Failure of passive transfer: not just a dairy problem

Failure of passive transfer (FPT) has been extensively studied in dairy calves, however there is limited information concerning its prevalence or risk factors in suckler calves. Experiments exploring the impact of nutrition during late gestation on calf serum immunoglobulin concentrations have produced conflicting results, however none have used serum biochemistry to assess the nutritional status of the dam. Blood urea-N provides an indication as to the amount of Effective Rumen Degradable Protein (ERDP) in the diet, with results <1.7 mmol/l indicative of insufficient ERDP intakes. Blood urea-N results obtained during routine metabolic profiling of dry suckler cows are significantly lower than those of dry dairy cows (1.86 mmol/l vs. 2.27 mmo1/1), suggesting that ERDP supply during late gestation is worse in suckler compared to dairy cows. Here we report two case studies of spring calving suckler herds suffering from widespread neonatal calf disease, associated with FPT. Metabolic profiling of dry cows identified blood urea-N results <1.7 mmol/l in most cows sampled, whilst dietary supplementation with 1kg of either soya or beans resulted in a significant improvement in calf health, suggesting that insufficient dietary ERDP in late pregnancy is a potential risk factor for FPT in suckler calves.