USDA's "Heifer Calf Health and Management Practices” report of U.S. dairies shows that 19.2% of heifer calves have a failure of passive transfer of immunity based on IgG serum testing.
"Calves allowed to nurse the dam were more likely to have failure of passive transfer than calves that did not nurse [and were hand fed,]” reports a USDA stakeholder's announcement.
The results are from Dairy 2007 study of USDA's Animal and Plant Health Inspection Service (APHIS) National Animal Health Monitoring System (NAHMS). The majority of operations, 59.2%, hand-fed colostrum to calves from bottles or a bucket. But on average, calves received hand-fed colostrum 3.3 hours after birth. Veterinarians and calf specialists typically recommend feeding colostrum within an hour of birth to optimize absorption of critical nutrients and to transfer immunity.
The NAHMS study also found that 7.8% of pre-weaned heifers died as did 1.8% of weaned heifers. Scours, diarrhea and other digestive problems accounted for 56.5% of the deaths of pre-weaned heifers. Respiratory disease was the largest killer of weaned heifers, at 46.5%.