Effects Of6-MBOA On The Reproduction Of Brandt’s Voles(Lasiopodomys Brandtii)

6-Methoxybenzoxazolinone (6-MBOA), one of plant secondary metabolites (PSMs) particularly high in young plants of gramineae, was known to stimulate reproduction in some herbivore mammals. Brandt’s voles (Lasiopodomys brandtii) are dominant herbivorous rodents in Inner Mongolia grassland. In order to verify the hypothesis that6-MBOA stimulates reproduction of Brandt’s voles and elucidate the mechanism of outset of their breeding, we observed the effect of different doses of6-MBOA on sexual maturity of juvenile and reproduction of adult Brandt’s voles after repeated intraperitoneal injection. The results were as follows:1) When the juvenile voles were injected with6-MBOA for30days, males in high dose group were much heavier than males in control one. The serum testosterone in males of medium group was also higher compared to the control. However, injection of6-MBOA did not induce any change of testicular descent rate or other indices in males. The opening of vaginal orifice of females in medium dose group happened earlier than control group and the serum estrogen levels in the low dose group was significantly higher than that of control and high dose group.2) In adult male voles, short-term continuous injection of low and medium dose of6-MBOA increased their serum testosterone levels. The injection of medium dose of6-MBOA also enhanced immunoglobulin G in serum of males, while each dose of6-MBOA reduced the amount of serum melatonin. In adult females, the serum estrogen was much higher in medium dose group.3) Long-term injection of6-MBOA did not influence the body weight of adult males and females. But the testicular index in males of medium and high dose group was significantly lower than that of control group. The seminal vesicle storage index in the high dose group was lower than that of other three groups. Similarly, the serum testosterone and the thickness of the seminiferous epithelium in three treatment groups also significantly decreased. The uterine proportions in the females of low and medium doses groups were significantly higher than that of high dose group. The ovarian proportion of high dose group was significantly lower than that of the control and medium-dose group. FSH in the medium-dose group was significantly higher than the high-dose and low-dose group.All of these results showed that6-MBOA increases the sex hormone levels of juvenile Brandt’s vole and shortens the time required for the female vulvar opening. It seemed that6-MBOA may accelerate the maturity of Brandt’s vole pups. Shot-term treatment by6-MBOA may promote the breeding of Brandt’s vole by reduce the concentration of melatonin and increase the amount of sex hormones. Long-term given of6-MBOA reduced the concentration of testosterone and the thickness of the seminiferous epithelium of male Brandt’s vole.6-MBOA may reduced the weight of the female ovaries. Overall,6-MBOA may contribute in promoting reproduction of Brandt’s vole. Our work verified the hypothesis that6-MBOA could promote the reproduction of Brandt’s voles.