RESUMO
A total of 183 coagulase negative Staphylococcal infected quarters and 64 uninfected quarters were randomly allotted to 4 experimental groups: infected quarters that did not receive any treatment [positive control group; n = 60]; infected quarters that received Tylosin [n = 61] or Cefquinome [n = 62] and also uninfected quarters that did not receive any treatment were considered as negative control group [n = 64]. Treated heifers received Tylosin or Cefquinome 10 to 14 days before the expected calving date. The bacteriological cure rate based on sampling obtained 3 days after calving was significantly higher [P<0.01] in mammary glands treated with systemic Tylosin [85.3%] than in the positive control group and mammary glands treated with systemic Cefquinome [69.4%]. At the same time Tylosin treated heifers had significantly lower [P<0.01] somatic cell count scores compared to the positive control and Cefquinome groups. With the exception of one heifer that calved 8 days earlier than the expected calving date, there was no detectable antibiotic residues in the milk of the treated heifers on the 3rd day of lactation