title: Survey of management practices related to bovine respiratory disease in preweaned calves on California dairies.
abstract: In the spring of 2013, a survey of California (CA) dairies was performed to characterize management practices related to bovine respiratory disease in preweaned calves, compare these practices across geographic regions of the state, and determine the principal components that explain the variability in management between herds. The questionnaire consisted of 53 questions divided into 6 sections to assess management practices affecting dairy calves from precalving to weaning. The questionnaire was mailed to 1,523 grade A licensed dairies in CA and 224 responses (14.7%) were collected. Survey response rates were similar over the 3 defined regions of CA: northern CA, northern San Joaquin Valley, and the greater southern CA region. The mean size of respondent herds was 1,423 milking cows. Most dairies reported raising preweaned calves on-site (59.7%). In 93.3% of dairies, preweaned calves were raised in some form of individual housing. Nonsaleable milk was the most frequent liquid diet fed to preweaned heifers (75.2%). Several important differences were identified between calf-raising practices in CA and practices reported in recent nationwide studies, including herd sizes, housing practices, and sources of milk fed to heifers. The differences between the CA and nationwide studies may be explained by differences in herd size. Regional differences within CA were also identified. Compared with the 2 other regions, northern CA dairies were found to have smaller herds, less Holstein cattle, calves remained with dams for longer periods of time after calving, were more likely to be certified organic dairies, and raised their own calves more often. Principal component analysis was performed and identified 11 components composed of 28 variables (questions) that explained 66.5% of the variability in the data. The identified components and questions will contribute to developing a risk assessment tool for bovine respiratory disease in preweaned dairy calves.
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, Davis, Tulare 93274.
authors.forename: W J
authors.initials: WJ
authors.lastname: Love
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, Davis, Tulare 93274; Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis 95616.
authors.forename: T W
authors.initials: TW
authors.lastname: Lehenbauer
authors.affiliation: Cooperative Extension, Division of Agriculture and Natural Resources, University of California, Orland, 95963.
authors.forename: B M
authors.initials: BM
authors.lastname: Karle
authors.affiliation: Department of Animal Sciences and Industry, Kansas State University, Manhattan 66506.
authors.forename: Lindsey E
authors.initials: LE
authors.lastname: Hulbert
authors.affiliation: Animal Health and Food Safety Services, California Department of Food and Agriculture, Modesto 95358.
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Anderson
authors.affiliation: Department of Animal Science, University of California, Davis 95616.
authors.forename: A L
authors.initials: AL
authors.lastname: Van Eenennaam
authors.affiliation: Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis 95616.
authors.forename: T B
authors.initials: TB
authors.lastname: Farver
authors.affiliation: Veterinary Medicine Teaching and Research Center, School of Veterinary Medicine, University of California, Davis, Tulare 93274; Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis 95616. Electronic address: saly@ucdavis.edu.
authors.forename: S S
authors.initials: SS
authors.lastname: Aly
mesh_terms: D000827:Animal Welfare; D000818:Animals; D000831:Animals, Newborn; D002140:California / Q000453:epidemiology; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology*; D003612:Dairying / Q000379:methods*; D004032:Diet / Q000662:veterinary; D005260:Female; D008892:Milk / Q000378:metabolism*; D012140:Respiratory Tract Diseases / Q000453:epidemiology / Q000662:veterinary*; D018570:Risk Assessment; D011795:Surveys and Questionnaires; D014886:Weaning
keywords: California dairies; bovine respiratory disease; dairy calves; preweaning