Evaluation of fetal protection against experimental infection with type 1 and type 2 bovine viral diarrhea virus after vaccination of the dam with a bivalent modified-live virus vaccine.
OBJECTIVE
To evaluate the efficacy of a modified-live virus (MLV) combination vaccine containing type 1 and type 2 bovine viral diarrhea virus (BVDV) in providing fetal protection against challenge with heterologous type 1 and type 2 BVDV.


METHODS
Prospective study.


METHODS
55 heifers.


METHODS
Heifers were vaccinated with a commercial MLV combination vaccine or given a sham vaccine (sterile water) and bred 47 to 53 days later. Heifers were challenged with type 1 or type 2 BVDV on days 75 to 79 of gestation. Clinical signs of BVDV infection, presence of viremia, and WBC count were assessed for 14 days after challenge. Fetuses were collected on days 152 to 156 of gestation, and virus isolation was attempted from fetal tissues.


RESULTS
Type 1 BVDV was not isolated in any fetuses from vaccinated heifers and was isolated in all fetuses from nonvaccinated heifers challenged with type 1 BVDV. Type 2 BVDV was isolated in 1 fetus from a vaccinated heifer and all fetuses from nonvaccinated heifers challenged with type 2 BVDV.


CONCLUSIONS
A commercial MLV combination vaccine containing type 1 and type 2 BVDV given to the dam prior to breeding protected 100% of fetuses against type 1 BVDV infection and 95% of fetuses against type 2 BVDV infection. Use of a bivalent MLV vaccine in combination with a comprehensive BVDV control program should result in decreased incidence of persistent infection in calves and therefore minimize the risk of BVDV infection in the herd.
Fairbanks
Kris K
KK
Rural Technologies Incorporated, 1008 32nd Ave, Brookings, SD 57006, USA.
Rinehart
Carol L
CL
Ohnesorge
Wm Charles
WC
Loughin
Marie M
MM
Chase
Christopher C L
CC
D000034:Abortion, Veterinary / Q000517:prevention & control* / Q000821:virology; D000818:Animals; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000517:prevention & control* / Q000821:virology; D002417:Cattle; D030241:Diarrhea Virus 1, Bovine Viral / Q000276:immunology* / Q000302:isolation & purification; D030242:Diarrhea Virus 2, Bovine Viral / Q000276:immunology* / Q000302:isolation & purification; D005260:Female; D005315:Fetal Diseases / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control / Q000662:veterinary; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000517:prevention & control / Q000662:veterinary; D011446:Prospective Studies; D016896:Treatment Outcome; D014613:Vaccines, Attenuated; D017778:Vaccines, Combined / Q000008:administration & dosage / Q000276:immunology*; D014765:Viral Vaccines; D014766:Viremia / Q000453:epidemiology / Q000517:prevention & control / Q000662:veterinary
D014613:Vaccines, Attenuated; D017778:Vaccines, Combined; D014765:Viral Vaccines