title: Controlling highly prevalent Staphylococcus aureus mastitis from the dairy farm.
abstract: In 57 Holstein cows where the dairy farm uses a milking parlor system, the somatic cell count (SCC) increased persistently in the bulk milk (monthly mean 52.3 x 10(4) cells/ml; range 21 to 94 x 10(4) cells/ml). We detected S. aureus in 24 (41.2%) of the 54 lactating cows and in 29 (12.8%) of 227 quarters of the 57 milking cows in the herd. A control program was implemented in an effort to eradicate S. aureus mastitis from this dairy farm. The control plan established improved handling of the lactating cows, improved milking procedures, dry-cow therapy, and culling of infected cows. The program was monitored for 3.5 years by frequent checkups on the rate of S. aureus infection, the SCC, and the changes in milk composition. Eighteen months after the control program was started, the rate of S. aureus infection in the quarter milk decreased dramatically, and no S. aureus isolates were found in the milk of the remaining cows. The SCC in the bulk milk of the herd dropped to a monthly mean of <20 x 10(4) cells/ml. In conclusion, the control program was effective for controlling persistent S. aureus mastitis in this dairy herd.
authors.affiliation: Department of Animal Health, School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu, Hokkaido 069-8501, Japan. nagahata@rakuno.ac.jp
authors.forename: Hajime
authors.initials: H
authors.lastname: Nagahata
authors.forename: Hiroyasu
authors.initials: H
authors.lastname: Ito
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Maruta
authors.forename: Yuzo
authors.initials: Y
authors.lastname: Nishikawa
authors.forename: Hiromi
authors.initials: H
authors.lastname: Susukino
authors.forename: Susumu
authors.initials: S
authors.lastname: Matsuki
authors.forename: Hidetoshi
authors.initials: H
authors.lastname: Higuchi
authors.forename: Takeshi
authors.initials: T
authors.lastname: Okuhira
authors.forename: Akira
authors.initials: A
authors.lastname: Anri
mesh_terms: D000822:Animal Husbandry; D000818:Animals; D002417:Cattle; D002452:Cell Count / Q000662:veterinary; D003612:Dairying / Q000379:methods; D005260:Female; D008137:Longitudinal Studies; D008414:Mastitis, Bovine / Q000382:microbiology* / Q000517:prevention & control*; D008892:Milk / Q000382:microbiology*; D013203:Staphylococcal Infections / Q000382:microbiology / Q000517:prevention & control / Q000662:veterinary*; D013211:Staphylococcus aureus / Q000254:growth & development*