Stanton PhD Thesis final_docx - Atrium - University of Guelph

emoved from the time budget (Wood-Gush et al., 1984). This allows bonds to form between
unrelated animals. When 9 male and 9 female prepubertal calves were studied within a large
extensive herd where they had minimal human contact, four calf pairs were found. A pair of
calves was defined as two animals that mutually preferred to spend time with each other in each
of the six months of this study. Interestingly, on average pair members differed in age by 5 days
despite the fact that there was an age range of two months within the group (Reinhardt et al.,
1978). This indicates that it is likely that age and developmental stage are very important in the
development of partners within a herd; Reinhardt and colleagues (1978) concluded that social
contact between calves is not random, but also highly unpredictable.
Play behaviour is one aspect of social behavior. Calves move in and out of play behavior
quite rapidly and under natural conditions perform this behavior many times throughout the day
(Reinhardt et al, 1978). Once play is initiated it appears to elicit this behavior in conspecifics not
involved in the original event (Vitale, 1986). Play behaviour occurs between both sexes with
males being more active and more likely to be involved in social activity than the females in the
group (Reinhardt et al., 1978; Vitale, 1986). There has been interest in using play behavior as an
indicator of positive welfare. Play is predicted to be an indicator of positive welfare based on
decreases in play behavior during aversive situations, such as hunger and pain. For example, play
behavior is decreased in lambs following castration (Thornton and Waterman-Pearson, 2002) and
in groups of dairy calves during weaning (Krachun et al., 2010).
Negative Social Interactions
In modern dairy systems, cattle are kept in larger groups than they would normally
encounter in feral or range conditions. In the mountains of Japan, a feral herd of cattle had an
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