Early immunization of newborn calves involved in viral agents for bovine respiratory disease complex

Abstract

The objective of this research is to investigate the mechanisms of humoral and cellular immune response after immunization of premature newborn calves, using as medel the bovine viral diarrhea virus (BVDV), bovine herpesvirus (BoHV-1) and bovine respiratory syncytial virus (BRSV). Therefore, mothers are immunized with inactivated vaccine for these diseases in pre-calving and separated from their calves immediately after birth. The calves (n = 10) will be primed with the same vaccine used in cows to 14 days after birth (pn), and revaccinated 30 days after (Group 1). Group 2 (n = 10) will be composed of non-vaccinated calves for the evaluation of colostral immunity. Blood samples will be collected from calves prior to first vaccination (TO), before revaccination (T1) and 30 days after revaccination (T2). The Brazilian team will evaluate the humoral response imune by measurement of ACs for BVDV and BoHV by means of serum neutralization (SN). The cellular response will be assessed by immunophenotyping and activation of T cells, in addition, will be held cultivation of mononuclear cells from the blood stimulated with inactivated BoHV for measuring the cytokines IL-10 and interferon-gamma (IFN -V), respectively. The Argentine team will carry out the measurement of ACs for BRSV; cultivation of mononuclear leukocytes from the blood, assessing their proliferative response upon stimulation with BRSW, and determing the gene expression of IL-10 and IFN-y by the RT-PCR technique. (AU)