Abstracts of presentations: Abstracts 70-88

• Publisher: John Wiley and Sons
• Year: 1998
• Tongue: English
• Weight: 77 KB
• Volume: 45
• Category: Article
• ISSN: 0275-2565
• DOI: 10.1002/(sici)1098-2345(1998)45:2<193::aid-ajp6>3.0.co;2-r

✦ Synopsis

Approximately 65% of captive lowland gorillas regurgitate and reingest their food on a regular basis, but the behavior has never been reported in wild populations. As a foodrelated behavior, regurgitation and reingestion (R/R) may be influenced by nutritional factors. As more information concerning wild, western lowland gorilla diets becomes available, the comparatively low fiber content of most captive gorilla diets and the inclusion of animal products such as milk, eggs, and meat, are under question. To determine the behavioral effects of removing milk (a low-fiber, animal product) from gorilla diets, an ABA withdrawal study was conducted with 19 gorillas at Zoo Atlanta. Milk was replaced with an equal volume of diluted fruit juice during the afternoon, indoor meal. Thirty-six hours of behavioral data were collected during the post-prandial period using 5 min focal sessions with instantaneous point sampling at 15 sec intervals. Results showed that feeding on forage material substantially increased while drinking water, resting, and social behavior decreased during treatment. In addition, there was a 25% decline in R/R during the treatment period as compared to baseline, although individual differences emerged. Removing milk from captive gorilla diets may therefore contribute to a reduction of R/R during the period following meals in which milk is currently offered. Further investigation is needed to determine whether the effect is enhanced when milk is removed without liquid replacement.