Relationship between birth order, birth weight, colostrum intake, acquisition of passive immunity and pre-weaning mortality of piglets

Abstract

This study investigates the relation between birth order (BO), birth weight (BW0), colostrum intake (CI), level of passive immunity and pre-weaning mortality of piglets. The animals used were 551 cross-bred piglets [Piétrain × (Large-White × Landrace)] born from 40 sows. Colostrum immunoglobulins G (IgG) determinations were made from 17 sows. Colostrum samples were obtained at birth of the first piglet then at 3, 6, 12, 24, and 36 h later, and on the first-two and the last-two piglets born. Serum IgG determinations from 68 piglets were made at 2d of age and at weaning. Individual CI was estimated from body weight gain. Relative birth order (RBO) and BW0 within-litter were weakly (R2<0.05) but positively correlated (p<0.01). Colostrum intake of piglets was independent from RBO (p>0.10) but increased by 26 ± 1.6 g per 100 g increase in BW0 (p<0.001). Serum IgG concentrations of the last two born piglets were 29.5% lower (p<0.01) than the first two born at 2 d of age, and 25% (p<0.05) at weaning. They were also lower at weaning than at 2 d of age (p<0.001). Serum IgG concentrations of piglets at weaning and at 2 d of age were positively correlated (R2=0.50, p<0.001). Within-litter, CI explained 11% (p<0.01) of the variation observed in piglets’ IgG at 2d of age. Mortality of piglets was irrespective of RBO (p>0.10). It was concluded that despite last-born piglets obtained less passive immunity than first-born, they were not at higher risk of dying before weaning. Major causes of mortality were low birth weight and insufficient colostrum (energy) intake.