Semen Quality Evaluation in Boars Used for Artificial Insemination in Commercial Piggeries in Imo State

Artificial insemination is an increasingly adopted reproductive technology in commercial pig production in South East Nigeria, with Imo State among the leading pig-producing states in the region. The success of artificial insemination programmes depends critically on the quality of boar semen used for processing and cryopreservation. This study evaluated semen quality parameters in boars used for artificial insemination programmes at commercial piggeries in Owerri and Okigwe, Imo State. Semen was collected weekly from 20 Landrace and Large White boars over a 12-week period using the gloved hand technique. Ejaculate volume, sperm motility, progressive motility, sperm concentration, morphology, and viability by eosin-nigrosin staining were assessed immediately after collection. Mean ejaculate volume was 218 mL with significant variation between breeds. Progressive motility was significantly higher in Large White boars at 78.4 percent compared to 73.1 percent in Landrace boars. Sperm concentration averaged 245 million per millilitre. Morphological abnormalities were present in a mean of 12.3 percent of spermatozoa, with head defects being most common. Semen collected during the dry harmattan months showed significantly lower progressive motility and higher morphological abnormality rates compared to wet season collections, suggesting a seasonal effect on spermatogenesis. These findings provide baseline semen quality data for Landrace and Large White boars in Imo State and highlight the importance of seasonal management in artificial insemination programmes. Keywords: semen quality, boar, artificial insemination, Imo State, sperm motility.