Modifying the behaviour of singly caged baboons: evaluating the effectiveness of four enrichment techniques

Abstract

Techniques to reduce or prevent behavioural disturbances in singly caged primates vary in form and effectiveness, with some behaviours being exceptionally resistant to treatment. Seven singly caged adolescent male olive hybrid baboons (Papio hamadryas anubis) were selected for behavioural intervention because of their severe abnormal behaviour. A continuous, all-occurrence sampling method yielded mean durations of abnormal and normal behaviour throughout the 10-week study. Analysis of baseline behaviour verified substantial durations of abnormal behaviour (mean = 9.80 min per 30-min observation period). We tested the effectiveness of four enrichment techniques: positive reinforcement training (PRT), food enrichment, non-food enrichment, and social enrichment (pair/trio housing). Each of the four enrichment conditions was implemented for a two-week period, with 10 30-min observations conducted per subject. We used repeated-measures analysis of variance to examine differences in behaviour durations between baseline and each enrichment condition. The social enrichment condition resulted in the most positive behavioural changes, including increased social behaviour and near elimination of abnormal behaviours (mean = 0.69 min per 30-min observation). Significant reductions in total abnormal behaviour levels were also found for other types of enrichment, but only social enrichment and PRT were effective in reducing whole-body stereotypies. Cage-directed and self-directed behaviours significantly decreased, whereas activity levels significantly increased during all enrichment conditions. The results of this project indicate that animate enrichment (human or conspecific stimulation), as opposed to inanimate enrichment, provides optimal means of behaviour modification for singly caged baboons. These findings have substantial implications for the welfare of captive primates in promoting successful therapeutic approaches for the behavioural management of laboratory primate species and for allocating limited enrichment resources.

Stereotypic Behavior in Nonhuman Primates as a Model for the Human Condition

“…Instead, nonhuman primates are often trained through positive reinforcement to cooperate with husbandry procedures or to perform behaviors that are incompatible with the stereotyped behavior. Training involving behaviors such as holding a target, stationing, or presenting body parts has resulted in decreased levels of abnormal and stereotyped behavior in rhesus macaques, baboons, and chimpanzees (Baker et al 2009;Bourgeois and Brent 2005;Coleman and Maier 2010;Pomerantz and Terkel 2009). In a study of 12 chimpanzees trained to hold targets and present body parts, this decrease was observed throughout the day, even outside of the training sessions (Pomerantz and Terkel 2009).…”

Environmental enrichment in kennelled Pit Bull Terriers (Canis lupus familiaris)

“…This study therefore aimed to use behavioural measures to assess the effect of cheap and sustainable environmental enrichment on the welfare of kennelled Pit Bull Terriers that had been rescued from a dog-fighting ring in the Philippines. Dogs given coconuts were hypothesised to perform increased durations and frequencies of normal and active behaviours [31], such as walking and chewing enrichment, and behavioural diversity [27], whereas the dogs given cardboard beds and cardboard partitions were expected to show more relaxed behaviours [7,20], such as sitting or lying down for longer durations. All groups were hypothesized to show less distress-related behaviours such as yawning, panting and licking the cage [31].…”

“…Dogs given coconuts were hypothesised to perform increased durations and frequencies of normal and active behaviours [31], such as walking and chewing enrichment, and behavioural diversity [27], whereas the dogs given cardboard beds and cardboard partitions were expected to show more relaxed behaviours [7,20], such as sitting or lying down for longer durations. All groups were hypothesized to show less distress-related behaviours such as yawning, panting and licking the cage [31].…”