Effect of sterilant phosphine oxide aziridine (MAPO) on reproductive function in male American red-eared terrapin Trachemys scripta elegans.
A total of 160 individuals of healthy adult male American red-eared terrapin Trachemys scripta elegans with body weight of (738.9±101.2) g was randomly divided into control group in which the terrapin was injected with 0.65% physiological saline solution (n=40), and three treated groups (n=40, for each group) in which the terrapin was injected intraperitoneally with 2 mL of phosphine oxide aziridine (MAPO) solution at a concentration of 0.1 g/L, 3 g/L and 10 g/L once in 2 day interval for 15 d to study the effect of MAPO on reproductive function in male terrapins and to explore an effective approach to prevent American red-eared terrapin from prevailing. The levels of hormones and relative proteins in serum and testis were measured in 16 d and 30 d, and testicular tissue structures were histologically observed by a microscope during recovery periods (30 d and 137 d). The results showed that high dose of MAPO led to death of the terrapin, and the level of sex hormone in serum and testis was not differed (P>0.05) in both low dose group and middle dose group compared with the control group in 16 d and 30 d, indicating that MAPO has no interference effect on hypothalamic-pituitary-gonadal axis. However, there was significantly lower serum inhibin B in middle dose group than that in the control group in 30 d, suggesting that sertoli cells were damaged. Moreover, the various pathological damages were observed in the testis in treatment groups during recovery periods, with increase in the spermatogenic cell gaps, and slightly toxic in low dose group. The spermatogenic cells were destructive, and dissolution in middle dose group, implying an irreversible damage. In conclusion, MAPO leads to infertility of male American red-eared terrapin by damaging testicular spermatogenic cells, sertoli cells, and the spermatogenic environment, so that MAPO can be used as a potential infertility drug to prevent the species from prevailing.