ASSESSMENT OF THE RELATIONSHIP BETWEEN PHYSICAL EJACULATE PARAMETERS AND THE SEXUAL ACTIVITY OF LANDRACE BOARS

The study involved 11 Landrace boars, aged 8-9 months and used for insemination purposes. Each boar was assessed four times for its sexual activity: at the beginning of breeding service and after 3, 6 and 9 months of service. Ejaculates were collected for the assessment of sexual activity parameters. Physical parameters of the ejaculates were subsequently analysed. Pearson’s linear correlation was used to calculate coefficients of phenotypic correlation between sexual activity levels and physical parameters of the ejaculates. Ejaculate parameters were shown to depend on the sexual activity of boars, as identified after 3, 6 and 9 months of insemination service. Moreover, it was determined that the degree of this interrelation increases along with age and development. After 3 months of service a correlation was identified between the sperm count in the ejaculate and the number of times the boar mounted the phantom, as well as a correlation between sperm motility and the time necessary for effectively mounting the phantom. After 6 months of service a correlation was observed between sperm concentration and both the time of ejaculation and total semen collection time. After 9 months of service the interrelation between ejaculatory efficiency and the level of sexual urge was the most prominent and was expressed in a high coefficient of correlation between ejaculation duration and the total semen collection time and both the volume of the ejaculate and sperm concentration.