Non-Genetic Factors Affecting some Colostrum Quality Traits in Holstein Cattle

The aims of this study were to determine the effects of dry period length (DPL), average daily milk yield (ADMY), parity and calving season on some colostrum quality traits in Holstein cows. The material of the study consisted of 51 Holstein Friesian cows. The specific gravity of colostrum, fat, non-fat dry matter (NDM) and protein percentages were measured for colostrum produced at 2, 24, 48 and 72 h after birth. The specific gravity of colostrum (colostrum quality) was determined using a colostrometer. The effects of DPL, ADMY, parity and calving season on the specific gravity of colostrum (colostrum quality) were found to be significant at the 2nd h after birth. Colostrum quality of cows with ADMY low (Group 1) and high (Group 2) were found to be 1.065 +/- 0.0015 and 1.055 +/- 0.0016 g/ml, in postpartum 2nd h, respectively. Colostrum quality of cows with long DPL (1.064 +/- 0.0013 g/ml) was found to be higher than those with short DPL (1.054 +/- 0.0017 g/ml) at the 2nd h after birth. The effect of parity on the specific gravity was found to be significant at the 2nd h (P<0.01), 24th h (P<0.001) and 48th h (P<0.05) after birth. In addition, the effect of calving season on fat percentage was found to be significant at the 24th and 48th (P<0.05). The highest NDM and protein in colostrum were determined in cows with low ADMY while the least NDM and protein in colostrum were found in cows with short DPL.