Dietary composition influences sperm quality and testis damage via endoplasmic reticulum stress in lambs.

Background: The metabolic impacts of including soya meal, wheat gluten and corn gluten in the diet of male lambs could influence their reproductive performance. Objectives: An experiment was carried out to assess the effects of corn gluten, wheat gluten and soya meal on the reproductive system of male lambs. Methods: Twenty‐four male Morkaraman lambs, aged 9 months, were utilized in this study and were fed experimental diets for 56 days. The lambs were divided into a control group (soybean meal + safflower meal), a corn group (corn gluten) and a wheat group (wheat gluten). Results: The serum follicle‐stimulating hormone level of the control group was significantly higher and tumour necrosis factor‐alpha (TNF‐α) level was lower than the wheat and corn gluten groups (p < 0.05). The lowest malondialdehyde level in testicular tissue was observed in the control group, whereas the highest was in the wheat gluten group (p < 0.05). The glutathione level in the control group was significantly higher than in the other groups (p < 0.05). The corn gluten group showed the highest CHOP and IRE1 levels; the lowest Bcl‐2 levels and the highest IL‐1B and P2 × 7R levels were found in the wheat group; and the lowest TNF‐α levels were in the control group (p < 0.05). Additionally, the study revealed that diet had a significant impact on spermatological parameters of the testis such as diameter, volume and weight (p < 0.05). Conclusions: These results concluded that the inclusion of different protein sources in the diet of reproductive male lambs affects the metabolism of testicular tissue. [ABSTRACT FROM AUTHOR]