A comparison of two multivalent viral vaccine programs in feedlot calves at high risk of developing undifferentiated fever/bovine respiratory disease.

A field study was conducted to compare the relative effects of two multivalent viral vaccine programs on animal health, feedlot performance, and carcass characteristics of feedlot calves at high risk of developing undifferentiated fever/bovine respiratory disease (UF/BRD). Upon arrival at the feedlot, 3,264 animals were randomly allocated to one of two experimental groups: PYR5 (Pyramid® 5, Fort Dodge Animal Health, Division of Wyeth, Overland Park, Kansas) or EXP5 (Express® 5, Boehringer Ingelheim Vetmedica, Inc., St. Joseph, Missouri). All animals were re-vaccinated with their respective vaccines at 139 days-on-feed. The initial undifferentiated fever (UF) treatment rate was significantly (P<0.05) lower in the PYR5 group than in the EXP5 group (RR=0.70, 95% CI=0.53-0.93). On a live-weight basis, the dry matter-to-gain ratio (DM:G) was significantly (P<0.05) improved in the PYR5 group compared to the EXP5 group. Yield grades were improved in the PYR5 group, with a significantly (P<0.05) lower proportion of YG USDA 3 carcasses in the PYR5 group compared to the EXP5 group. No significant differences were detected in any other animal health, feedlot performance, or carcass characteristic variables between the experimental groups at the P<0.05 level. The economic analysis showed an advantage of $1.36 US per animal in the PYR5 group due to the lower initial UF treatment rate and proportion of YG USDA 3 carcasses.