Semen quality characteristics of post-pubertal rabbit bucks fed ginger rhizome meal based diets

Abstract

This study was conducted to determine the effect of ginger rhizome meal on libido and semen characteristics of post-pubertal rabbit bucks reared in Nigeria. Thirty - six crosbred rabbit bucks aged 10 - 12 months  with mean body weight of 1470.70g were divided into 4 treatment groups of 9 each, which were further replicated thrice and fed diet supplemented with ginger rhizome meal at 0 g (T₀), 5g (T₅), 10 g (T₁₀) and 15g (T₁₅) per kg feed fed ad libitum for 10 weeks. Prior to the first six weeks of the study, a two week period of training was used to train the bucks to ejaculate artificially into artificial vagina. Semen was collected between 8.00 am and 9.00 am and taken the laboratory for analysis within 30 minutes of collection. Sexual drive (libido) of the rabbit bucks was determined by in­troducing the female into the hutch containing the experimental rabbit bucks, and recording the reaction time (seconds) of the rabbit bucks with a stopwatch. Data collected were subjected to analysis of variance. Results revealed that semen colour changed from cream milky to milky. Similar (p>0.05) semen pH and sperm concentration values were obtained among the dietary groups. Bucks in T₀ (control) and T₅ treatment groups had significantly (p<0.05) higher semen volume than those bucks in T₁₀ and T₁₅ groups. Total spermatozoa concentration values of bucks on T₀ (0.11 × 10⁹/ml) and T₅ (0.10 × 10⁹/ml) treatments were significantly higher (p<0.05) than those bucks on T₁₀ (0.07 × 10⁹/ml) and T₁₅ (0.07 × 10⁹/ml) treatments. Sperm motility and live sperm cells (%) declined (p<0.05) progressively in a dose dependent manner. Percent dead sperm cells were significantly (p<0.05) lower for bucks in control group than those in T₁₀ and T₁₅ groups. Reaction time had a dose-dependent increase, though the observed difference was not significant (p>0.05). It was therefore, concluded that supplementation of bucks’ diets with ginger rhizome meal at 10g/kg feed and 15g/kg feed for a period of 10 weeks decreased semen volume and total sperm concentration but increased the number of dead sperm cells in comparison to the control groups. It was also found sperm motility and number of live sperm cells decreased significantly in bucks that received ginger rhizome meal at 5g/kg feed, 10g/kg feed and 15g/kg feed in comparison to the control groups.