Determining sow and piglet characteristics associated with stillbirth and pre-weaning piglet survival in F1 Large White × Landrace pigs in South Africa
Traits associated with stillbirths and pre-weaning piglet survival
DOI:
https://doi.org/10.62310/liab.v6i2.396Keywords:
Litter size, Sow mothering ability, Colostral immunoglobulins, Piglet mortality, Within-litter variationAbstract
Pre-weaning mortality remains a persistent constraint in commercial pig production systems worldwide, affecting herd efficiency and economic returns. The aim of the study was to determine sow and piglet characteristics associated with stillbirth and pre-weaning piglet survival in the F1 Large White × Landrace pigs in South Africa. Secondary data were extracted from the farm database and the study included records from 360 sow litters with 5845 piglets. The sow characteristics analysed included parity, litter size, length of gestation, farrowing weight, litter weight variation, average litter weight and sow mothering ability. Piglet characteristics included birth weight, suckling period, sex, fostering status and colostrum immunoglobulin (IgG) concentration. Two separate multivariate logistic regression models were fitted: (1) predictors of stillbirth, (2) predictors of survival to weaning. Sows were categorized into quartiles for each of the independent variables to quantify the relationship to stillborn rate or survival to weaning. A general linear model for a binomial response was fitted to analyze the difference in stillborn and pre-weaning survival between the quartiles of each respective variable and Fisher’s LSD was used to separate significantly different means (p < 0.05). The study revealed that parity, average litter weight, litter size, gestation length, and farrowing weight were significantly (p < 0.05) associated with the prevalence of stillbirths. Parity, litter size, length of gestation, farrowing weight, litter weight variation, average litter weight, sow mothering ability, fostering status, and colostrum immunoglobulin (IgG), were significantly associated with pre-weaning piglet survival (p < 0.05). Stillbirth was highest in sows with low farrowing weight (< 222.25 kg; 8.88%), intermediate gestation length (114–115 days; 4.47%), and small litters (≤ 14 piglets; 5.65%). Piglet survival was highest in larger litters (> 17 piglets; 92.18%), higher-parity sows (≥ 4; 80%), and heavier piglets (> 1.4 kg; 81.35%). The logistic regression models confirmed litter size, gestation length, and farrowing weight as key predictors (p < 0.05). These findings suggest that optimizing piglet survival requires a multifactorial approach that combines sow and piglet characteristics, and management practices to enhance production efficiency and reduce piglet mortality.
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Copyright (c) 2026 Rivoningo N. Mabunda, Mamokoma C. Modiba, Khathutshelo A. Nephawe , Hezekiel Mpedi, Takalani J. Mpofu
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Accepted 2026-08-05
Published 2026-09-24
