showed
mastitis signs of pronounced glandular hardening. The herd
characteristics included a semi-intensive dairy system and
the majority of the cows belonged to the Holstein breed. All
animals were vaccinated against foot-and-mouth disease
and brucellosis. Tuberculosis was routinely controlled, and
veterinarians and technical staff of a cooperative provided
assistance to the farmer. The cow underwent several
intramammary (aminoglycoside and b-lactam) and parenteral
(tetracyclines) antibiotic therapies with treatment
protocols for 2 weeks. Due to the lack of adequate response,
the owner requested milk bacteriological testing.