不同生活条件下东方田鼠内脏器官比较

Microtus fortis calamorum inhabit on the beach of Dongting Lake from winter to spring, and hereafter are forced to migrate into rice field by flood and live there until autumn usually. We had compared the viscera indices (viscera indices=viscera weight/body weight×100g, including heart, lung, liver, spleen, kidney, stomach without content and testis) and intestinal tract length of M.fortis calamorum from the beach of Dongting Lake in spring, the rice field in autumn and laboratory populations. There were significant differences in the indices of liver, spleen, kidney and stomach of females among the three habitats, and so were the indices of heart, spleen, kidney, stomach and testis of males. The spleen indices of wild voles from the beach of Dongting Lake and rice field were conspicuously bigger than that of laboratory ones. The length of caecum, large+small intestine and total intestinal tract of wild voles were significantly longer than that of laboratory ones, and the length of caecum of voles from the beach of Dongting Lake were significantly longer than that of animals from the rice field. The results suggest that the bigger spleen of wild voles is probably an immunoreation to the infection of the animalcule and schistosome, and that the intestinal tract length is related to the food quality and the requirement of energy and nutrition. The caecum length extends with the increase of the cellulose in the food.