In vitro boar fertility during summer and autumn season

Abstract

A primary objective of this study was to determine the effect of breed, frequency of utilisation, boar age and season on following sperm characteristics: volume of ejaculate (ml), sperm concentration (x1000000 spermatozoa/ml), total count and count of functional spermatozoa in ejaculate (x1000000000 spermatozoa), motility of spermatozoa in native ejaculate and after dilution (%), number of produced doses, percent of dead and viable spermatozoa. Research included 4 boars of Landrace breed (n=40 ejaculates) and 13 boars of Large White pig (n=89 ejaculates). Ejaculates were analyzed during two seasons (summer and autumn), a dividing line being a calender start of autumn. Interval between two mounts was observed on two levels: ≤7 and ≥ 8 days. The assessment of the effect was done by means of a General Linear Model procedure. Breed and frequency of utilisation did not affect an average expression and variability of sperm characteristics. By increasing boar age by one day the volume of ejaculate increases by 0.142 ml. In ejaculates taken during autumn season a higher concentration of sperm per ml of ejaculate by 53.38x1000000 spermatozoa (p=0.033) was determined. Higher motility (p<0.001) of native i.e. diluted semen of 5.7, i.e. 8.2% was determined in ejaculates taken during summer season. A higher percent (+13.47%; p<0.001) of dead spermatozoa was determined in ejaculates in autumn season.