社鼠和褐家鼠消化道长度和重量的季节变化

测定了浙江金华的社鼠和褐家鼠消化道长度和重量的季节变化。野生社鼠消化道各器官无论长度不审重量都有明显季差异，在寒冷的冬季具有相对较大的小肠、大肠、盲肠、雄性社鼠的消化道长度在秋季由于食物条件的改善而明显下降，但雌性社鼠由于在秋季仍有繁殖负担，其消化道长度下降不明显，而家栖的褐家鼠只有总消化道、小肠和大肠的长度有季节差异，冬、春季高于夏、秋季。消化道形态季节变化与温度、食物条件和繁殖有关。

SEASONAL VARIATIONS IN LENGTH AND WEIGHT OF THE DIGESTIVE TRACTS IN RATTUS NIVIVENTER CONFUCIANUS AND RATTUS NORVEGICUS

We observed the seasonal variations in length and weight of the digestive tracts of Rattus niviventer confucianus and Rattus norvegicus from Jinhua, Zhejiang. Significant seasonal variations in length and weight of the digestive tracts were discovered in Rattus niviventer confucianus . For this species, small intestine, caecum and larger intestine which were relatively heavier in cold winter, significantly decreased in length of the digestive tracts in male rodents in autumn due to better food conditions. However, such decrease was not discovered in the female counterparts of the species due to the breeding state. For Rattus norvegicus , we discovered that seasonal variation in length of the total digestive tract, small, and larger intestines was greater in winter and spring than that in summer and autumn. Our results indicated that temperature, feeding habit and reproductive status might be responsible for the seasonal variations in the morphology of the digestive tracts of the two rodent species.