Improving the Welfare of Laboratory-Housed Primates Through the Use of Positive Reinforcement Training: Practicalities of Implementation

Abstract

Whilst there has been a recent increase in interest in using positive reinforcement training for laboratory-housed primates, there remains a reluctance to put into practice training programmes. Much of this reticence seems to stem from lack of expertise in the running of training programmes, and a perception that training requires a large time investment, with concurrent staff costs. The aim of this thesis was to provide practical recommendations for the use of training programmes in laboratories, providing primate users and carestaff with background information needed to successfully implement training programmes whilst improving the welfare of the animals in their care. Training was carried out with two species, cynomolgus macaques (Macaca fascicularis) and common marmosets (Callithrix jacchus) in three different research laboratories to ensure practicability was as wide ranging as possible. Training success and the time investment required were closely related to the primate's temperament, most notably an individual's willingness to interact with humans, in both common marmosets and cynomolgus macaques. Age and sex however had no effect on an individual's trainability. The training of common marmosets was more successful than that with cynomolgus macaques, possibly due to differences in early experience and socialisation. Positive reinforcement training helped both species to cope with the stress of cage change or cleaning, with the monkeys showing less anxiety-related behaviour following the training programme than before. Involving two trainers in the training process did not affect the speed at which common marmosets learned to cooperate with transport box training, but behavioural observations showed that initial training sessions with a new trainer led to animals experiencing some anxiety. This however was relatively transient. Whilst the training of common marmosets to cooperate with hand capture was possible, there seemed little benefit in doing so as the monkeys did not show a reduced behavioural or physiological stress response to trained capture as compared to hand capture prior to training. However strong evidence was found that following both training and positive human interactions the marmosets coped better with capture and stress was reduced. It is recommended that an increased use of early socialisation would benefit laboratory-housed primates, and would also help improve the success of training. Further, the time investment required shows that training is practicable in the laboratory for both species, and that positive reinforcement training is an important way of improving their welfare likely through reducing boredom and fear.