PSIII-11 Semen quality effect on conception rate among three purebred swine lines

Abstract

Abstract The objective of this study was to examine the relationship between semen quality and conception rate. There were 30985 Duroc, 15888 Landrace, and 18198 Yorkshire single sire, purebred mating observations with 880 Duroc, 508 Landrace, and 492 Yorkshire boars represented from March 2011 to July 2018. Data from each breed was analyzed using a logistic regression model with fixed effects of sow parity at time of mating, the number of breeding attempts for the sow, days rest of the boar, and days from collection to insemination, covariates of age at collection, motility, percent abnormal tails, and random effects of contemporary group, boar, and evaluator. For Duroc, increased percent abnormal tails decreased conception rate (odds ratio=0.99, P < 0.05), and more than 9 days rest resulted in lower conception rates compared to less than 5 days rest (odds ratio=0.85, P < 0.05). For all three breeds, inseminations occurring 2 days post-collection tended to result in lower conception rate compared to 1 day post-collection (Duroc, odds ratio=0.94, P < 0.1, Yorkshire, odds ratio=0.87, P < 0.1, Landrace, odds ratio=0.91,P < 0.05); however, for Landrace, inseminations occurring 4 days post collection resulted in higher conception rates compared to 1 day post-collection (odds ratio=1.16, P < 0.05). For Yorkshire, increased motility was associated with higher conception rates (odds ratio=1.02, P < 0.001). The effect of age at collection on conception rate was small, but significant for both Landrace and Duroc resulting in ~1% increase per year of age (P < 0.05). Boar and semen quality effects on conception rate were inconsistent across breeds, suggesting that optimizing conception rates across breeds could be difficult.