Clostridial antibody response from injection-site lesions in beef cattle, long-term response to single or multiple doses, and response in newborn beef calves

Experiments were conducted to compare clostridial antibody response of beef heifers that do and do not develop injection-site lesions, evaluate long-t erm antibody response of a single- and multiple-dose toxoid, and evaluate t he ability of a clostridial toxoid to elicit an active antibody response in newborn calves. In Exp. 1, 37 weaned heifers were vaccinated (d 0) with a clostridial vaccine (Alpha-7, 2 mL, s.c.). Serum samples were collected on d 0, 28, 56, 84, and 112 to determine clostridial antibody titers. On d 28, heifers were visually inspected and palpated for injection-site lesions. T he percentage of heifers that developed lesions was 64.9%. Lesioned heifers had elevated antibody titers for Clostridium chauvoei (CC) on d 28 (P < 0. 08) and 84 (P < 0.07) compared with non-lesioned heifers. Clostridium sorde llii (CS) and perfringens type D (CPD) antibody titers were greater in lesi oned heifers than in non-lesioned heifers on d 28 and 56. In Exp. 2, long-t erm antibody response of Alpha-7 (A7) and Ultrabac 7 (UB7) was investigated in stocker heifers. The A7 heifers (n = 15) received one 2-mL vaccination (d 0), and the UB7 heifers (n = 15) received a 5-mL vaccination on d 0 and 28. Blood samples were collected on d 0, 28, 56, 84, 112, 140, and 180. Clo stridium chauvoei, CPD, and Cl. novyi (CN) antibody titers from the A7 heif ers were greater than those from the UB7 heifers on d 28. Due to the second UB7 injection, CC, CS, CN, and Cl. perfringens type C (CPC) antibody titer s were greater in UB7 heifers than in A7 heifers on d 56. By d 112, titers were not different, and by d 140 all antibody titers were below detectable levels. In Exp. 3, 58 pregnant, mature, crossbred cows were vaccinated with A7 before calving. At birth, calves were carefully observed to ensure cons umption of colostrum. Calves were blocked according to parturition date, an d calves in each block were randomly allocated to receive A7 (s.c. at 3 3 d of age) or remain unvaccinated controls. Calves were bled at the time of v accination (d 0) and on d 28, 56, 84, and 112. Antibody titers for CC, CPC, and CPD were elevated on d 0 and decreased throughout the experimental per iod (P < 0.01), but no titer differences (P > 0.10) were detected between t reatment groups on any of the days sampled. These data indicated that antib ody titers against clostridial diseases are enhanced when injection-site le sions develop. One injection of Alpha-7 seemed to provide the same length o f protection as two injections of Ultrabac 7.