. Ž5. Performance. The same may be said of performance in those animals which are measured in this way. Ž6. Behavioural. Well-researched ethograms Žnormal behavioural repertoire. are essential for this to be meaningful and do give a more objective measurement, even though indirect, of the perception of the animal ŽGonyou, 1994.. Ž7. Extrapolation. This clearly has many dangers, especially when extrapolation is made between very different families or genera. However, some degree of extrapolation is needed to improve our understanding of perceptions. Ž8. Contextual. Similarly, the basic viewpoint of the observer cannot be totally separated from the observations made. Each evaluation is made subject to the underlying culture, religion or philosophy of the individual and unless we acknowledge this, we fall into the error of according the assessment an objectivity which it lacks. Ž9. Combination. It should be clear that a combination of these ways of assessment is superior to any on its own, and we should try to combine assessments whenever possible. Ultimately we must concede that welfare evaluation is not a tangible measurement but a value judgement ŽBarnett, 1988.. 2.4. Considerations What then are the factors which we need to consider in assessing the acceptability or otherwise of actions or omissions which can affect animal welfare? These can be summarised as follows. Ž1. Intention of actions. Actions intended to hurt must obviously be viewed differently to those intended to help, improve production or performance, or looks, or where the result arises from no specific intention at all. Ž2. Alternatives available. If an action can be avoided by replacement and provided the alternative is both practical and cost effective, then this must be considered an important factor in determining acceptability. Ž3. Predictability of result. In some cases, an unacceptable outcome of a procedure is too unpredictable to be considered a necessary consequence and can therefore not be regarded as an automatic risk. Ž4. Control measures enforced. Often a particular operation can only be evaluated in the context of measures used, or available, to control its potentially unacceptable consequences. Ž5. Awareness of implications. It is only where people are fully aware of the direct and indirect results of their actions that they can be held fully responsible. Knowledge is implicit in blameworthiness. Ž6. Socio-economic levels. The actions or omissions of people living at or below a subsistence level, often with a poor education, must be viewed differently to those of people who are adequately educated and have a reasonable income. Animal welfare cannot be expected to be the top priority of people who are themselves starving. Ž7. Necessity of action. Under given circumstances an action or omission may be unavoidable, even if it does not contribute to animal welfare. It is unrealistic to expect
152
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
farmers to keep stock in optimal condition when droughts occur if this leads to financial disaster. Ž8. Expertise. Before taking on any aspect of animal care, it should be expected that persons are properly trained to do the work in the most humane way practical.
3. Management To control pain in production animals in an effective and reasonable way, we must gain the support of farmers who are responsible for animal welfare on a day to day basis. Winning their support is dependent on winning their confidence that what is proposed is reasonable, justified, practical and profitable. Those who wish to make real progress with controlling pain therefore need a very wide spectrum of knowledge to make good quality animal welfare a reality on farms. 3.1. Knowledge required Ž1. What is meant by terms like pain and distress, and how these arise from physical or management factors. Without a clear understanding of the types of pain and their causes, no defensible evaluation is possible. Ž2. The farming system and its day to day operation. No support will be forthcoming from farmers if proposals for animal welfare are hopelessly at odds with practical or financial realities. We must know the system’s goals, methods and measurements. Ž3. The farm animals and their needs have to be known on the basis of objectively measured ethograms as well as human-derived philosophical values ŽVizard, 1994.. Ž4. Farm operations, procedures and interventions used in practice have to be known as well as the reasons for their use. As can be seen in Tables 1 and 2, the list of interventions can be quite formidable, and some are far more acceptable than others ŽButtle et al., 1986; Hargreaves and Hutson, 1990.. Ž5. Alternative approaches or techniques must be known as well as their advantages and disadvantages, to properly weigh up their application in a given situation. Ž6. Implications of advice on animal production and profitability should be properly understood and evaluated in order to stand a chance of acceptance by farmers. Ž7. Persuading farmers of the moral rightness as well as the financial justification of procedures which are intended to promote animal welfare is crucial to long term improvement in the treatment of animals. This aspect will be further dealt with in Section 3.2. Ž8. Proper training of operators is essential to minimise pain and distress in animals. They must use not only the correct methods, but must apply them correctly and under the right conditions ŽFrench et al., 1994; Vizard, 1994.. Ž9. Minimum requirements or standards for each procedure or operation have to be set and made known. These standards have to be attainable under the practical conditions of the farming system.
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
153
Table 1 Potentially painful procedures performed in production animals by lay persons Procedure
Cattle
Sheeprgoats
Pigs
Electro-immobilisation Electric prodders Ear tags Ear notching Nose rings Branding Tattooing Dehorning Castration Hoof trimming Teeth cutting Mules operation Pizzle dropping Tail docking Teat amputation Shearing Artificial insemination Semen collection Milking Preputial flushing Dystocia relief Dipping Drenching Injection Ži.m. and s.c..
6 6 6 6 6 6 ? 6 6 6 x x x 6 6 x 6 6 6 6 6 6 6 6
6 6 6 6 x x 6 6 6 6 6 6 6 6 6 6 6 6 6 x 6 6 6 6
6 6 6 6 x x 6 x 6 6 6 x x 6 x x 6 6 x 6 6 6 6 6
Table 2 Consequences of poor techniques on animal welfare Sheep
Unfavourable consequences
Procedure
Short term
Long term
Ear tags Ear marks Dehorning Dipping Drenching Vaccination Castration Hoof trimming Teeth grinding Electro-ejaculation Milking AI Sponging Shearing Mules Tail docking Pizzle dropping Dystocia
Pain, bleeding Pain, bleeding Pain, bleeding Pain Pain Pain Pain, haemorrhage Pain, bleeding Pain Pain Pain Pain Tearing, bleeding Pain Pain Pain, bleeding Pain Pain, death
Crumpling, infections Neoplasia Blowfly, infection, scurs Cold, pneumonia, toxicity Pneumonia, abscesses Infection Tetanus, blowfly, infection, evisceration Joint infection Infection Fear Mastitis Infectionrperitonitis Infection, retention Clostridial infections and abscesses, blowfly Blowfly, skewing Tetanus, neoplasia, blowfly, rectal prolapse Ulcers Infection
154
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
Ž10. No system of laws will be of much use if its implementation is not effectively monitored. Thus, a practical monitoring system must be in place together with a programme for taking corrective action if necessary. 3.2. ConÕincing farmers Central to the success of a programme to improve the welfare of animals on a sustained basis is to change the attitudes of farmers. If they can be persuaded that measures to ensure animal welfare are morally justified as well as practical and economically defensible, we will have the best possible safeguard for animals. No law can be of much effect if it is not supported by the great majority of citizens. All too often, the emphasis in animal welfare is placed on legislation, restriction and punishment, rather than persuasion. Yet it is only by convincing those in charge of animals on a daily basis that a real and permanent change can be effected. If most farmers believe in the correctness of welfare safeguards, then these measures will become part of the ethos or culture of that community. Such a commonly held value system is a much more powerful motivator than the fear of prosecution. This does not mean that legislation and enforcement are unnecessary. Unfortunately there will always be a minority who will not respond to anything other than coercion and the threat of punishment. Laws are made for them. Persuasion must begin with awareness. We can expect the correct action from farmers only when they are aware that a given procedure may be unnecessary, or that there are better methods, or that it is unnecessarily painful. It is from this basis, which is where the practising veterinarian can play a pivotal role, that the farmer will be motivated by internal conviction to do things correctly. Specialist researchers have a role to play in laying the objective criteria on which farmer attitudes can be formed. It is through a sustained campaign directed toward farmers via meetings, publications, and especially the farmers’ own organisations that farmers can be convinced that our standpoint is justified. In countries where farmers make use of hired staff to assist with operations, these people must also be properly trained and motivated to improve conditions for animals. 3.3. Requirements for minimising pain We can assume that once we have eliminated all those aspects or practices of animal production which are not essentially part of the production system, we are left with the problem of minimising pain and suffering arising from those practices which cannot be eliminated. The farm procedures and operations referred to are listed in Tables 1 and 2. We must ensure that the following prerequisites are in place. Ž1. The procedure is done for the right and acceptable reason. Farmers may perceive that procedures like tooth grinding ŽOrr et al., 1987. in sheep, tail docking in cows or castration in all animals intended for early slaughter are justifiable, but when they are shown that they are not, these procedures can be eliminated. On the other hand, farm operations like the Mules operation in sheep ŽShutt et al., 1987. or dehorning in goats
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
155
ŽButtle et al., 1986. can clearly be shown to be beneficial to the animal even if they are inevitably painful. Ž2. The correct method is used. There are usually several ways of performing a procedure, but the best method will depend on circumstances on a farm. Ž3. Equipment used must be appropriate for the procedure and properly maintained. Ordinary shears should not be used for the Mules operation in sheep, and the modified shears must be kept sharp to be acceptable. Ž4. Operators carrying out all farm operations or other procedures must be properly trained and assume responsibility for their actions. The skill with which a procedure is carried out will largely determine its acceptability, no matter how good the technique or equipment used may be. Ž5. The procedure has to be carried out at the right time. Dipping animals in midwinter, or when they have been driven long distances, or during prolonged wet weather, may make an otherwise very acceptable procedure unacceptable. Ž6. The procedure must be carried out on the correct class of animal. The age for castration is a good example. Mules operations need only be performed on very pleated breeds like the Merino. Ž7. Follow-up observation and treatment must be implemented. This implies both a standard procedure to be followed in all cases, as well as a knowledge of possible complications which can be anticipated and how these will be promptly and effectively countered. For example, myiasis may usually be expected after some techniques of tail docking and has to be prevented ŽLevot et al., 1989.. Ž8. Some form of monitoring will ensure that the minimum standards and conditions are maintained. 3.4. Certification Following on what has been said, the question arises whether animal ownership and its attendant actions and duties is an automatic right, or a privilege. Traditionally, it has been regarded as a right of all people but perhaps should rather be seen as a privilege which can be used by those who have the required facilities, knowledge and equipment. In the longer term we should consider making the care and control of animals subject to a system of licensing to help ensure that minimum standards of animal welfare are attained. While this may seem like a revolutionary proposal to some, it is the logical further extension of the consensus which is being built around our present concept of animal welfare. If people who wish to deal with animals were required to have a minimal level of knowledge as well as basic facilities before being allowed to do so, it would go a long way to restrict one of the main and continuing sources of animal abuse on farms.
References Adams, D.B., 1988. An approach to pain in research animals. Alternatives Lab. Anim. 16, 145–154. Barnett, J.L., 1988. Surgery may not be preferable to rubber rings for tail docking and castration of lambs. Aust. Vet. J. 65 Ž4., 131.
156
G.F. Bath r Applied Animal BehaÕiour Science 59 (1998) 147–156
Buttle, H., Mowlem, A., Mews, A., 1986. Disbudding and dehorning of goats. In: Practice. Ewbank, R., 1988. Animal Welfare. In: Tindall, B. ŽEd.., UFAW Handbook: Management and Welfare of Farm Animals. Frazer, D., 1993. Assessing animal well-being: common sense, uncommon science. In: The Proceedings of the Conference on Food Animal Well-Being. USDA and Purdue University, Office of Agriculture Research for Programs, West Lafayette, IN, pp. 37–51. French, N.P., Wall, R., Morgan, K.L., 1994. Lamb tail docking: a controlled field study of the effects of tail amputation on health and productivity. Vet. Rec. 134, 463–467. Gibson, T.E., 1988. Animal Disease—A Welfare Problem? British Veterinary Association Welfare Foundation, London. Gonyou, H.W., 1994. Why the study of animal behaviour is associated with the welfare issue. J. Anim. Sci. 72, 2171–2177. Hargreaves, A.L., Hutson, G.D., 1990. The stress response of sheep during routine handling procedures. Appl. Anim. Behav. Sci. 26, 83–90. Levot, G.W., Hughes, P.B., Kaldor, C.J., 1989. Evaluation of dressings to aid healing of mulesing wounds in sheep. Aust. Vet. J. 66, 358–361. Lynch, J.J., Alexander, G., 1977. Sheltering behaviour of lambing Merino sheep in relation to grass hedges and artificial windbreaks. Aust. J. Agric. Res. 28, 691–701. McFarland, D., 1985. Oxford Companion to Animal Behaviour. Oxford Univ. Press, Oxford, UK. Mellor, D.J., Murray, L., 1989. Effects of tail docking and castration on behaviour and plasma cortisol concentrations in young lambs. Res. Vet. Sci. 46, 387–391. Oppenheim, J.J., Shevach, E.M., 1990. Immunophysiology. Oxford Univ. Press, Oxford, UK. Orr, M.B., Laws, A.J., Frisken, K.W., 1987. Sheep incisor cutters and grinders. New Zealand Vet. J. 35, 14–15. Rollin, B.E., 1993. Animal production and the new social ethic for animals. In: The Proceedings of the Conference on Food Animal Well-Being. USDA and Purdue University, Office of Agriculture Research Programs, West Lafayette, IN, pp. 3–13. Rowan, A.N., 1993. Animal well-being: key philosophical, ethical, political, and public issues affecting food animal agriculture. In: The Proceedings of the Conference on Food Animal Well-Being. USDA and Purdue University, Office of Agriculture Research Programs, West Lafayette, IN, pp. 23–35. Ryder, M.L., 1983. Sheep and Man, Dickworth. Shutt, D.A., Fell, L.R., Connell, R., Bell, A.K., Wallace, C.A., Smith, A.I., 1987. Stress-induced changes in plasma concentration of immunoreactive b-endorphin and cortisol in response to routine surgical procedures in lambs. Aust. J. Biol. Sci. 40, 97–103. Vincent, I.C., Michell, A.R., Leahy, R.A., 1993. Non-invasive measurement of blood pressure in dogs: a potential indicator of stress. Res. Vet. Sci. 54, 195–201. Vizard, A.L., 1994. Tail docking of lambs in the control of flystrike. Vet. Rec. 134, 463–467.