Effect of trivalent modified-live virus respiratory vaccine on performance, health, and carcass traits of lightweight feeder steers

Abstract

A total of 3,615 lightweight feeder steers were used to compare the effects of trivalent (infectious bovine rhinotracheitis virus and bovine viral diarrhea virus types 1 and 2) modified-live virus (MLV) vaccine products on performance, health, and carcass traits of cattle in a commercial feedlot setting. The three trivalent MLV vaccination products compared were Express? 3 (Boeh-ringer Ingelheim Vetmedica, Inc., St. Joseph MO), Bovi-Shield GOLD? IBR-BVD (Pfizer Animal Health, New York, NY), and Vista? 3 SQ (Intervet/Schering-Plough Animal Health, Summit, NJ). No differences (P?0.30) in feed conversion, final weight, or gain performance were detected among vaccination treatments. The percentage of BRD morbidity was similar (P=0.15) among treatments, averaging 12.3% overall. Furthermore, no vaccine treatment differences (P?0.36) were observed for relapse percentage, mortality or railer incidence, regardless of cause. All cattle used in the study were tested for persistent infection (PI) with BVDV, and the prevalence of cattle testing positive for PI-BVDV was similar (P=0.56) among the vaccine treatments and averaged 0.27% overall. Cattle which tested positive for PI-BVDV were not removed from the study pens, and after data were pooled, health and performance did not differ for pens with or without a PI-BVDV pen mate. When utilizing lightweight feeder steers with relatively low BRD-associated morbidity and mortality, there was no difference in performance, health, and carcass trait observations among the three trivalent MLV vaccine products evaluated.