Prevalence of clinical mastitis in 38 Waikato dairy
herds
S. McDougall
Animal Health Centre, PO Box 21, Morrinsville
Proceedings of the New Zealand Society of Animal Production. 1998,
58: 76-78
The apparent prevalence of clinical mastitis was determined in
38 spring calving dairy herds as part of a larger field trial conducted
on behalf of Boehringer Ingelheim NZ Ltd between the 8th of July and the
21st of August, 1997. A total of 798 quarters from 595 cows were
diagnosed by herdowners as having clinical mastitis. Bacterial culture
was performed on all clinical quarters and antibiotic sensitivity
testing was performed on selected bacterial isolates. Clinical mastitis
was diagnosed in an average of 10.0% (± 0.8%, range 0.9% to 21.4%) of
calved cows within the herds. No bacteria were cultured from 28.2% of
clinical quarters. Of the quarters from which bacteria were cultured,
74.7% were Streptococcus uberis, 10.2% were coagulase negative
staphylococci, 4.7% were Coliforms, 4.1% were Streptococcus
dysgalactiae, 2.9% were Staphylococcus aureus and 3.3% were other
species of bacteria. Penicillin resistance was detected in 25% of 44
Staphylococcus aureus isolates, 0% of 10 Streptococcus uberis isolates
and 100% of 12 E. coli isolates.
Keywords: NZSAPAB;
Dairy Cattle; Mastitis; Early lactation; Prevalence.
Last Updated 12-09-1998
