Lucas Possa Oliveira

Foods can be contaminated by a wide range of microorganisms, originating from multiple sources within domestic kitchens. However, the role of flies and ants as carriers of bacteria in these environments remains poorly understood, and data on the antimicrobial susceptibility profiles of insect-associated bacteria remain scarce. Therefore, this study aimed to identify Enterobacterales and Staphylococcus spp. recovered from flies and ants collected in domestic kitchens and to characterize the antimicrobial susceptibility profiles of the isolates. Additionally, selected virulence genes were investigated in Staphylococcus aureus and Escherichia coli, two recognized foodborne pathogens. A total of 240 insects (113 flies and 127 ants) were collected from 58 domestic kitchens. Twenty-six Enterobacterales isolates belonging to nine species were recovered from 17 kitchens, including a single multidrug-resistant (MDR) isolate identified as Enterobacter hormaechei. In addition, 45 staphylococcal isolates representing nine species were recovered from 25 kitchens, originating from 36 flies and 9 ants. Among these, 13 isolates exhibited an MDR phenotype, including S. aureus and several non-aureus Staphylococcus species. None of the E. coli isolates carried the eae or stx1/stx2 genes, whereas none of the S. aureus isolates harbored the sea, seb, sec, see, or mecA genes. To the best of our knowledge, this is the first study to report the simultaneous recovery of MDR bacteria from flies and ants collected in domestic kitchens. These findings provide new evidence that household insects may act as carriers of antimicrobial-resistant bacteria, highlighting their potential role in the dissemination of clinically relevant bacterial species, including MDR strains, within domestic environments. Effective insect control and good household food hygiene practices may help reduce the spread of antimicrobial-resistant bacteria and mitigate the risk of difficult-to-treat foodborne infections.

The emergence of antimicrobial resistance (AMR) is a critical One Health problem, with wildlife increasingly threatened. While captive giant anteaters (Myrmecophaga tridactyla) have been studied for microbiota composition and AMR, wild-living individuals have not yet been investigated. Therefore, this study investigated the Gram-negative aerobic microbiota colonizing 21 wild M. tridactyla individuals and evaluated the phenotypic and genotypic AMR profiles of enterobacteria. Accordingly, 67 enterobacteria and non-fermenting Gram-negative bacilli were identified, with Escherichia coli, Pseudomonas sp., and Achromobacter sp. being observed in all swab types (oral, ocular, and rectal). Among 12 enterobacteria, three E. coli strains were identified as resistant to antimicrobials, with the TMND-VV-15 strain, isolated from a peri-urban specimen, exhibiting multidrug resistance and producing an extended-spectrum β-lactamase (ESBL). Genome sequencing of the TMND-VV-15 strain revealed AMR determinants, including horizontally acquired genes and chromosomal point mutations associated with resistance. The bla_CTX-M-2 gene was harbored in a complex class 1 integron located on its chromosome. Potential virulence genes mainly related to adhesion, invasion, immune evasion, and host cell damage were found. Strain TMND-VV-15 belonged to the sequence type (ST) 1266 and sublineage E-ST1266-H108. Comparative genomic analysis revealed that E-ST1266-H108 strains, including those harboring ESBL genes and classified as putative enteropathogenic E. coli, have been circulating in many countries, but not in Brazil. These findings suggest that the CTX-M-2-producing E. coli strain may be driven by anthropogenic pressures in the area studied. Therefore, continuous microbiological monitoring in free-ranging populations remains necessary to better understand the dynamics of AMR dissemination to the wildlife health framework.

Vitamin D and its prohormones have become the focus of increasing research in recent years, revealing functions beyond calcium metabolism and bone formation. This includes interactions with the immune system, given the widespread expression of the vitamin D receptor in various body tissues such as the brain, heart, skin, intestine, gonads, prostate, breasts, and immune cells, in addition to bones, kidneys, and parathyroids. Recommended values vary across different information sources, largely dependent on the conditions under which they were established (experimental, commercial, or field-based). However, it is the nutritionist's role to adapt these values to specific production conditions and goals. Thus, this literature review aims to clarify the mechanism of metabolism, acquisition, and contribute to the controversy surrounding Vitamin D deficiency and Hypervitaminosis in pigs from the weaning of piglets to the finishing phase.