Failure of passive transfer in dairy calves can lead to higher morbidity and mortality. Routine monitoring and feedback of colostrum protocols are critical to consistent high levels of passive transfer, says John Wenz,
Wenz gives this example of a passive transfer protocol and monitoring system for a 1,500-cow dairy:
Measure colostrum quality with a colostrometer at collection.
Only use colostrum in the “green” level (specific gravity >1.047 ~>52.4mg/ml IgG) for first feedings.
Label the colostrum with the cow’s identification (allows future disease tracking if necessary).
Give 2 quarts at birth and 2 quarts within 6 hours after birth.
Record who collected the colostrum, who gave it and the cow ID of the colostrum.
Calf total protein (TP) should be measured weekly (2 to 7 days of age) and a 5.5mg/dl cutoff used.
Record calf total protein in dairy management software.
Wenz suggests that the results are given to the calf manager who assigns names of workers to passive transfer failures for accountability. The calf manager also needs to investigate when failures spike and correct the problem (e.g. colostrometer broke so it wasn’t used, etc).
Wenz notes that at a dairy where this protocol was instituted, at the start of program there was about a 25% failure of passive transfer rate (many failures were <5.0mg/dl). After months on the program, the failure rate dropped to around 2% (failures were typically 5.0 to 5.3mg/dl).
“It’s important to remember that a 5.3 mg/dl cutoff correlates with 1000 mg/dl which is the minimum we would like to get into calves,” Wenz states. “Raising the cutoff to 5.5 will mean more calves will be classified at ‘failures’ or <1000mg/dl.” But, what are the consequences of being wrong (calling a calf a failure when she really isn’t)? “You push management to do better, which isn’t very costly and isn’t a problem unless you push too much and they get sick of hearing you,” Wenz says.
Wenz says that a colostrometer isn’t a perfect diagnostic tool; however, if implemented consistently as part of a colostrum management program that includes monitoring total proteins and providing feedback, it can work very well.