Neonatal Colostrum Intake in Dairy Heifers Can Affect Lactation Performance

Passive transfer of immunity through colostrum is known to improve short-term health in neonatal dairy calves, but its long-term effects remain poorly understood. Lactational programming proposes that bioactive components in milk and colostrum induce epigenetic changes that influence future performance, although this concept has received limited attention in dairy cattle. The aim of this study was to investigate potential associations between neonatal colostrum intake, as estimated by serum total protein (STP), with subsequent growth, reproductive performance, and milk production in 2661 dairy heifers from five pasture-based dairy herds in South Australia. Blood samples collected within the first 1–7 days of life were used to measure STP as an indicator of passive immunity transfer, and consequently, colostrum intake. Heifers with adequate passive transfer (STP > 50 g/L) produced 0.5, 2.4, and 0.7 kg more milk per day during their first, second, and third lactations, respectively, than heifers with inadequate passive transfer (STP ≤ 50 g/L). In contrast, no meaningful associations were identified between neonatal STP and yearling weight, age at first or subsequent calvings or calving intervals. These findings suggest that adequate colostrum intake enhances lifetime milk production and provide evidence supporting lactocrine programming in dairy cattle.