Seasonal variations in semen parameters of Zulu rams preserved at 10°c for 72 h during breeding and non-breeding season

Abstract

The study was conducted to evaluate the seasonal variations in semen parameters of Zulu rams preserved at 10°C for 72 h. The study site was the Agricultural Research Council (ARC) Irene, during the breeding season and the non-breeding season. Zulu rams (n = 6, age = 3 years and average weight = 35 kg ±2.29) were used in this study. Semen was collected with the aid of artificial vagina. Macroscopic (volume and pH), microscopic (sperm concentration, progressions, velocities and velocity ratios and morphology) semen parameters were evaluated immediately after semen collection. Data were analyzed using General Linear Model (GLM) in Minitab 17®. Semen volume was higher during breeding season (0.97±0.25 mL) than non-breeding season (0.72±0.5 mL). Total sperm motility was higher (92.01±1.40%) at 24h during breeding season than non-breeding season (88.69±1.40%), thereafter declined drastically in both seasons. However, non-breeding season yielded a high progressive motility (50.86±1.63%, 33.77±1.63% and 27.56±1.63%) after 24, 48 and 72 h than breeding season (21.32±1.63%, 11.89±1.63% and 10.29±1.63%). It was concluded that, semen parameters from Zulu rams does vary with seasons. Nevertheless, despite seasonal variations observed, Zulu rams’ semen quality is acceptable in both breeding and non-breeding season hence can breed throughout the year. Notwithstanding, studies involving fertility are recommended and the nutrition effect of lambing during dry period should be considered.