Antimicrobial Resistance and Biofilm in Bacteria from Rehabilitated Sapajus libidinosus.

Antimicrobial resistance (AMR) in natural environments and wildlife is an escalating threat to global health and biodiversity conservation. Neotropical primates of the genus Sapajus may act as reservoirs and ecological sentinels of resistant bacteria. The absence of systematic microbiological screening in wildlife rehabilitation centers, coupled with empirical antimicrobial use, can facilitate resistance spread in vulnerable ecosystems. This study characterized phenotypic and genotypic resistance profiles and biofilm-forming ability of Staphylococcus spp. and Mammaliicoccus sciuri isolated from Sapajus libidinosus undergoing rehabilitation in Northeastern Brazil. Rectal swabs were collected, and bacterial isolates identified by MALDI-TOF MS, followed by antimicrobial susceptibility testing, molecular detection of resistance genes, and biofilm assays. Nineteen isolates were recovered: 63.2% Staphylococcus spp. and 36.8% Mammaliicoccus spp. The predominant species were M. sciuri (36.8%) and S. simiae (31.6%). Rates of resistance to penicillin (63.2%) and tetracycline (57.9%) were the most frequent. The main resistance genes detected included tetM (36.8%), tet(38) (31.6%), blaZ (26.3%), msrA (26.3%), and mecA (5.3%). Perfect agreement existed between mecA presence and cefoxitin resistance (κ = 1.00; p < 0.01), with moderate agreement between msrA and non-susceptibility to erythromycin and clindamycin (j= 0.56; p = 0.0265). Biofilm production was mostly weak (94.7%), with moderate production in one isolate. Multidrug resistance occurred in 21.1% of isolates. This pioneering Brazilian study highlights wildlife rehabilitation centers as critical hotspots for AMR surveillance and contributes to understanding the ecological health and conservation of Neotropical primates.