抄録
From the viewpoint of animal welfare, it is necessary to modify the time budgets of captive monkeys closer to those of monkeys in the wild. The present study aims to clarify the factors that influence the speed, quantity, and rhythm of feeding behavior in captive Japanese monkeys. We devised a new panel cage which consists of unit panels to easily change the arrangement and size of cages. Two adult female monkeys served as subjects in the following three experimanta. Experiment 1 introduced a “food puzzle”, the 18×18mm square mesh, in which skillful manipulation with the fingers was required to retrieve the food. The food puzzle reduced the speed of foraging. Experiment 2 explored the effect of housing two monkeys in one cage with two living units. In general, the two monkeys spent the night in the same living unit, while they spontaneously separated from each other in the different units during feeding time. Experiment 3 tested the effect of introducing a mirror to a monkey. The introduction of the mirror elicited grimaces, lipsmacking, and other social reactions in the beginning. The mirror facilitated feeding behavior as in “social facilitation”, where the presence of another individual facilitates feeding behavior. In conclusion, the three experiments clearly demonstrated some of the factors influencing the parameters of feeding behavior in captive monkeys.
