title: The effect of bovine viral diarrhea virus infections on health and performance of feedlot cattle.
abstract: The aim of this study was to investigate the effect of bovine viral diarrhea virus (BVDV) infections (unapparent acute infections and persistent infections) on the overall health and performance of feedlot cattle. Calves from 25 pens (7132 calves) were enrolled in the study. Overall and infectious disease mortality rates were significantly higher (P < 0.05) in pens categorized at arrival as positive for type I BVDV and lower in pens that were positive for type II BVDV than in negative pens. Mortality attributed to BVDV infection or enteritis was significantly more common (P < 0.05) in the pens containing persistently infected (PI) calves than in pens not containing PI calves (non-PI pens). There were no statistically detectable (P > or = 0.05) differences in morbidity, overall mortality, average daily gain, or the dry matter intake to gain ratio between PI and non-PI pens. Although type-I BVDV infections in feedlots appear to contribute to higher mortality rates, the presence of PI calves alone does not appear to have a strong impact on pen-level animal health and feedlot performance.
authors.affiliation: Feedlot Health Management Services, P.O. Box 140, Okotoks, Alberta. calvinb@feedlothealth.com
authors.forename: Calvin W
authors.initials: CW
authors.lastname: Booker
authors.forename: Sameeh M
authors.initials: SM
authors.lastname: Abutarbush
authors.forename: Paul S
authors.initials: PS
authors.lastname: Morley
authors.forename: P Timothy
authors.initials: PT
authors.lastname: Guichon
authors.forename: Brian K
authors.initials: BK
authors.lastname: Wildman
authors.forename: G Kee
authors.initials: GK
authors.lastname: Jim
authors.forename: Oliver C
authors.initials: OC
authors.lastname: Schunicht
authors.forename: Tom J
authors.initials: TJ
authors.lastname: Pittman
authors.forename: Tye
authors.initials: T
authors.lastname: Perrett
authors.forename: John A
authors.initials: JA
authors.lastname: Ellis
authors.forename: Greg
authors.initials: G
authors.lastname: Appleyard
authors.forename: Deborah M
authors.initials: DM
authors.lastname: Haines
mesh_terms: D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D000831:Animals, Newborn; D001912:Bovine Virus Diarrhea-Mucosal Disease / Q000150:complications / Q000401:mortality / Q000473:pathology / Q000635:transmission; D002417:Cattle; D002908:Chronic Disease; D030241:Diarrhea Virus 1, Bovine Viral / Q000472:pathogenicity*; D030242:Diarrhea Virus 2, Bovine Viral / Q000472:pathogenicity*; D002149:Energy Intake; D006799:Housing, Animal; D008137:Longitudinal Studies; D008297:Male; D009017:Morbidity; D011446:Prospective Studies; D011897:Random Allocation; D014774:Virulence; D015430:Weight Gain