The Combined Effect of IgG and Fe Supply and Feeding Management on Growth Rates of Calves on Eight Commercial Dairy Farms in Germany

During the first days of a calf’s life, the foundations are laid for successful growth and thus
also for the later performance of the cows. The aim of the present study was to analyze the impact
on the weight gain of newborn calves due to important management factors related to colostrum
supply, iron supply, feeding regime and microbial load at first feeding. In spring 2017, information of
123 Holstein calves were analyzed with regard to the colostrum supply and management factors on
eight commercial dairy farms located in Germany. Additionally, blood samples of newborn calves
were analyzed for total immunoglobulin G (IgG) and serum iron content. Furthermore, Brix analysis
and analysis of contamination by E. coli were performed on first colostrum samples from teats or
buckets. Average daily weight gain of calves at days 14 and 50 was calculated. The colostrum IgG
was estimated by Brix refractometer. The volume of initial colostrum supply and the time between
birth and colostrum intake significantly (p < 0.05) influenced the serum IgG concentration. The serum
IgG concentration, the serum iron concentration and the feeding regimen (restrictive or not restrictive
feeding) had a significant effect (p < 0.05) on daily weight gains. In conclusion, this study shows that,
in addition to a sufficient supply of immunoglobulins, other aspects, such as an adequate colostrum,
iron and milk supply, play an essential role in calf growth rates.