title: Effects of various vaccination protocols on passive and active immunity to Pasteurella haemolytica and Haemophilus somnus in beef calves.
abstract: Two field trials were conducted in a beef cow herd in Saskatchewan to determine the effectiveness of a combined Pasteurella haemolytica and Haemophilus somnus vaccine in increasing passively and actively acquired antibodies in beef calves. Vaccination of dams at 4 and/or 7 weeks prepartum was associated with increased antibody titers to P. haemolytica and H. somnus in their serum (P < 0.05), colostrum(P < 0.05), and serum of their calves at 3 days and 1 month of age (P < 0.05). There was no significant(P > 0.05) difference in antibody titers in the colostrum and serum of calves from single or double vaccinated dams. Calves vaccinated at 1 and 2 months of age in the face of maternal antibodies toP. haemolytica and H. somnus had significantly(P < 0.05) higher antibodies to P. haemolytica and H. somnus at 4 and 6 months of age than did unvaccinated calves. Calves vaccinated at 3 and 4 months of age in the face of low levels of preexisting antibodies had significantly (P < 0.05) higher antibodies toP. haemolytica at 5 months of age and to H. somnus at 5 and 6 months of age than did unvaccinated calves. Calves vaccinated once at 4 months of age had significantly(P < 0.05) higher antibody titers toP. haemolytica and H. somnus at 4.5 months of age than did unvaccinated calves, but this difference was not apparent at 6 months of age. These results suggest that vaccination of beef cows with a combined Pasteurella haemolytica and Haemophilus somnus vaccine once at 4 weeks prepartum will significantly (P < 0.05) increase passive antibody titers toP. haemolytica and H. somnus in their calves. Double vaccination of calves with preexisting maternal antibodies at 1 and 2 months of age will increase antibody titers to P. haemolytica and H. somnus until 6 months of age. Vaccination of beef calves with low levels of preexisting antibody at 3 and 4 months of age will increase antibody titers to H. somnus until 6 months of age and to P. haemolytica until 5 months of age.However, the level of antibodies achieved by vaccination may depend on the calves being studied, the level of preexisting antibodies, and the efficiency of passive transfer.
authors.affiliation: Veterinary Infectious Disease Organization, Saskatoon, Saskatchewan.
authors.forename: J
authors.initials: J
authors.lastname: Van Donkersgoed
authors.forename: C
authors.initials: C
authors.lastname: Guenther
authors.forename: B N
authors.initials: BN
authors.lastname: Evans
authors.forename: A A
authors.initials: AA
authors.lastname: Potter
authors.forename: R J
authors.initials: RJ
authors.lastname: Harland
mesh_terms: D000818:Animals; D000831:Animals, Newborn / Q000276:immunology; D000907:Antibodies, Bacterial / Q000032:analysis; D001428:Bacterial Vaccines / Q000008:administration & dosage / Q000276:immunology; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000517:prevention & control*; D003126:Colostrum / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay / Q000662:veterinary; D005260:Female; D006190:Haemophilus / Q000276:immunology*; D006192:Haemophilus Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D007110:Immunity, Active; D007112:Immunity, Maternally-Acquired; D007273:Injections, Intramuscular / Q000662:veterinary; D016978:Mannheimia haemolytica / Q000276:immunology*; D010326:Pasteurella Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D018410:Pneumonia, Bacterial / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary; D011247:Pregnancy; D014611:Vaccination / Q000379:methods / Q000662:veterinary; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000907:Antibodies, Bacterial; D001428:Bacterial Vaccines; D014614:Vaccines, Synthetic