Bayesian inference of inbreeding effects on litter size and gestation length in Hungarian Landrace and Hungarian Large White pigs

The effects of litter and dam inbreeding on the number of piglets born alive (NBA) and on the gestation length (GL) were analyzed for 39,798 Hungarian Landrace (141,397 records) and 70,356 Hungarian Large White (246,961 records) sows. Bivariate repeatability animal models were used, applying a Bayesian approach. Differences in pedigree completeness (complete generation equivalents) were accounted for. Litter and dam inbreeding effects (per 10% inbreeding) on the NBA resulted in negative regression coefficients for Hungarian Landrace (− 0.162 to − 0.047 and − 0.203 to − 0.042) and Hungarian Large White (− 0.231 to − 0.100 and − 0.282 to − 0.111) populations. The litter inbreeding increased the GL for Hungarian Landrace and Hungarian Large White populations, but the magnitude of the effect was less then 0.01 days per 10% inbreeding. The effects of dam inbreeding on GL were negligible.