Social behaviour of domestic animals. IV. Growing pigs

Abstract

1. The normal pattern of social behaviour in growing Large White and Berkshire pigs is described. The pigs were observed from 8 to 16 weeks of age in pens of 6 to 10 pigs. Large Whites were more aggressive than Berkshires.2. Social rank was found to be positively correlated with initial weight.3. Initial weight and social rank both influenced growth; the relative effect of rank compared with that of initial weight was greater in the second month than in the first.4. The contribution of social rank to the total variance in growth over the 2-month period was estimated at about 13%.5. It is suggested that the use of individual housing in pig progeny test schemes may not be desirable because of the absence of social environmental effects.