Chronic excessive Zn intake increases the testicular sensitivity to high ambient temperature in Bama miniature pigs

Abstract Zinc (Zn) can accumulate in the body of wild animal and human through bio-magnification effects in the food chain to pose chronic toxicity. Male spermatogenesis was sensitive to excessive Zn and elevated temperature. This study aimed to examine whether or not excessive Zn intake caused testicular toxicity and estimate the interaction between Zn and high temperature (HT) in testes of Bama miniature pigs. Six-month-old pigs were pre-fed with or without additional Zn at 1500 mg/kg diet for 30 d and afterward subjected to HT at 40 °C for 5 h daily for 8 consecutive days. Blood samples were collected on d 31 and d 38 and testes were obtained on d 38 immediately after HT exposure. Our data showed both scrotal surface temperature (T) and body surface T increased after 5-h HT exposure (p