Ribotyping of Streptococcus uberis from a dairy's environment, bovine feces and milk

• Published in: Veterinary microbiology 2005-08, Vol.109 (3), p.257-265
• Main Authors: Zadoks, Ruth N., Tikofsky, Linda L., Boor, Kathryn J.
• Format: Article
• Language: English
• Subjects: animal pathogenic bacteria; Animals; bacterial infections; Bacteriology; Biological and medical sciences; bovine mastitis; Cattle; dairy cows; Dairying; disease transmission; DNA fingerprinting; DNA, Bacterial - chemistry; DNA, Bacterial - genetics; Environment; Environmental Microbiology; environmental samples; Fecal; feces; Feces - microbiology; Female; Fundamental and applied biological sciences. Psychology; mammary involution; Mastitis; Mastitis, Bovine - microbiology; Mastitis, Bovine - transmission; Microbiology; milk; Milk - microbiology; Miscellaneous; Polymerase Chain Reaction - veterinary; Ribotyping - veterinary; Seasons; Soil; strain differences; strains; Streptococcus - classification; Streptococcus - genetics; Streptococcus uberis
• ISSN: 0378-1135; 1873-2542
• DOI: 10.1016/j.vetmic.2005.05.008

Streptococcus uberis is a major cause of bovine mastitis and infections commonly result from environmental exposure to the pathogen. To identify specific sources of mastitis-causing S. uberis strains, samples were collected monthly from the environment and feces of dry cows in a grazing herd. Environmental and fecal strains of S. uberis were compared to those found in milk. S. uberis was detected in 63% of 94 environmental samples, including water, soil, plant matter, bedding material, flies, and hay, in 23% of 107 fecal samples, and in 4% of 787 milk samples. Automated PvuII ribotyping revealed 48 ribotypes among 266 isolates. Per sample, up to five ribotypes were detected. The distribution of ribotypes did not differ significantly among environmental, fecal and milk samples. Specific environmental sources or strains of udder-pathogenic S. uberis were not identified. Fecal shedding was not persistent and did not differ between dry-off and calving. The proportion of fecal samples containing S. uberis was highest during the summer grazing season. S. uberis was common in farm soil (31 of 35 samples) but not in non-farm soil (0 of 11 samples). We hypothesize that fecal shedding of S. uberis may play a role in maintenance of S. uberis populations in the dairy ecosystem.