Does co-supplementation of zinc, manganese, and copper affect plasma testosterone, sperm quality, and anti-oxidant enzyme activities of ram?

Adding trace minerals to animal diets has a positive impact on reproductive performance. This study aimed to investigate whether supplementing zinc, manganese, and copper affects the testosterone level, sperm quality, and anti-oxidant enzyme activities in rams. Ten mature Afshari rams (2.50 years old; weighing 100 ± 3.29 kg) were fed a nutritionally adequate diet for 11 weeks, half of which receiving a sulfated zinc, manganese, and copper in their daily concentrates (supplemented group), while the other half served as a control group receiving no mineral in the concentrates. Ejaculate volume, as well as sperm concentration, motility, viability, morphology, and membrane integrity were assessed. From week five onwards, all parameters were significantly higher in the supplemented group. Additionally, the percentage of abnormal sperm was lower, anti-oxidant enzymes activities in the seminal plasma were improved, and plasma testosterone concentration was higher in the supplemented group compared to the control group. However, alkaline phosphatase activity was not significantly different. Furthermore, seminal plasma concentrations of copper, zinc, and manganese at the end of the study were higher in the supplemented group compared to pre-treatment levels, while these parameters were decreased in the control group. Overall, co-supplementing copper, zinc, and manganese in rams maintained the sperm quantity and quality, as well as seminal plasma anti-oxidant capacity, emphasizing the importance of studied elements in ram reproduction.