Future work could also examine the effectiveness of heterologous BVDV vaccination in the control of acute BVD infections in recently weaned beef calves. Acknowledgments The authors acknowledge support from the Saskatchewan Agricultural Development Fund, Saskatchewan Cattlemens Association, and the University of Saskatchewan. had significantly higher BRSV-specific antibody concentrations after boosting compared with the 2 2 homologous groups. No differences in BHV-specific antibody concentrations were observed Acadesine (Aicar,NSC 105823) between any Acadesine (Aicar,NSC 105823) of the groups. Rsum valuation des rponses spcifiques en anticorps contre le computer virus respiratoire syncitial bovin (BRSV) et lherpsvirus bovin (BHV) chez des bovins dembouche de lOuest canadien vaccins en primo-vaccination et en rappel de manire homologue ou htrologue. Les maladies respiratoires bovines (BRD) sont une cause conomiquement importante de morbidit et de Acadesine (Aicar,NSC 105823) mortalit chez les veaux dembouche. La maitrise des BRD fait appel le plus souvent une vaccination ? homologue ? utilisant le mme vaccin injectable de computer virus vivant modifi (MLV) pour la primo-vaccination et le rappel. La primo-vaccination et le rappel htrologue utilisent diffrentes voies et formes antigniques pour lamor?age et le rappel. Trois protocoles de vaccination furent compars : un groupe MLV injectable (IJ) (IJ-MLV) (amor?age avec IJ-MLV environ 48 jours et rappel avec IJ-MLV au sevrage). Un groupe MLV intranasal (IN) (IN-MLV) (amor?age intranasal avec MLV environ 24 heures, deux rappels avec IJ-MLV), et un groupe avec un vaccin intranasal de computer virus tu (IN-KV) (amor?age avec IN-MLV environ 24 heures, deux rappels avec IJ-KV). Les concentrations danticorps sriques dtermines par preuves immuno-enzymatiques (ELISAs) furent compares et le groupe IN-KV avait des concentrations danticorps spcifiques contre BRSV significativement plus leves aprs le rappel comparativement Acadesine (Aicar,NSC 105823) aux deux groups homologues. Aucune diffrence dans les concentrations danticorps spcifiques contre le BHV ne furent observes entre les groupes. (Traduit par Dr Serge Messier) Introduction Veterinarians and suppliers vaccinate calves to primary their immune systems against pathogens associated with bovine respiratory disease (BRD) and as one method to manage the impact of the disease. Commonly used viral vaccines contain modified-live viruses (MLV) including bovine respiratory syncytial computer virus (BRSV), bovine herpes virus type 1 (BHV1), bovine parainfluenza computer virus 3 (BPIV3), and bovine viral diarrhea computer virus types 1 and 2 (BVDV1 and 2) (1). Bovine respiratory syncytial computer virus, BHV1, and BPIV3 target respiratory epithelia and are directly associated with respiratory disease development. Bovine viral diarrhea computer virus types 1 and 2 are included in the vaccines due to the virus ability to suppress the animals immune system (2). Attesting to the validity of this approach, a recent meta-analysis of the impact of vaccination on feedlot calf BRD morbidity and mortality indicated that vaccinating for viral pathogens resulted in a protective effect, reducing both morbidity and mortality (3). However, despite the adoption of routine vaccination, BRD still has a unfavorable economic impact on cattle feeding operations across North America through calf morbidity and mortality, and production losses (1,4). The less than optimal effectiveness of vaccination in commercial settings may in part be due to how vaccines are applied, including factors such as vaccination in the face of maternal antibodies (IFOMA) and at the time of stress associated with weaning. Improper application is usually partly due to timing of the priming dose of vaccine; most suppliers vaccinate neonatal Rabbit Polyclonal to HTR2B calves when it is convenient to handle cattle at spring turnout, when the calves are approximately 2 mo aged (5). Administration of injectable immunogens to calves is one of the most common methods of vaccination in cow-calf operations; initial priming being the intention (5). The priming vaccine dose is frequently applied when calves are ~2 mo of age, followed by a booster at ~6 mo of age (5). However, at 2 mo of age calves with good passive transfer will still have high maternal antibody concentrations (6), and maternal antibodies can interfere with the immune systems ability to respond to a parenterally administered vaccine (7C9). Determining a specific time to vaccinate is usually difficult, as maternal antibody concentrations decrease at different rates depending on a variety of factors, most notably the level of passive transfer of maternal antibodies (MatAb) (6,8,10). Mucosal vaccination can stimulate an immune response in the face of MatAb, Acadesine (Aicar,NSC 105823) effectively bypassing this inhibitory effect (11). Moreover, mucosal vaccination can also primary for systemic immunity (12,13). Another possible challenge to vaccine effectiveness may be that most vaccine protocols utilize a homologous approach (5); priming and boosting with either the same type of antigen, or.