The study aimed to verify the occurrence of aerobic bacteria causing liver macroscopic lesions in sheep and goats, besides describing the susceptibility profile to antimicrobials and the pathogenic potential of the isolated bacterial species. The samples were collected during the slaughter of 1,270 animals in slaughterhouse under Federal Inspection Service (SIF) in the municipality of Feira de Santana, Bahia, Brazil. Fragments were placed in sterile containers and sent to the Laboratory of Inspection and Technology of Meat and Derivatives (LABCARNE). Escherichia coli was the most frequently isolated microorganism, present in the liver of 35 animals, followed by Streptococcus spp. (8 animals), Staphylococcus spp. (6 animals) and Bacillus spp. (5 animals). In the profile analysis of antimicrobial susceptibility, strains of E. coli, Streptococcus spp. and Staphylococcus spp. tested showed at least 50% resistance to ampicillin, penicillin, ceftazidime, erythromycin and rifampicin. From these strains, 27%, 67% and 60%, respectively, submitted a multidrug resistance profile. In this study, abscesses were the main cause of goat and sheep livers condemnation, E. coli was the most isolated microorganism in livers with and without macroscopic lesions. The antimicrobials with the highest frequency of resistance in tested strains were ampicillin, penicillin and erythromycin.

Keywords: sheep, goat, microbiology, condemnation, liver.