Effects of testicle insulation on seminal traits in rams: Preliminary study

To evaluate the effect of heat stress on sperm characteristics, as well as testicular biometrics and heat radiation, six breeds of rams: two Brazilian locally adapted breeds (Santa Ines and Bergamasca) and four exotic breeds (Dorper, Texel, Ile de France, and Hampshire Down) underwent scrotal insulation. The experiment consisted of pre-scrotal insulation (week −1), insulation (week 0), and post-insulation (week 1-11) phases. Insulation changed the scrotum and testicular measurements, the heat radiated from the gonads caused deleterious effects, both on the process of spermatogenesis and sperm maturation in the epididymis. However, all the characteristics studied showed reversibility at 11 weeks post-insulation, showing the ability of the seminiferous epithelium to react to the effects of environmental factors. The locally, adapted breeds were more resistant than exotic to testicular heat stress.