Effects of season on semen parameters and relationships between selected semen characteristics in Hypor boars (original) (raw)

Introduction Porcine ejaculate performance and semen quality depend on factors such as age, breed, feeding and nutrition, housing conditions, animal care, the way the semen is collected, and many others (1,2). Libido also affects ejaculate traits (3). Reproductive performance of artificial insemination (AI) in boars stems largely from semen quality, which is a function of the incidence of sperm cell morphological abnormalities (4). Besides the semen quality, the AI value of semen is additionally influenced by sperm morphometric features, their sizes, and shapes (5). One of the methods used to assess the biological value of semen and its suitability for inseminating females is examination of sperm morphology (6). In AI practice cases of reduced male fertility are observed. This may be due to seasonal factors such as temperature, humidity, and light intensity (1). The occurrence of seasonal variation in the frequency of morphological sperm anomalies may depend on the breed of pig (2). This is because of varying degrees of sensitivity among breeds to the effects of seasonal factors (7). The aim of this study was to determine the effects of seasonal factors on ejaculate physical traits and sperm morphology in Hypor boars and to establish correlations between some semen traits and year seasons. 2. Materials and methods The analysis involved 114 ejaculates collected from 12 Hypor boars utilized in three AI centers located in central Poland. Geographically the area ranges between latitudes 51°60′N and 52°50′N and between 19°10′E and 20°30′E. The average altitude of the area is 109 m above sea level. Four calendar-based seasons of the year were considered: