Maternal Impact on Serum Immunoglobulin and Total Protein Concentration in Dairy Calves.

For dairy calves, sufficient supply with high-quality maternal colostrum is crucial to achieve adequate passive transfer of immunoglobulins. This observational cross-sectional study aimed to determine the influence of the prepartum metabolic status of dams on the serum immunoglobulin and total protein concentrations of their dairy calves, taking other relevant management factors into account. A total of 551 cows and their calves from 124 German dairy farms were included. Blood and urine samples of the cows were sampled 1 to 3 weeks before the expected calving date. Two generalized linear mixed effects regression models were fitted to the data. An increase in a dam's prepartum serum non-esterified fatty acids concentration was associated with greater serum immunoglobulin concentration in her calf. Calves of herds with established birth monitoring at night showed greater serum immunoglobulin and total protein concentrations. Calves being fed more than 2 L of colostrum and higher Brix values for colostrum were related to greater serum immunoglobulin and total protein concentrations in calves. In conclusion, there is evidence that, besides timely and sufficient supply of high-quality colostrum to new-born calves, the prepartum metabolic status of cows and birth monitoring impact the passive transfer of immunoglobulins.

Associations between the metabolic status of the cow and colostrum quality as determined by Brix refractometry.

Supplying newborn calves with immunoglobins is critical for their health and a daily challenge in the dairy industry. Among various factors determining colostrum quality, the prepartum metabolic status of the cow might be of particular importance. The objective of this observational cross-sectional study was to evaluate relationships between cow-level variables and the colostrum quality as determined by Brix refractometry. A total of 873 cows of varying breed and parity from 124 German dairy herds were included in the study, and blood and urine samples were taken 3 to 1 wk before the expected calving date. Effectively, samples were collected on average 8.2 d (geometric mean) before calving, ranging from 2 to 45 d. The final variable set included body condition score, lameness score, breed, parity, vaccination of the cow, the activity of glutamate dehydrogenase and aspartate aminotransferase, the urine concentration of creatinine, net acid-base excretion, the serum concentration of cholesterol and calcium, and the difference in albumin and total protein concentration. Generalized linear mixed effects regression models with hierarchically structured random effects (cow within herd) using the maximum likelihood method were fitted to the data to identify associations between the Brix value as an outcome and cow-level variables as predictors. Cows entering second parity had lower Brix values compared with cows entering third or greater parity, and prepartum vaccination of cows led to higher Brix values compared with nonvaccinated cows. Cows with a moderate to high lameness score had lower Brix values than cows with low-grade lameness. An increase of glutamate dehydrogenase serum activity and serum calcium concentration were associated with lower Brix values, whereas an increase in the difference of total protein and albumin serum concentration led to higher Brix values. In conclusion, the metabolic health of the cow affects colostrum quality and may cause failure of passive immunoglobulin transfer as well as impaired calf health.