The Effect of a Short-Term Biomedical Research Protocol on Stereotyped Rocking in Young Chimpanzees
Chimpanzees are sometimes housed in conditions of restricted social contact during use in biomedical research, a practice that may adversely affect their behaviour. This study measured the impact of such conditions on levels of stereotyped body rocking in six young, nursery-reared chimpanzees.
Subject age at the beginning of the biomedical research protocol ranged from 1.1 to 3.8 years. Over a six-month period the subjects were moved to a different facility. During this time they were used in a biomedical research study which involved some periods of single housing. They were then
returned to their original facility. The percentage of time subjects devoted to stereotyped rocking was measured for 36 weeks before and 36 weeks after participation in the biomedical protocol. Data on body rocking were also analysed for a post-test control group of animals (n = 9) who had
a similar history of hand-rearing, but who did not leave the facility to participate in a biomedical research study. The behavioural analyses included 263 hours of focal animal observational data and revealed that the experimental subjects devoted equivalent amounts of time to rocking before
and after participation in the biomedical research protocol. The experimental subjects and the control subjects showed similar levels of rocking. These findings indicate that participation in this particular short-term biomedical research protocol did not affect the expression of stereotyped
rocking in chimpanzees.