Influence of clostridial vaccines and injection sites on performance, feeding behavior, and lesion size scores of beef steers

Several clostridial vaccines are currently being used in the beef cattle in dustry. Of greatest concern is altering the location and route of administr ation of these vaccines to reduce injection-site lesions while maintaining seroconversion. Two experiments were conducted to determine the effect of c lostridial vaccines and injection sites on the performance, feeding behavio r, and lesion size scores of beef steers. In Exp. 1, 80 crossbred beef stee rs (BW 237 +/- 3.2 kg) were allotted randomly into five groups and given 14 d to adapt to the feed and individual feed intake-monitoring devices (Pinp ointer devices) before starting the study. Each group was assigned randomly to one of the following vaccination treatments: 1) control (sterile saline water), 2) Alpha-7 Ear (A7E), 3) Alpha-7 Prescapula (A7P), 4) Vision-7: Pr escapula (V7P),; and 5) Ultrabac-7 Prescapula (U7P). All vaccines were inje cted s.c. in the ear or prescapular region, and injection sites were palpat ed on d 0 and 28 (Exp. I) and on d 63 and 91 (Exp. 2). The protocol for Exp . 2 was exactly the same as for Exp. 1 except treatments included control, A7P, Alpha-CD Ear (ACDE), Alpha-CD Preseapula (ACDP), Fortress-7 Prescapula (F7P), and V7P. Also, control and steers receiving F7P and V7P were revacc inated on d 63 and palpated on d 91. Results' of Exp, 1 indicate that the A 7E and U7P steers had a feed intake lower (P < 0.01) than all other treatme nt groups. The ADG of the A7P and A7E steers were not different (P > 0.05) from those of the control steers. The gain:feed ratio of the A7E steers was 41% higher (P < 0.01) than that of the V7P steers (Exp.1). The results of Exp. 2 indicated that the control, ACDP, and V7P steers had greater (p < 0. 01) ADG than all other treatment groups, but the gain:feed ratios were not different (P > 0.05) among all treatment groups. Lesion sizes differed by v accine and injection site in both experiments. These data suggest that vacc inating beef steers s.c. in the ear produced gain:feed ratios and lesion si ze scores that were similar to prescapular vaccinations. However, more rese arch is required to determine the immune response of vaccinating cattle in the ear.