Variability of libido and properties of boar ejaculate

Abstract

The main objective of this study was to assess the variability of libido (duration of preparing to jump, T), the duration of ejaculation (E) and the properties of ejaculate: ejaculate volume (VOL), evaluation of density of ejaculate (DEN), evaluation of native sperm motility (NAT), evaluation of diluted sperm motility (DIL), as well as the number of doses produced per ejaculate (NPD) of boars reared under production conditions. The study included 8127 ejaculates of boars of the three breeds. Ejaculates were analysed during four annual seasons. Evaluation of variance was performed using mixed model. Average values of T, E, VOL, DEN, NAT, DIL and NPD were: 3.56 min, 6.09 min, 235.82 ml, 2.03, 3.98, 3.95 and 9.90 doses. Libido, ejaculation duration and characteristics of ejaculates varied under the influence of season, year, breed. All studied traits depended on the age of the boar when taking the ejaculate (P lt 0.001) except T and DEN (P>0.05). Differences in phenotypic property values were present between boars and between ejaculates and repeatability coefficient values for all studied traits ranged from 0.08 +/- 0.01 to 0.32 +/- 0.05. The association of the investigated boar traits was weak to strong (from -0.14 to 0.81; P lt 0.01 and P lt 0.001), with the exception of the association between T and NPD (P>0.05).