Effectiveness of On-Farm Tools for Measuring Colostrum Quality
That is the title of a report given at the Western Canada Dairy Seminar by Amanda Bartier and others in 2013.
After examining the data from 572 colostrum samples one of the conclusions they reached was that the current cut points for "good" colostrum may be lower than desirable for achieving successful passive transfer of immunity.
Assessment Current Authors' Suggested
Tool Cut Points Cut Points
Colostrometer 50mg/ml 80mg/ml
Brix refractometer 22 24
"Implications: The cut points for identifying good quality colostrum may be different than previous literature suggests. This study also indicates that although the colostrometer is a more accurate tool over a range of IgG levels the Brix refractometer is useful at confirming truly good quality colostrum. Overall, using either tool is more beneficial than not measuring colostrum quality at all prior to feeding."
Bottom line for me? Adopt a colostrum management protocol that includes measuring quality.
BTW, it is good to be back at the vet clinic after two weeks on the lecture circuit in UK and a full week of really bad jet lag.