Despite improvements made in the dairy industry and advances on heifer management, calf morbidity and mortality are still high. Calves rely on colostrum ingestion for acquisition of passive immunity, and provision of insufficient quantity of colostrum may lead these animals to failure of transfer passive immunity, hence leading to higher risks of morbidity and mortality. Many farms do not have sufficient colostrum available at times to feed their calves. Synthesis of colostrum starts few weeks before calving and it is at the time when cows are experiencing augmented metabolic adaptations due to increasing nutrient demands for fetal growth, colostrogenesis, and preparation for the onset of lactogenesis. The study described in Chapter 2 aimed to compare the metabolic status of dairy cows during the last 6 wk of gestation based on colostrum volume and Ig content across seasons during a year. The results in the latter study suggest that greater availability of antioxidants might support the production of higher volumes of colostrum. Therefore, the study reported in Chapter 3, aimed to evaluate whether administering a dietary antioxidant supplement during the last 3 weeks of gestation improves colostrum volume and immunoglobulin content. Our results showed that DATS increased colostrum volume. However, despite finding higher volume of colostrum in treatment group with statistical differences compared to control, the distribution of colostrum volume between groups are relatively the same, as well for IgG, IgM, and IgA.
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