Variation in Colostrum Brix Values and Associations Between Initial Body Weight, Colostrum Intake and Piglet Survival from 24 h to Weaning in a Swedish Sow Herd

Colostrum is essential for neonatal piglet survival, but individual teat measurements may not represent sow-level mean Brix values. Brix refractometry provides an indirect on-farm estimate of colostrum IgG concentration. This exploratory study quantified Brix variation within and between sows and examined associations between initial body weight, sow Brix values, estimated colostrum intake, and survival from approximately 24 h to weaning. Colostrum was sampled from 28 sows in a Swedish high-health herd. A total of 410 teat samples were analysed and 373 piglets were weighed at colostrum sampling and followed until weaning. The mean sow Brix value was 27.6%. Approximately half the variation was attributable to differences between sows, with the remainder occurring between teats within sows. Empirical resampling analysis showed that sampling multiple teats improved the precision of sow-level mean Brix estimates; with five teats, 95.2% of estimates were within ±1.5 Brix percentage points of the observed sow mean. No clear association between sow-level Brix values and survival from 24 h to weaning was detected. Survival was associated with initial body weight, and the association with estimated colostrum intake depended on initial body weight, being strongest for piglets with lower body weight. Given limited sow numbers and single-herd design, these findings require multi-herd validation.