Swine

Genetic and non-genetic evaluation of perineal score and other factors associated with susceptibility to vaginal/uterine prolapse in commercial sows.

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Abstract

Pelvic organ prolapse (POP) has become a major issue in the swine industry in recent years, defined as uterine, vaginal, or rectal prolapse. The objective was to evaluate genetic and non-genetic factors associated with susceptibility to vaginal/uterine POP in crossbred sows. Data were collected on 3,983 LRxLW sows during late gestation on two commercial farms in the Midwest during the summer of 2023. All sows were housed in group pens 35 days after breeding, except for a subset of sows at one farm, which were placed in groups immediately after weaning and managed according to California Prop12 regulations with at least 2.23 m2 per sow, and moved into farrowing within 5 days prior to due date. Recorded data included parity (1-9), due date, body condition (1-5), caliper (5-24), and perineal scores (PS, 0=low risk, 1=moderate-to-high risk), and incidence of POP (0/1). The overall incidence was 2.4% for POP and 33% for moderate-to-high PS. Univariate logistic regression models estimated the effects of farm, housing type (conventional vs. Prop12), month, parity, body condition, and caliper scores on PS and POP. Parity 1 sows had significantly lower risk of moderate-to-high PS (p g) between PS and POP (0.74 ± 0.07), rg close to zero for POP with caliper (0.02 ± 0.22) and body condition (-0.02 ± 0.16), and strong rg between caliper and body condition (0.84 ± 0.05). Results suggest that early grouping of sows may increase risk of high PS and POP, and that late gestation PS can be a good indicator to identify sows at higher risk of POP for management, as well as a potential genetic indicator trait to select to reduce POP. Funding from National Pork Producers, Iowa Pork Producers Association, and Topigs Norsvin.

Keywords: 2026

How to Cite:

Veldhuizen-Haefner, T., Dunkelberger, J., Opschoor, C., Pham, H. & Dekkers, J., (2026) “Genetic and non-genetic evaluation of perineal score and other factors associated with susceptibility to vaginal/uterine prolapse in commercial sows.”, World Congress on Genetics Applied to Livestock Production Digital Archive 2026(1): 2286002. doi: https://doi.org/10.31274/wcgalp.23833

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