title: Prevalence and distribution of mastitis pathogens in subclinically infected dairy cows in Flanders, Belgium.
abstract: The main objective was to determine the prevalence of intramammary infections (IMI) in dairy cows in Flanders, Belgium. Data were obtained from quarter milk samples of dairy herds subjected to a mandatory yearly screening of all lactating cows. A total of 178,668 quarter milk samples were collected at 1087 cross-sectional dairy herd screenings performed in three consecutive years. Of the dairy cows, 40% had at least one culture-positive quarter. More than 50% of all IMI were caused by non-aureus staphylococci. Streptococcus agalactiae is almost eradicated in Flanders, whereas Staphylococcus aureus was isolated from 18% of the culture-positive quarters. In addition, the distribution of mastitis pathogens in quarter milk samples from selected dairy cows with an elevated somatic cell count (SCC) is described. From 6390 cows with a geometric mean composite SCC 250,000 cells/ml, nearly 65% had at least one culture-positive quarter. The majority of the IMI were caused by non-aureus staphylococci (41.1%), whereas Staph. aureus and aesculin-positive cocci were found in respectively 25% and 18% of the culture-positive milk samples. We conclude that more efforts are needed in the prevention and control of subclinical mastitis in Flanders. Non-aureus staphylococci are the predominant cause of IMI, warranting more research regarding the epidemiology and pathogenicity of those species.
authors.affiliation: Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium. Sofie.Piepers@UGent.be
authors.forename: Sofie
authors.initials: S
authors.lastname: Piepers
authors.forename: Luc
authors.initials: L
authors.lastname: De Meulemeester
authors.forename: Aart
authors.initials: A
authors.lastname: de Kruif
authors.forename: Geert
authors.initials: G
authors.lastname: Opsomer
authors.forename: Herman W
authors.initials: HW
authors.lastname: Barkema
authors.forename: Sarne
authors.initials: S
authors.lastname: De Vliegher
mesh_terms: D000818:Animals; D001424:Bacterial Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D001530:Belgium / Q000453:epidemiology; D002417:Cattle; D005260:Female; D008414:Mastitis, Bovine / Q000453:epidemiology / Q000382:microbiology*; D015995:Prevalence