Epididymal Sperm Characteristics, Testicular Morphometric Traits and Growth Parameters of Rabbit Bucks Fed Dietary Saccharomyces cerevisiae and/or Zinc Oxide

Abstract

ABSTRACT The objectives of this twelve-week feeding trial were to determine the effects of dietary Saccharomyces cerevisiae and/or zinc oxide on epididymal sperm characteristics, testicular morphometric traits, and growth parameters of bucks. 16 (New Zealand White) bucks 16-wk-old, weighing 2.8kg were randomly allotted to one of 4 treatment groups. Each treatment was replicated four times, with 1 buck per replicate, in a completely randomized design (CRD). Each treatment group was randomly assigned to one of the four commercial experimental diets designated thus: TA = control diet with no additives, TB = 0.12g/kg Saccharomyces cerevisiae, TC = 150mg/kg zinc oxide and TD = 0.12g/kg Saccharomyces cerevisiae +150 mg/kg zinc oxide. Although treatment had no effect (p>0.05) on final body weight, average daily weight gain and feed conversion ratio, epididymal sperm characteristics and testicular morphometric traits differed significantly (p<0.05). Bucks on TB(Saccharomyces cerevisiae-based diet) had improved (p<0.05) sperm concentration, motility and live sperm, tubule diameter, epididymal volume, volume fraction of duct, and total duct volume, but decreased testicular volume. Bucks fed TA (control diet) had improved volume fraction of tubule but recorded the highest incidence of head and tail sperm abnormality. Though, TC(zinc oxide-based diet) enhanced (p<0.05) seminal vesicle volume, sperm pH was better among bucks fed TD (Saccharomyces cerevisiae + zinc oxide-based diet). It can be concluded that dietary inclusion of Saccharomyces cerevisiae at 0.12g/kg of feed improved epididymal sperm characteristics and testicular morphometric traits of rabbit bucks.