François S, Limansky A, Toresani I, Ebner G, Viale A, Sutich E

Language: English/Spanish
References: 13
Page: 305-310
PDF size: 108.99 Kb.

ABSTRACT

Streptococcus isolates present in milk of dairy cows presenting mastitis from the dairy areas of Santa Fe and Cordoba, Argentina, were characterized. From 169 milk samples, 30 isolates were recovered, and identified by both biochemical and serological studies as S. agalactiae (22 isolates), S. dysgalactiae (6 isolates) and S. uberis (2 isolates). RAPD genotypic analysis showed that 4 distinct clones were present in the S. agalactiae population, 6 in that of S. dysgalactiae, and 2 in S. uberis. Interestingly, each of the 4 different herds analyzed was colonized by a single and distinct clone of S. agalactiae, whilst different clones of S. dysgalactiae were found to coexist in a herd. A DNA fragment common to all assayed isolates of S. agalactiae was identified; it was absent in the other species. Results above indicate that the employed methodologies constitute a powerful tool for diagnostic- and epidemiological surveillance of Streptococci in dairy cows.

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