title: Epidemiological typing of bovine streptococci by pulsed-field gel electrophoresis.
abstract: Pulsed-field gel electrophoresis (PFGE) was used to investigate the epidemiology of streptococcal mastitis in dairy cattle. The most prevalent streptococcal species, Streptococcus uberis (60-80% of streptococcal isolates), was highly heterogeneous, with different cows only rarely sharing the same pulsotype. S. agalactiae was rarely encountered, however all eight isolates from one farm generated identical PFGE profiles, which differed from those of all other isolates examined, confirming cow-to-cow transmission. Fifty-two isolates of S. dysgalactiae from 27 cows on 5 farms generated 6 different profiles. However, on individual farms, only one or two pulsotypes usually predominated. This species is generally regarded as an environmental pathogen but our data suggest that cow-to-cow transmission of S. dysgalactiae may occur. In spite of the variation in PFGE profiles of isolates from different cows, persistent infections in individual cows were usually caused by the same pulsotype of S. uberis or S. dysgalactiae.
authors.affiliation: Department of Applied Biology and Biotechnology, Royal Melbourne Institute of Technology, Australia.
authors.forename: S M
authors.initials: SM
authors.lastname: Wang
authors.forename: M A
authors.initials: MA
authors.lastname: Deighton
authors.forename: J A
authors.initials: JA
authors.lastname: Capstick
authors.forename: N
authors.initials: N
authors.lastname: Gerraty
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology* / Q000382:microbiology* / Q000635:transmission; D016521:Electrophoresis, Gel, Pulsed-Field; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000635:transmission / Q000662:veterinary*; D016985:Streptococcus bovis / Q000145:classification* / Q000302:isolation & purification