Good Colostrum Quality from 2nd Milking
Is it worth your time to check second milking from mature cows for antibody concentration? YES.
Dr. Noelia Silva-del-Rio, UC Davis Veterinary Medicine Extension specialist in Tulare CA, measured first and second milking from third or greater lactation Jersey cows. She had 134 first-milking samples and 68 second-milking samples.
43% of the second-milking samples contained IgG concentrations of 50g/L (the industry standard for acceptable quality for first feeding).
Given a shortage of first milking colostrum, Dr. Silva-del-Rio encourages producers to collect and test 2nd milking.
I agree. These data suggest that nearly one-half of the time the 2nd milking will be suitable for the first feeding of newborn calves.
Reference: California Dairy Magazine, May 2018, p16.