title: Diversity of Salmonella serotypes in cull (market) dairy cows at slaughter.
abstract: OBJECTIVE
  To determine the diversity of Salmonella serotypes isolated from a large population of cull (market) dairy cows at slaughter.
  
  
  METHODS
  Cross-sectional study.
  
  
  METHODS
  Salmonella organisms isolated from the cecal-colon contents of 5,087 market dairy cows.
  
  
  METHODS
  During winter and summer 1996, cecal-colon contents of cull dairy cows at slaughter were obtained from 5 US slaughter establishments. Specimens were subjected to microbiologic culturing for Salmonella spp at 1 laboratory. Identified isolates were compared with Salmonella isolation lists published by the Centers for Disease Control and Prevention (CDC) and the National Veterinary Services Laboratory (NVSL) for approximately the same period. The Simpson diversity index was used to calculate the likelihood that Salmonella isolates selected randomly by establishment were different.
  
  
  RESULTS
  Of 58 Salmonella serotypes identified, Salmonella ser. Montevideo was the most prevalent. Two of the top 10 CDC serotypes identified from in 1996, Salmonella ser. Typhimurium and S Montevideo, appeared on our top 10 list; 8 of the top 10 were found on NVSL listings. Thirty-one of 59 S. Typhimurium isolates were identified as DT104 and found at a west slaughter establishment, 30 during the winter and 1 during the summer. The greatest diversity of serotypes was at a southeast establishment during the summer; the least diversity was at a central establishment in the winter.
  
  
  CONCLUSIONS
  58 Salmonella serotypes were isolated from market dairy cows at slaughter and could pose a threat for food-borne illness. Salmonella Montevideo was the most frequently isolated serotype and may contribute substantially to salmonellosis in dairy cattle.
authors.affiliation: Food Animal Health and Management Center, College of Veterinary Medicine, Kansas State University, Manhattan 66506, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Galland
authors.forename: H F
authors.initials: HF
authors.lastname: Troutt
authors.forename: R L
authors.initials: RL
authors.lastname: Brewer
authors.forename: B I
authors.initials: BI
authors.lastname: Osburn
authors.forename: R K
authors.initials: RK
authors.lastname: Braun
authors.forename: P
authors.initials: P
authors.lastname: Sears
authors.forename: J A
authors.initials: JA
authors.lastname: Schmitz
authors.forename: A B
authors.initials: AB
authors.lastname: Childers
authors.forename: E
authors.initials: E
authors.lastname: Richey
authors.forename: K
authors.initials: K
authors.lastname: Murthy
authors.forename: E
authors.initials: E
authors.lastname: Mather
authors.forename: M
authors.initials: M
authors.lastname: Gibson
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000382:microbiology*; D002432:Cecum / Q000382:microbiology; D003106:Colon / Q000382:microbiology; D003430:Cross-Sectional Studies; D005260:Female; D005516:Food Microbiology; D011634:Public Health / Q000706:statistics & numerical data; D012475:Salmonella / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012621:Seasons; D012703:Serotyping / Q000662:veterinary; D014481:United States