Selenium supplementation reduces induced stress, enhances semen quality and reproductive hormones in Saanen bucks

Abstract

The study was aimed to evaluate the effect of selenium (Se) supplementation on semen quality of Saanen goats following induced stress. Forty Saanen bucks were divided into two main groups: selenium supplementation and control. The groups were further subdivided into two groups each comprising of induced stress (injected with adrenocorticotropic hormone -ACTH) and not, leading to four groups (Se, Se + ACTH, ACTH and control). Semen was collected using electro-ejaculator. Selenium supplemented bucks received sodium selenite at two months interval while ACTH was administered at three weeks interval. Selenium supplementation led to higher (P < 0.001) ejaculate volume, sperm motility, concentration and viability regardless of induced stress. Se supplemented group produced creamy semen while Se + ACTH treatment led to thick milky semen with no significant difference (P> 0.05) between ACTH and control groups which led to milky semen. The semen pH from ACTH, SE + ACTH and control groups was significantly (P < 0.001) acidic compared to neutral (7.05 ± 0.05) pH from Se supplemented group. The percentage of primary sperm abnormalities were significantly (P < 0.001) lower in selenium supplemented group than the ACTH and control groups. Selenium supplementation significantly (P < 0.001) increased serum glutathione peroxidase activity, luteinising hormone and testosterone concentrations and reduced cortisol level. Therefore, oral supplementation with sodium selenite can be implemented in goats that are raised on selenium deficient soils to boost the oxidant status hence, lessen the stress effects by reducing cortisol levels and increasing glutathione peroxidase activity and eventually, improving semen quality.