One way to determine the adequacy of your colostrum feeding program is to run a total serum protein test.
Whenever total serum protein drops below 5 grams per deciliter, calves are at greater risk for health problems, says John Shirley, dairy scientist at Kansas State University. Total serum protein concentrations are associated with immunoglobulin absorption in calves.
A total serum protein test is a quick and inexpensive way to determine this, Shirley says. Although the test is often run by veterinarians, it can be performed on-farm by producers, as well, using a $300 refractometer that has been specifically calibrated for this purpose. (For more details, see "Try calf-side IgG tests" in the archives of the Dairy Herd Management Web site)
Perform the test on a random sample of calves, Shirley says. Be sure that all of the calves are within seven days of birth.