Análise do perfil de resistência a antimicrobianos de bactérias envolvidas em casos de mastite ovina.

Abstract

In sheep farming one of the main diseases in the productive activity is mastitis. The causal agents of the pathology include bacteria such as: Pseudomonas aeruginosa, Mannheimia haemolytica, corynebacteria, bacteria of the genus Staphylococcus spp., in addition to fungi. The main objective of this work was to evaluate the profile of bacteria in cases of ovine mastitis. Through in vitro isolation of collected samples, and antibiogram tests. It can be seen that in most studies the incidence of mastitis due to Staphylococcus ssp. involved in infectious mastitis. Cases of subclinical mastitis have also been identified with enterobacteria such as Salmonella sp. Characterized as environmental mastitis. The indiscriminate use of antimicrobials causes several problems in the production system, due to the resistance of bacteria, and the ineffectiveness of antimicrobials. The experimental design was carried out by selecting two producers with cases of mastitis in their herd, located in the cities of São Manoel and Botucatu-SP, both classified as humid sub-tropical. 10 animals were separated, which originated 20 samples (right and left ceiling), the samples were collected in sterile flasks, and refrigerated where they were taken to the microbiology laboratory of the UFSCar Lagoa do Sino campus for bacterial identification, and resistance tests to antimicrobials. Two bacteria of the Enterobacteriaceae family predominant in the study were identified, Salmonella ssp., and Escherichia coli. Soon after, the antibryogram tests were performed and the following antimicrobials were used for the study: Gentamicin 120μg, Amoxicillin + Clavulanic Acid 20/10μg, Sulfazotrim 25μg, Ciprofloxacin 5μg, Azithromycin 15μg and Tetracycline 30μg, which presented the following percentages of resistance to a certain bacterium, Salmonella sp.: Gentamicin (11.28%), Ciproflaxacin (22.22%), Tetracycline (77.77%), Azithromycin (88.88), Amoxicillin and Sulfazotrim (both 100%). And Escherichia Coli: Gentamicin (27.28%), Ciproflaxacin (54.54%), Tetracycline (45.45%), Azithromycin and Amoxicillin (both 81.81%), Sulfazotrim (90.90%). The cases of enterobacteria in mastitis indicate that the cause is of environmental origin. It can be said that the bacteria showed multiple resistance, there is more than one antimicrobial. Although they belong to the same family of bacteria, Salmonella sp., has a somewhat more aggressive profile than Escherichia coli, and the possibility that the study animals present salmonellosis, causing the antibiotics to have no effect, is not ruled out. Contrasting with the results obtained in the literature, it can be said that subclinical mastitis is prevalent in both cases, thus confirming the thesis that it is necessary to use methods of identifying it, and alternative therapies in the treatment.