title: Relationships between demographic variables and lead toxicosis in cattle evaluated at North American veterinary teaching hospitals.
abstract: OBJECTIVE
  To determine associations between age, sex, breed, and month and year of admission and the diagnosis of lead toxicosis in cattle.
  
  
  METHODS
  Retrospective case-control study. Sample Population-Records of all cattle evaluated at North American veterinary teaching hospitals during the years 1963 to 2002, which were available through the Veterinary Medical Database.
  
  
  METHODS
  Logistic regression was used to evaluate the associations between postulated risk factors and the occurrence of lead toxicosis in cattle and predict the occurrence of the diagnosis of lead toxicosis in cattle.
  
  
  RESULTS
  413 cases of lead intoxication and 202,363 control cattle were identified and met the inclusion criteria. Cattle < 4 years of age were at increased risk for the diagnosis of lead intoxication relative to cattle > or = 4 years of age. Cattle > or = 2 months and < 6 months of age had the greatest risk for lead intoxication (odds ratio, 12.3). Angus cattle were at greater risk for toxicosis (odds ratio, 1.95), compared with other breeds. The risk of lead toxicosis was greater before 1985 (odds ratio, 1.94) than the risk thereafter. The risk of lead toxicosis diagnosis was greatest in the months of May, June, July, and August.
  
  
  CONCLUSIONS
  Lead toxicosis in cattle was associated with age < 4 years and the Angus breed. A seasonal pattern existed with peak occurrence in the late spring and summer. The occurrence of lead toxicosis has declined over time.
authors.affiliation: Department of Veterinary Medicine and Surgery, College of Veterinary Medicine, University of Missouri, Columbia, MO 65211, USA.
authors.forename: Vengai
authors.initials: V
authors.lastname: Mavangira
authors.forename: Tim J
authors.initials: TJ
authors.lastname: Evans
authors.forename: J Armando
authors.initials: JA
authors.lastname: Villamil
authors.forename: Allen W
authors.initials: AW
authors.lastname: Hahn
authors.forename: Munashe
authors.initials: M
authors.lastname: Chigerwe
authors.forename: Jeff W
authors.initials: JW
authors.lastname: Tyler
mesh_terms: D000367:Age Factors; D000818:Animals; D001947:Breeding; D016022:Case-Control Studies; D002417:Cattle; D002418:Cattle Diseases / Q000175:diagnosis* / Q000453:epidemiology*; D016001:Confidence Intervals; D003710:Demography; D005260:Female; D007855:Lead Poisoning / Q000175:diagnosis / Q000453:epidemiology / Q000662:veterinary*; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D011996:Records / Q000662:veterinary; D012189:Retrospective Studies; D012307:Risk Factors; D012621:Seasons; D012737:Sex Factors; D014481:United States / Q000453:epidemiology