LAUSR

Vaginal and rectal prolapse incidence has been increasing in the commercial breeding sow population in the U.S. This has resulted in increased sow breeding mortality rates in the U.S. in recent years. The objective of the present study was to estimate the potential role that genetics plays in the prolapse incidence of the U.S. commercial sow population. Data from 22,577 LW x LR crossbred sows from commercial breeding herds were used in this study. Genetic parameters for prolapse incidence were estimated using AIREMLF90 and THRGIBBS1F90 where an animal and threshold models were implemented. The fixed effects in the models included: contemporary group as farm and year-month of removal and removal parity. A random effect for sow and pedigree based relationship matrix was also included in the model. The highest rectal and reproductive tract prolapse incidence were observed in the 1st and 2nd parities. Moreover, sows born in 2013 were investigated greatest incidence of both prolapse incidence. Heritability estimates for prolapse incidence were 0.03 and 0.003 by using the animal and threshold models. The results from this study indicated that there is very little of any genetic impact on the prolapse incidence. Pork producers identify the environmental effects contributing to prolapse incidence.