Vergleich der Immunokritmethode mit der Gesamtproteinbestimmung im Blutserum zur Beurteilung der Kolostrumversorgung neugeborener Kälber

Comparison of the immunocrit method with total protein determination in blood serum to assess the colostrum supply of newborn calves

The postnatal calf health is largely determined by the colostrum supply as they are born without a full working immune system. Many studies have shown how calves with unsufficient colostrum supply (failure of passive transfer, FPT) suffer from higher morbidity and mortality, lower weight gain and worse performances altogether than those with good supply. Nonetheless, current studies show that many calves are not sufficiently supplied with colostrum. Therefor a frequent review of the colostrum management is highly recommended for every farm. This should not only include controls of colostrum quality but also determine the amount of immunoglobulin as well as the total protein in the calves' serum. As for the total protein, a value of 55 g/l is advised for the first days after the first colostrum intake.
The objective of this study was the validation of the immunocrit method as a possible way for controlling the calves' supply with colostrum. Therefore, 500 calves were tested in the time from August 6th 2018 to February 21st 2019, coming from 50 different farms in Lower Saxony and Norh Rhine Westphalia, Germany, determining their immunocrit and serum total protein as a refence, by using the biuret reaction. The collected data show a high correlation between the two values (r = 0,89), thus validating previous studies describing the immunocrit method as a suitable technique to examine the colostrum supply (Mortola et al. 2020; Vallet et al. 2013). However, the high effort and a missing added value make this method of little practical use.
In this study, the amount of colostrum ingested within the first 24 hours of life, the feeding technique, the milk yield, the maternal vaccination of the cows and the iron supply of the calves have shown to be significant influencing factors on the immunocrit. It was also shown that the survival rate of calves with a high immunocrit is higher than that of calves with a low rate. The present study shows how the colostrum supply of newborn calves is significant for their further health and lifetime performance. Significant factors for the ammount of immunocrit could determined. Farms with high rates of morbidity and mortality in calves should prove these factors in order to optimize their calf rearing.