The effect of melatonin on sperm quality and testicular size of normospermic and pathospermic rams in the anoestrous season

The aim of this study was to investigate the effects of melatonin implants on sperm quality and testicular size of normospermic and pathospermic rams in the anoestrous season. The study was carried out on a total of fourteen Konya Merino rams. As a co nsequence of preliminary experiments, eight rams were found as normospermic and six rams as pathospermic. Both the normospermic and the pathospermic r ams were divided into two groups with regard to spermatologic features and testicular size. Four normospermic and three pathospermic rams were treated with melatonin i mplant (Regulin(R)) and control groups were sham-treated. Semen samples of each ram were started to be collected after 5 weeks of the melatonin applic ations twice a week for 6 weeks. Semen samples were examined for volume, in dividual motility, sperm concentration, live/dead and abnormal sperm rates. Scrotal circumference and testes volume of the rams were measured within 1 5-day intervals during the study. Sperm motility and abnormal spermatozoon rates were found to be higher in t he semen samples obtained from normospermic melatonin implanted rams than t hose of normospermic control rams. Significant variations in all spermatolo gic characteristics studied were found between pathospermic melatonin impla nted rams and those of pathospermic control rams. Scrotal circumferences an d testes volumes were found to be significantly higher in all melatonin imp lanted rams than in control rams. Our results indicated that melatonin implants have positive effects on sper m quality and increased the scrotal circumference and testes volume of both normospermic and pathospermic rams in anoestrous seasons.