Key Laboratory of Evidence of Science and Technology Research and Application, Gansu Province (Gansu Institute of Political Science and Law), lanzhou 730070, China
We investigated the effects of chronic environmental stresses, including living space, group size, and external interference, on the physiological and biochemical behaviors of Chinese tree shrews. Our results revealed that when tree shrews were housed in smaller cages, the average body weights were decreased significantly, while the cell numbers of the blood and sternal bone marrow were increased significantly, as compared to those housed in larger cages. Also, testicular shrinkage and atrophy, penis droopy, and decreased sexual activity were observed in the male tree shrews in smaller cages. Tree shrews treated with reserpine in the intervention group had reduced irritability, and the external environmental stimuli only affected slightly the living behaviors, wrestling, body weight, blood and sternal bone marrow cells, sexual organs, and sexual behaviors.
