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.
