Clinical and immunologic responses of vaccinated and unvaccinated calves to infection with a virulent type-II isolate of bovine viral diarrhea virus

Victor S. Cortese From the Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4 (Cortese, West, Hassard, Ellis); Pfizer Animal Health Group, 812 Springdale Dr, Exton, PA 19341-2803 (Cortese); and Animal Health Laboratory, Laboratory Services Division, University of Guelph, PO Box 3612, Guelph, Ontario, Canada N1H 6R8 (Carman).

Search for other papers by Victor S. Cortese in
Current site
Google Scholar
PubMed
Close
 DVM
,
Keith H. West From the Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4 (Cortese, West, Hassard, Ellis); Pfizer Animal Health Group, 812 Springdale Dr, Exton, PA 19341-2803 (Cortese); and Animal Health Laboratory, Laboratory Services Division, University of Guelph, PO Box 3612, Guelph, Ontario, Canada N1H 6R8 (Carman).

Search for other papers by Keith H. West in
Current site
Google Scholar
PubMed
Close
 DVM
,
Lori E. Hassard From the Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4 (Cortese, West, Hassard, Ellis); Pfizer Animal Health Group, 812 Springdale Dr, Exton, PA 19341-2803 (Cortese); and Animal Health Laboratory, Laboratory Services Division, University of Guelph, PO Box 3612, Guelph, Ontario, Canada N1H 6R8 (Carman).

Search for other papers by Lori E. Hassard in
Current site
Google Scholar
PubMed
Close
 BS
,
Suzanne Carman From the Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4 (Cortese, West, Hassard, Ellis); Pfizer Animal Health Group, 812 Springdale Dr, Exton, PA 19341-2803 (Cortese); and Animal Health Laboratory, Laboratory Services Division, University of Guelph, PO Box 3612, Guelph, Ontario, Canada N1H 6R8 (Carman).

Search for other papers by Suzanne Carman in
Current site
Google Scholar
PubMed
Close
 DVM, PhD
, and
John A. Ellis From the Department of Veterinary Microbiology, Western College of Veterinary Medicine, University of Saskatchewan, Saskatoon, Saskatchewan, Canada S7N 5B4 (Cortese, West, Hassard, Ellis); Pfizer Animal Health Group, 812 Springdale Dr, Exton, PA 19341-2803 (Cortese); and Animal Health Laboratory, Laboratory Services Division, University of Guelph, PO Box 3612, Guelph, Ontario, Canada N1H 6R8 (Carman).

Search for other papers by John A. Ellis in
Current site
Google Scholar
PubMed
Close
 DVM, PhD

Click on author name to view affiliation information

Objective

To determine efficacy of a modified-live type-I isolate of bovine viral diarrhea virus (BVDV) vaccine in protecting calves from infection with a virulent type-II isolate, and to determine which type of immune response (ie, humoral or cellular) correlates with protection.

Design

Prospective study.

Animals

28 neonatal Holstein and Holstein-cross calves.

Procedure

Within 18 hours of birth, calves received maternal colostrum or were fed pooled colostrum. On days 7 to 10 after birth, calves were determined to be seropositive (n = 16) or seronegative (12) for antibodies to BVDV on the basis of ELISA and virus neutralization test results. Seropositive and seronegative 10- to 14-day-old calves were then given a combined vaccine that contained a modified-live type-I isolate of BVDV or a similar vaccine that lacked protection against bovine viral diarrhea. All calves were inoculated intranasally approximately 21 days after vaccination with a virulent type-II isolate of BVDV. Clinical and immunologic variables, including clinical scores, rectal temperatures, results of CBC with lymphocyte subset analysis, antibody responses, and cell-mediated immune responses, were monitored for 14 days after inoculation.

Results

Seronegative-unvaccinated calves developed severe disease and required euthanasia. Vaccination of seronegative calves with a modified-live type-I isolate had a disease-sparing effect as did passive transfer of colostral antibodies to BVDV. Clinical scores were not significantly different between seropositive-vaccinated and seropositive-unvaccinated calves after viral inoculation.

Clinical Implications

A single dose of a modified-live type-I isolate of BVDV vaccine protects young calves from clinical signs of disease associated with type-II isolates. (J Am Vet Med Assoc 1998;213:1312-1319)

Objective

To determine efficacy of a modified-live type-I isolate of bovine viral diarrhea virus (BVDV) vaccine in protecting calves from infection with a virulent type-II isolate, and to determine which type of immune response (ie, humoral or cellular) correlates with protection.

Design

Prospective study.

Animals

28 neonatal Holstein and Holstein-cross calves.

Procedure

Within 18 hours of birth, calves received maternal colostrum or were fed pooled colostrum. On days 7 to 10 after birth, calves were determined to be seropositive (n = 16) or seronegative (12) for antibodies to BVDV on the basis of ELISA and virus neutralization test results. Seropositive and seronegative 10- to 14-day-old calves were then given a combined vaccine that contained a modified-live type-I isolate of BVDV or a similar vaccine that lacked protection against bovine viral diarrhea. All calves were inoculated intranasally approximately 21 days after vaccination with a virulent type-II isolate of BVDV. Clinical and immunologic variables, including clinical scores, rectal temperatures, results of CBC with lymphocyte subset analysis, antibody responses, and cell-mediated immune responses, were monitored for 14 days after inoculation.

Results

Seronegative-unvaccinated calves developed severe disease and required euthanasia. Vaccination of seronegative calves with a modified-live type-I isolate had a disease-sparing effect as did passive transfer of colostral antibodies to BVDV. Clinical scores were not significantly different between seropositive-vaccinated and seropositive-unvaccinated calves after viral inoculation.

Clinical Implications

A single dose of a modified-live type-I isolate of BVDV vaccine protects young calves from clinical signs of disease associated with type-II isolates. (J Am Vet Med Assoc 1998;213:1312-1319)

All Time Past Year Past 30 Days
Abstract Views 0 0 0
Full Text Views 341 341 130
PDF Downloads 25 25 2
Advertisement