Identificação bacteriana e perfil de sensibilidade antimicrobiana de isolados uterinos de éguas virgens, resistentes e suscetíveis à endometrite

Abstract

Endometritis, characterized by inflammation of the endometrium, is an importante cause of infertility in mares and is associated with alterations in the uterine microbiota. This study aimed to identify and compare the uterine microbiota and the antimicrobial susceptibility profile of bacteria isolated from mares without endometritis (ES), mares with endometritis (EE) and virgin mares (EV). Seventeen mares were evaluated using low-volume uterine lavage, applying an adapted double-catheter technique to minimize contamination, followed by microbiological culture on blood agar, MacConkey agar, and MRS agar. A total of 92 microorganisms were isolated, of which 78 were identified by MALDI-TOF or Vitek, mainly belonging to the phyla Firmicutes and Proteobacteria. The genus Streptococcus was the most frequently isolated, followed by Escherichia and Staphylococcus, among other less prevalent genera. Blood agar showed the highest bacterial recovery rate. In antimicrobial susceptibility testing, 52.2% of the isolates exhibited multidrug resistance, with higher overall susceptibility to sulfamethoxazole-trimethoprim and ceftiofur, and high resistance to penicillin and erythromycin. These results highlight the complexity of the equine uterine microbiota, the concerning antimicrobial resistance scenario, and the need for complementary approaches in the management of endometritis.