Heat Induces Oxidative Stress: Reproductive Organ Weights and Serum Metabolite Profile, Testes Structure, and Function Impairment in Male Cavy (Cavia porcellus)

The present study was designed to evaluate the effects of heat that induces oxidative stress on reproduction organ weight and serum biochemical, testes structure, and function in male guinea pig (Cavia porcellus). Forty-eight male guinea pigs with an average weight of 330.56 ± 23.62 g, aged 3–4 months, were distributed into four groups of 12 animals each. One group (control) was maintained to ambient temperature (20–25°C), while other groups (Groups 2–4) were exposed daily for 6 h, to 32 ± 1°C, 39±1°C, and 46 ± 1°C, respectively. All animals were sacrificed after 60 days' exposure and their reproductive characteristics values were determined. Results revealed a significant decrease (p < 0.05) of the weight of testes, epididymis, vas deferens, and accessory glands in cavies exposed to the highest temperature investigated (46 ± 1°C), compared to the control animals. There was a significant (p < 0.05) reduction of serum testosterone and LH levels in all heat stress-exposed groups (≥46 ± 1°C) when compared to the control group. Heat stress significantly (p < 0.05) decreased sperm mobility, sperm count, and testicular antioxidant enzymes, while increasing testicular malondialdehyde content. However, the serum level of HSP-40 increased in the animals exposed to 39 ± 1°C and decreased when the cavies were exposed to 46 ± 1°C. In conclusion, exposure to heat-induced oxidative stress results in impairment of reproduction organ weight and serum biochemical, testes structure, and function in male cavies.