Mamite no rebanho bovino da Escola Média de Agricultura de Florestal - UFV-MG;: I - Contole através da desinfecção pós-ordenha e do uso do Trimethoprim-Sulfametoxazole. II - Freqüência e etiologia

The efficiency of glycerine iodine teat dip under normal and abnormal milking machine operation was observed in the EMAF-UFV-MINAS GERAIS-BRAZIL dairy herd during an 8 month period. California Mastitis Test (C.M.T), Direct Microscopic Count (DMC), Bacterioscopic and Bacteriology were used for evaluation purposes. The results: PHASE I In the period from january-april/76, 82 animals were observed. When C.M.T., DMC, and Bacterioscopic results were analyzed by Chi-square, teat dip vs not teat dip were not significantly difference. Post milking teat dip did not avoid the new intrammamary infections (x² = 3,12). The reduction os Staphylococcus aureus infections was 23,60% and Streptococcus uberis infections was 3,03% when there was evidence of milking machine vacuum fluctuation and overmilking. These conditions are considered abnormal. PHASE II In the period may to August/76, 61 animals were observed under normal Milk procedures (no overmilking or vacuum fluctuatuions). The post-milking teat dip results under the above condition did prevent new mastitis cases (x² = 12,45). The reduction of Staphylococcus aureus and Streptococcus uberis was 67,60% and 44,44%%. The frequence of microorganism isolated in mastitis cases was dtermined. Staphylococcus aureus incidence was 83,54% and Streptococcus uberis was 13,98%. They were the most common bactéria in the herd. The treatment of mastitis was made by Trimethoprim-Sulphametoxazole (TMP-SMZ), into teat canal, with one, two or three doses at 24 hours intervals. No significance difference (x² = 0,77) was found among number of doses. TMP-SMZ showed low efficiency for staphylococcal mastitis (34,28%). Streptococcus uberis (76,00%) was more sensitive to treatment. The increase number of cells indicated irritation, induced by vehicle water/oil, was more evident between 48-72 hours. After seven days DMC indicated cell counts had returned to initial levels.