Streptococci and enterococci associated with tonsils of cattle.

Streptococcus suis, Streptococcus bovis and the mastitis pathogens Streptococcus dysgalactiae and Streptococcus uberis were the most frequently occurring streptococci in tonsils of cattle. Streptococcus suis dominated in samples from calves between 1 month and 1 year of age, but was much less frequent in calves less than 1 month old. The mastitis pathogen Strep. dysgalactiae was found more often in calves than in older animals. Enterococci were relatively rare, except in the youngest age group. Nearly one third of the strains examined could not be identified to known species.