Efficacy Evaluation of a New Vaccine Against Bovine Mastitis: Field Trial Results

摘要

The objective of the present study was to evaluate the efficacy of a new vaccine against bovine mastitis in a field trial.The field trial was conducted following Good Clinical Practices (GCP) (VICH) and was multicentric, randomized, double blind, controlled (with a parallel negative control group) and stratified (primiparous and multiparous). The vaccine used was STARTVAC~R(HIPRA), containing inactivated Escherichia coli J5 and inactivated Staphylococcus aureus SP140 strain expressing Slime Associated Antigenic Complex (SAAC). A total of 386 gestating cows (198 vaccinated and 188 inoculated with a placebo) were used in accordance with the proposed vaccine schedule: the 1st injection was applied 45 days before the expected calving date, the 2nd injection 35 days thereafter and the 3rd injection 62 days after the 2nd injection by intramuscular route. Incidence of clinicalmastitis (evaluating general and local symptoms), subclinical mastitis, weekly sampling of milk by quarters with microbiological analysis and SCC, daily milk production and mastitis treatments with pharmacological products were recorded throughout the entire observation period (130 days post-partum). Logistic regression analysis and the Chi-square test were used for statistical evaluation.