[Acute severe mastitis in cows of the Dutch-Friesian Breed (author's transl)].

One hundred cases of severe acute mastitis are reported. Bacteriological examination of the milk was negative in 23% of the cases. E. coli was most frequently found to be the causative organism (23%), followed by St. aureus (19%), C. pyogenes (10%), Str. dysgalactiae (9%), Str. agalactiae (5%) and a number of other pathogenic agents such as atypical streptococci, Str. uberis, haemolytic streptococci, Aerobacter aerogenes, Kl. pneumoniae, a clostridium and P. multocida. In several cases, a tentative diagnosis may be based on the clinical symptoms, which is then found to be correct on bacteriological examination of the milk. The prognosis will vary with the causative organism. Treatment was life-saving in more than 90% of the cases, the milk-producing capacity of the affected quarter being completely preserved in 36% and partly preserved in 27% of the cases.