First report of Acinetobacter spp. and Proteus mirabilis isolated from aborted ovine fetuses.

This report describes two cases involving the isolation of Acinetobacter spp. and Proteus mirabilis from aborted ovine fetuses in Northeastern Brazil, representing the first documented occurrence of this association worldwide. In case 1, Acinetobacter spp. was isolated from a hepatic abscess in a White Dorper fetus, accompanied by placental lesions. In case 2, A. baumannii and P. mirabilis were isolated from the brain and lungs of three Santa Inês fetuses, with pathological findings consistent with acute septicemia. In both cases, bacteria were identified through culture and biochemical testing, without molecular confirmation, and no laboratory testing was conducted to exclude classical abortifacients (Brucella spp., Campylobacter spp., Coxiella burnetii, Chlamydia abortus, Listeria spp., Salmonella spp., Toxoplasma gondii, and Neospora caninum), representing a study limitation. Nevertheless, the results highlight the potential opportunistic role of these microorganisms, the detection of antimicrobial resistance profiles, and the importance of including them in the investigation of reproductive losses, particularly in settings with limited diagnostic resources. These findings reinforce the need for integrated surveillance in animal and public health under the "One Health" approach.