Effects of tannic acid on food intake and micro-morphology of the small intestine in Lasiopodomys fuscus

This study aimed to evaluate the effects of tannic acid on food intake and micromorphology of the small intestine in mature Qinghai voles (Lasiopodomys fuscus). We examined changes in body weight, food intake, villus length, and crypt depth in 24 male Qinghai voles under diets containing 0%, 3%, and 6% tannic acid (TA). The results showed that under the action of TA, the body weight of Qinghai voles changed significantly, and the individual body weight of each group showed significant differences. On day 60 of the experiment, no significant differences were identified between the body weights of voles in the 6% TA and 3% TA groups, which were significantly higher than that of voles in the control group. Tannic acid also had a significant effect on vole food intake. At the beginning of the experiment, the food intake in the control group was significantly lower than that in the 3% TA group but significantly higher than that in the 6% TA group. On day 7, food intake in the 3% TA group was significantly lower than that in the control group. On days 28, 42, and 60, the food intake of voles in the 3% TA and 6% TA groups was significantly higher than that in the control group. Tannic acid had significant effects on villus length and crypt depth of the voles’ small intestines, which were significantly longer in the TA groups than in the control group. The results suggest that TA could inhibit the feeding of Qinghai voles, and the inhibitory effect decreased over time. After Qinghai voles were adapted to TA, TA could promote the feeding of Qinghai voles, but this promotion was not achieved by changing the structure of the small intestine.