Influence of colostral quality on serum proteins in dairy calves raised in smallholder farms in Thailand.

The objective of this study was to analyze the influence of colostral quality on serum proteins in calves. Samples were collected from visited farms in Kasetsart University Veterinary Teaching Hospital at Kamphaeng Saen and Nong Pho Animal Hospital. In total, 35 dairy farms contributed 80 dams and calves' samples. Colostrum samples from 80 dairy cows and blood samples from their calves were taken to evaluate colostral immunoglobulins (Ig) and immunoglobulin G (IgG), and calf serum protein and IgG. Total colostral Ig, colostral and serum IgG, and serum protein were measured by a colostrometer, single radial immunodiffusion, and refractrometer, respectively. Immunoglobulin G and serum protein concentrations increased in the 1st day after birth, and maximum concentrations were seen in the 2nd day and then decreased in the 7th and 14th days. Average ± SD total colostral IgG concentrations at calving date and at 1 and 2 days after calving were 93.85 ± 33.89, 37.11 ± 23.51, and 17.23 ± 9.4 mg/mL, respectively. The profile of total Ig and IgG concentrations in colostrum had a similar pattern, with the maximum concentrations obtained in calving date and rapidly decreased thereafter. Low IgG concentrations were seen in the 7th and 14th day after calving. The calves that were fed with high quality colostrum had higher serum protein at 1 day of age, 7.49 ± 1.01 g/dL, than calves fed with low quality colostrum, 6.40 ± 0.86 g/dL (P < 0.01). The increase in serum protein after first colostrum feeding of high and low quality colostrum was 1.55 ± 1.07 and 0.81 ± 0.69 g/dL, respectively (P = 0.02).