Assessing the welfare of growing dairy calves

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The objectives of this proposal are to answer the following broad questions:1. Do variations between individual calves in the occurrence of locomotor play and social play reflect variations in welfare due to illness, low energy intakes and/or poor growth? 2. How can we best measure locomotor and social play behaviour to assess the welfare of dairy calves? 3. Can the age at which calves reach certain stages in behavioural development (e.g. replacement of locomotor play by social play, first estrous behaviours, ability to eat solid feeds) be used to assess the welfare of growing animals? Public concern about farm animal welfare has led to welfare standards for farm animals and automated monitoring of behaviour has potential to enable behavioural measures to be used in animal welfare assessments. Poor dairy calf welfare has long term impacts on the productive life of adult cow, so it is important to have good methods to assess their welfare. Most measures used in welfare assessment identify poor welfare, but there is increased interest in using measures of good welfare. Among growing animals, play behaviour has been proposed as a good candidate for a positive welfare indicator. Dairy calves show a variety of locomotor and social play but we need better evidence of the link between play and animal welfare. Most schemes for assessing the welfare of growing animals are based on their state at a particular age. However, it is likely that the welfare of growing animals may be better assessed in terms of how they are developing. This proposed research involves a series of experiments on group housed dairy calves fed by automated feeding systems, to validate the use of measures of social and locomotor play as potential behavioural-based indicators of the good welfare of dairy calves. The link between the timing of the occurrence of various play behaviours, of the ability to eat solid feed and of first estrous will show the extent that the general timing of behavioural development is inter-related and affected by feeding and weaning strategies. The link with the age of later reproductive development may help us understand the problem of delayed reproduction of cattle.