Cow-level factors associated with colostrum yield and quality of Holstein dairy cows

Abstract

Context Colostrum feeding and hence transfer of sufficient immunoglobulin G (IgG) is vital for protecting against disease in the neonatal calf. A wide range of variations exists in colostrum yield, IgG concentration and many factors that affect colostrum quality. Aims The current study aimed to determine the cow-level factors associated with colostrum yield, IgG concentration, and somatic cell score (SCS) in dairy cows. Methods Colostrum weight from 152 Holstein dairy cows from a commercial dairy herd was recorded, and SCS and IgG concentration were analysed. Cow-level factors were obtained from the on-farm computer software. The mixed linear model (PROC MIXED) was used to analyse the colostrum quality and production. Key results A calving body condition score (BCS) of <3 was associated with higher colostrum production and a lower colostrum IgG concentration. Furthermore, cows that lost their BCS during the dry period (DP) produced less colostrum IgG concentration than did cows that maintained or gained BCS. Cows with BCS of >3.5 at dry-off and calving had greater colostrum SCS. Cows that gained or lost BCS during the DP had the greatest and lowest colostrum SCS. Moreover, colostrum yield was highest in second-lactation cows, and cows with <45 day DP length (DPL) produced more colostrum with a higher IgG concentration. Higher-parity cows produced higher IgG-concentration colostrum. Colostrum SCS increased with increasing parity, and cows with >75 day DPL had the greatest SCS. Cows with >12 500 kg energy-corrected milk in previous lactation produced colostrum with the greatest IgG concentration and lowest SCS. Also, colostrum production was greater in singleton cows than in twinning cows, while colostrum SCS was lower. Moreover, cows that experienced clinical mastitis in the previous lactation had greater colostrum SCS than did cows without mastitis. Conclusions The results indicated that cow-level factors affect colostrum yield, quality, and SCS and highlighted the importance of routine colostrum testing. Finally, these results may help producers and advisers make decisions to improve colostrum production and quality. Implications Future research should focus on the effect of BCS change during the DP on colostrum yield and quality.