Abstract #M70

# M70
Impact of colostrum pasteurization on serum concentration of selected cytokines.
Marta Terré*1, Anna Bassols2, Maria Vidal1, Jordi Galian3, Alex Bach4,1, 1Institut de Recerca i Tecnologia Agroalimentàries, Caldes de Montbui, Spain, 2Universitat Autònoma de Barcelona, Bellaterra, Spain, 3Granja Murucuc, Gurb, Spain, 4Institució Catalana de Recerca i Estudis Avançats, Barcelona, Spain.

Levels of IgG are usually used to evaluate colostrum quality. However, there are other bioactive substances such as cytokines, which pasteurization may also affect. The objective of the study was to evaluate the effects of colostrum pasteurization (60°C during 60 min) on performance and cytokine plasma levels. Sixty dairy Holstein male calves (44.9 ± 0.38 kg BW) from birth to weaning (56 d of age) were enrolled in the study. Calves were born in a commercial dairy farm, and they were offered within the first 2 h after birth 4 L of colostrum either non-pasteurized (NP) or pasteurized (P). All colostrum was previously frozen at −18°C within the following 2 h after being milked. All calves received the same MR feeding program and the same concentrate starter during the preweaning period. Animals were weighed weekly, intakes recorded daily, and blood samples obtained at 24 h after the colostrum was fed, and at 2 and 5 week of age to determine general biochemistry. Fecal and respiratory scores from 1 to 3 were recorded daily. Fifteen calves per treatment that consumed the 4 L of colostrum offered were selected to determine IgG, TNFα, and IL-1β in serum samples. Data were analyzed with a mixed-effects model with repeated measures being pasteurization and time the main effects of the model. There were no differences in growth rate among treatments, neither in the gain to feed ratio nor in the incidence of fecal and respiratory scores. Although colostrum IgG concentration was similar in both NP and P colostrum (2,366 ± 251.5 mg/dL), greater IgG and a tendency in greater TNFα serum concentrations were observed in NP compared with P colostrum fed calves (3,356 vs 3,183 ± 0.053 mg/dL 58.3 vs 28.5 ± 11.38 pg/mL, in NP and P colostrum fed calves, respectively). There were no differences in general biochemistry at 24-h samples, but P fed calves had greater serum levels of cholesterol, total proteins, and tended to have lower AST serum levels throughout the study. Although no effects on performance were demonstrated when feeding P or NP colostrum to calves, some blood biochemical changes were observed, which might affect calf development.

Key Words: calf, colostrum, cytokine