Stress and Reproduction in Reptiles

Inhibitory effects of stress on different aspects of reproduction are studied in a few species of reptile. Majority of studies report reduction in blood levels of androgen or estrogen following exposure to different stressors, viz. captivity, confinement, repeated blood sampling social stressors (exposure to dominant male/female) etc. Effect of stress on gametogenic activity has been studied only in female lizard, Anolis carolinensis and in both male and female lizards, Mabuya carinata. Stressors viz. chronic low humidity or over crowding inhibit vitellogenic follicular development in A. carolinensis maintained under stimulatory photothermal conditions. Similarly, exposure of the lizard M. carinata to repeated mild acute stressor viz. handling, chasing, and noise causes suppression of seasonal as well as FSH-induced germinal bed activity, vitellogenic growth of follicles, oviductal growth and serum levels of estradiol in females and spermiogenesis and serum levels of testosterone in males. These results in M. carinata indicate that stress-induced inhibition of gametogenesis is due to suppression of steroidogenic activity.