Main agents that cause mastitis in dairy cattle in the western region of Santa Catarina

Abstract

The objective of the study was to isolate and identify the main microorganisms that cause clinical and subclinical mastitis in dairy cattle in the West region of Santa Catarina and the sensitivity and resistance relationship of pathogens found by the antibiogram method, against the frequently used antimicrobials in treatments. Twenty-six samples of milk from bovines with mastitis disease were used, with distinction of race, age and weight, from small, medium and large farms. Clinical mastitis was identified by the clinical signs of edema, redness, increased temperature, hardening and pain in the mammary gland and subclinical mastitis was evidenced by the California Mastitis Test (CMT) and increased Somatic Cell Count (CCS). Thirteen microorganisms were identified, of which 12 (92%) were bacteria, the highest number of isolates belonging to the group of Staphylococcus ssp, Streptococcus ssp and Escherichia coli and one (8%) sample of yeast. The antibiogram identified the drugs with the most satisfactory sensitivity profile, being Amoxicillin, Ampicillin and Gentamicin with 83% of the samples showing sensitivity and the resistance of 58% of the samples facing the drug Oxacillin. The present study made possible the epidemiological survey and contribution to select the effective treatment, with reduced resistance to antibiotics.