title: [Reliability of bacteriological studies of composite samples in the diagnosis of subclinical udder infections in cattle].
abstract: This study evaluated the reliability of making bacteriological cultures of composite milk samples for the diagnosis of subclinical udder infections in dairy herds. Quarter samples as well as composite samples were collected from 482 cows with suspected subclinical mastitis from 69 Dutch dairy farms. The samples were used to measured somatic cell counts and to prepare bacteriological cultures. The sensitivity and specificity of the bacteriological cultures of the composite samples were compared with those of the quarter samples. The sensitivity of Staphylococcus aureus, Streptococcus uberis, Streptococcus agalactiae and Streptococcus dysgalactiae was 57.9%, 65.2%, 86.6%, and 60.3%, respectively. The specificity was higher than 98% for all four bacteria. Although information is lost when composite samples are used, composite samples are useful, especially for large dairy herds. The advantage and disadvantages of the use of composite samples are discussed.
authors.affiliation: Faculteit der Diergeneeskunde, Vakgroep Bedrijfsdiergeneeskunde en Voortplanting, Utrecht.
authors.forename: M L
authors.initials: ML
authors.lastname: Morselt
authors.forename: T J
authors.initials: TJ
authors.lastname: Lam
authors.forename: L A
authors.initials: LA
authors.lastname: van Wuijckhuise
authors.forename: P
authors.initials: P
authors.lastname: Franken
authors.forename: E G
authors.initials: EG
authors.lastname: Hartman
authors.forename: Y H
authors.initials: YH
authors.lastname: Schukken
mesh_terms: D000818:Animals; D001431:Bacteriological Techniques / Q000592:standards / Q000662:veterinary*; D002417:Cattle; D005260:Female; D008414:Mastitis, Bovine / Q000382:microbiology*; D008892:Milk / Q000382:microbiology*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000662:veterinary; D013211:Staphylococcus aureus / Q000254:growth & development; D013291:Streptococcus / Q000254:growth & development
vernacular_title: De betrouwbaarheid van het bacteriologisch onderzoek van mengmonsters voor de diagnose van subklinische uierinfecties bij rundvee.