The effect of vitamin E supplementation on the libido and reproductive capacity of Large White boars

In this study the effect of dietary supplementation of vitamin E on libido, servicing capacity (SC), sperm quality and serum α-tocopherol of Large White boars was evaluated. Twenty four boars were divided into three groups of eight boars each. Groups were randomly allocated to treatment groups, i.e. 0, 40 or 70 IU of dl-α-tocopheryl acetate/kg of diet. Libido was defined as the time from intromission to ejaculation being recorded as the reaction time (RT) in minutes. Serving capacity (SC) was measured by number of mounts, combats, head-kicks, anogenital sniffs during a 30 min test period. Semen was collected by the use of an artificial vagina following the SC test, and afterwards analyzed for quantitative and qualitative parameters. The 70 IU supplementation of dietary vitamin E per kg diet to pigs resulted in the highest number of mounts, combats, head-kicks and anogenital sniffs with the shortest RT in comparison to the 40 and 0 IU vitamin E supplementation. The 70 IU vitamin E boar group produced semen with the highest semen volume, sperm cell motility, progressive movement, acrosomal normal apical ridge (NAR), percentage live sperm, sperm concentration per mL semen volume and total number of sperm per ejaculate and improved serum α-tocopherol concentrations (5.1 ± 0.5 μg/mL). Results suggest that supplementing 70 IU per kg α-tocopheryl acetate in boar diets appears to be most beneficial in optimizing libido and reproductive capacity in breeding boars.