Serological responses to IBR viral vaccine and Mannheimia haemolytica bacterin/leukotoxoid administered with needle-free injection technology

摘要

Yearling steers were randomized to treatmentand vaccinated with 5-way modified liveviral vaccine and Mannheimia haemolyticabacterin/toxoid by using either needle-free or standard needle injection. Blood samples were collected from all animals at the time of vaccination and 21 days later, and the serum was analyzed for antibody titers to infectious bovine rhinotracheitis (IBR) virus and M. haemolytica leukotoxoid. Serological responses to the IBR viral fraction of the 5-way viral vaccine were significantly greater on day 21 after administration with the needle-freeinjection system. Serological responses to the M. haemolytica leukotoxoid tended to begreater on day 21 after administration with the needle-free injection system.