Stretching Your Supply of High Quality Colostrum
By using Brix values for colostrum we can consider a strategy for stretching our supply of high quality colostrum.
Okay, just how to do this?
First, test colostrum to estimate concentration of antibodies. On a Brix refractometer if we get a reading between 22 and 23 we estimate that roughly 4 quarts (3.8L) of colostrum will deliver about 200 g of IgG's.
Second, recent research suggests that overfeeding IgG's at one feeding does not improve circulating antibodies in the calf's blood. That is, once the threshold of IgG delivery is reached feeding more colostrum will not improve the calf's immunity status.
Now, let's say we have colostrum that tests 25 or 27 Brix. Rather than feeding the standard 4 quarts these research findings suggest we can cut back that volume and have some leftover colostrum for the next calf. All we need is a tidy chart that tells us based on the Brix reading how much less colostrum needs to be fed.
Too bad. I don't know of any such chart. However, the principle is still valid. If we our high quality colostrum supply is really tight one workable solution may be to cut back our 4 quart volume to only 3 quarts for average size large breed newborn calves when we have extra-high testing colostrum.
In order to stretch our supply of high quality colostrum for first feeding newborn calves, when we have colostrum testing above 23 Brix consider reducing the volume fed from the "normal" 4 quarts to a lower volume to reach an acceptable threshold of IgG delivery.
Reference: Reiff, O.M. and Others, " Does considering immunoglobulin G concentration alone constitute a physiology-based colostrum management program?" Journal of Dairy Science 101:Supplement 2 Abstract M35, p19.