Applied Animal Behaviour Science, 20 (1988) 5-19 5 Elsevier Science Publishers B.V., Amsterdam -- Printed in The Netherlands The Scientific Assessment of Animal Welfare D.M. BROOM Department of Clinical Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge CB3 0ES (Gt. Britain) ABSTRACT Broom, D.M., 1988. The scientific assessment of animal welfare. Appl. Anita. Behav. Sci., 20:5-19 The welfare of an individual is its state as regards its attempts to cope with its environment. Welfare varies on a continuum from very good to very poor, and it can be assessed precisely. Information about what conditions might result in good welfare can be obtained from studies of preferences, but the importance of the preference to the individual must be assessed. Measures which show how poor welfare is when animals encounter short-term or long-term problems may be physiological, behavioural, or concerned with individual production or disease. Individuals vary in the coping methods which they use, so any one measure may indicate poor welfare and absence of evidence using one measure does not mean that there is no welfare problem. INTRODUCTION In order that proper decisions about issues concerning animal welfare can be accepted by the general public and by legislators, there is a great need for clarity in the terminology used when considering the subject and precision in the measurement of welfare. There is confusion concerning the different con- cepts of wildlife conservation, animal rights or human obligations towards an- imals, and animal welfare. This paper is about assessing welfare, but it is necessary to explain how the word welfare is used and how it is related to moral questions. The welfare of an individual is its state as regards its attempts to cope with its environment (Broom, 1986a). When conditions are difficult, individuals use various methods to try to counteract any adverse effects of those conditions on themselves. These attempts may be unsuccessful or they may succeed, but the effects of lack of success and the extent of what is done to try to cope can be measured. Hence welfare varies on a continuum from very good to very poor, and it can be assessed precisely. The assessment of welfare can be carried out in a scientific way without the involvement of moral considerations. The ques- 0168-1591/88/$03.50 © 1988 Elsevier Science Publishers B.V.