The influence of temperature on the feeding behavior of Peltocephalus dumerilianus (Testudines Podocnemidae)

Abstract

Objective: To analyze the feeding behavior of 50 Peltocephalus dumerilianus hatchlings (Testudines Podocnemididae) under different temperature conditions in laboratory. Materials and methods: The individuals for this experiment were obtained by incubation in the laboratory. They were divided randomly into 5 groups. Temperature trials were conducted for 2 months with 3 repetitions per week, using electric heaters. Temperatures were recorded continuously using a digital thermometer - 10 to + 60°C (± 0.1°C). Temperatures were increased 0.25°C every 10 minutes until reaching the selected temperature, which was then maintained for 60 minutes for each test. The temperatures selected for tests, were 26°C, 30°C, 34°C, 38°C, with an ambient temperature of 26.8°C. We evaluated: feeding duration (in minutes), consumption (in volume), the time which turtles began agonistic behavior, and two characteristic displays: biting and disputes over food. Results: In general all parameters were significant, the higher the temperature the longer the time of ingestion; the lower the temperature the lower the consumption volume; the lower the temperature the greater the time to initiation of agonistic behavior, demonstrating an inverse relationship. Conclusions: There was a direct relationship between environmental temperature and feeding processes. Temperature was also related to basic aspects of behavior during agonistic displays.