The impact of using Dried Distillers Grains with Solubles (DDGS) as a substitute for concentrate feeds during the dry period on the quality of bovine colostrum and the IgG levels in their calves' serum.

The aim of the study was to determine the changes in the composition and physicochemical properties of cow's colostrum and the levels of immunoglobulin G in the serum of their calves, depending on the inclusion of dried distiller's grains with solubles (DDGS) as a substitute for concentrate feeds in the diet during the dry period. Sixty cows were divided into four groups: Group C - traditional TMR feed, Group I - modified feed with the inclusion of DDGS at 10% of dry matter, Group II - DDGS inclusion increased to 15% of dry matter, Group III - DDGS inclusion increased to 20% of dry matter. Colostrum samples were collected from all cows during the first full milking after calving. Blood samples were taken from all cows after calving and from their calves on days 3rd and 30th of life. No significant changes were observed in the basic composition of cows' colostrum. The levels of amino acids were significantly lower in DDGS groups. There was an increase in a concentrations of IgG, IgM, IgA, lactoferrin, K, Na, and proportion of α-casein and κ-casein in the colostrum of cows receiving DDGS. The total serum protein content was lower in cows receiving DDGS, despite a higher content of IgG. On the 3rd day of life, significantly higher levels of total protein and IgG were found in the calves' serum. Based on the results optained, it can be concluded that the use of DDGS in a cow's diet during the dry period as a substitute for concentrated feeds does not reduce the colostrum quality. However, including DDGS at a level of 15% DM in the cows' diet results in higher IgG content and, consequently, a higher level of passive immunity in their calves.