By John Wenz, Dale Moore and Sandy Poisson, College of Veterinary Medicine,
condensed from an article in the winter 2010 Veterinary Medicine Extension Ag Animal Health newsletter
PULLMAN – Newborn calves require antibodies derived from their mothers’ first milk – colostrum – for immunity during the first few weeks after birth. In the fall, WSU researchers completed a project to help state dairy farmers better assure that their calves are getting this immunity.
The goal of colostrum management is to provide a minimum of 150 g of IgG (immunoglobulins) to a calf within 24 hours of birth in order to assure adequate passive transfer of immunity. High quality colostrum should have at least 50g/L of IgG.
With help from producers and veterinarians, vet student Julie Caldwell during May-October collected serum samples from nearly 1,000 apparently health calves age 2-7 days on 56 farms across Washington. Colostrum management practices surveys were collected from 30 of the herds.
Findings showed that some colostrum management practices were associated with low IgG levels in newborn calves.
Calves were almost four times more likely to have inadequate levels if a milker was responsible for collecting colostrum versus other personnel, suggesting that milkers may be too busy to collect quality colostrum. WSU researchers recommended that designated personnel for colostrum harvest and feeding should be considered.
Calves were 2.3 times more likely to not have enough antibodies if colostrum quality was not evaluated versus evaluated by a colostrometer, suggesting that using a colostrometer would help eliminate first feedings of poor quality colostrum.
In addition to these findings, the study found that a simple Brix scale refractometer could be used to evaluate colostrum quality.
A Brix scale represents the percentage of sugar (sucrose) in a solution. Traditionally it has been used for fluids such as wine and honey. When applied to colostrum, it is used to approximate the dissolved solids content.