Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): antimicrobial-resistant Enterococcus faecalis in poultry

Caffeic acid phenethyl ester attenuates Enterococcus faecalis infection in vivo: antioxidants and NF-κB have a protective role against stomach damage

The mammalian gastrointestinal tract hosts a significant microbial symbiont community, an intriguing feature of this complex organ system. This study aimed to investigate the anti-inflammatory, antioxidant, and protective effects of caffeic acid phenethyl ester (CAPE) against Enterococcus faecalis infection in the stomach at a dose of 106 CFU in Swiss mice. A total of 30 mice were randomly assigned to three groups of ten mice each. Group I was the negative control, Group II was infected orally with E. faecalis for 18 days, and Group III was infected with E. faecalis and treated with CAPE orally at a daily dose of 4 mg/kg for 18 days. We assessed the antioxidant activities of stomach homogenate and the immunohistochemical expressions of the transcription factor nuclear factor kappa B (NF-κB) and proliferating cell nuclear antigen (PCNA). Histopathological examination was performed on the stomachs of all mice. Group II had decreased levels of antioxidant activity and positive expressions of NF-κB and PCNA. Histological observations revealed an increase in mucosal and glandular thickness compared with Group I. Group III, treated with CAPE, showed a significant increase in antioxidant activities and a significant decrease in NF-κB and PCNA immunoreactivities compared with Group II. In addition, Group III showed restoration of the normal thickness of the non-glandular and glandular parts of the stomach. Our results revealed that E. faecalis infection has damaging effects on the stomach and proved that CAPE has promising protective, anti-inflammatory, and antioxidant effects against E. faecalis. Further studies may investigate the potential therapeutic effects of CAPE against E. faecalis infection.

Nasotracheal Microbiota of Nestlings of Parent White storks with Different Foraging Habits in Spain

Migratory storks could be vectors of transmission of bacteria of public health concern mediated by the colonization, persistence and excretion of such bacteria. This study aims to determine genera/species diversity, prevalence, and co-colonization indices of bacteria obtained from tracheal (T) and nasal (N) samples from storks in relation to exposure to point sources through foraging. One-hundred and thirty-six samples from 87 nestlings of colonies of parent white storks with different foraging habits (natural habitat and landfills) were obtained (84 T-samples and 52 N-samples) and processed. Morphologically distinct colonies (up to 12/sample) were randomly selected and identified by MALDI-TOF-MS. About 87.2% of the total 806 isolates recovered were identified: 398 from T-samples (56.6%) and 305 from N-samples (43.4%). Among identified isolates, 17 genera and 46 species of Gram-positive and Gram-negative bacteria were detected, Staphylococcus (58.0%) and Enterococcus (20.5%) being the most prevalent genera. S. sciuri was the most prevalent species from T (36.7%) and N (34.4%) cavities of total isolates, followed by E. faecalis (11.1% each from T and N), and S. aureus [T (6.5%), N (13.4%)]. Of N-samples, E. faecium was significantly associated with nestlings of parent storks foraging in landfills (p = 0.018). S. sciuri (p = 0.0034) and M. caseolyticus (p = 0.032) from T-samples were significantly higher among nestlings of parent storks foraging in natural habitats. More than 80% of bacterial species in the T and N cavities showed 1-10% co-colonization indices with one another, but few had ≥ 40% indices. S. sciuri and E. faecalis were the most frequent species identified in the stork nestlings. Moreover, they were highly colonized by other diverse and potentially pathogenic bacteria. Thus, storks could be sentinels of point sources and vehicles of bacterial transmission across the "One Health" ecosystems.

Antimicrobial-Resistant Enterococcus spp. in Wild Avifauna from Central Italy

Bacteria of the genus Enterococcus are opportunistic pathogens, part of the normal intestinal microflora of animals, able to acquire and transfer antimicrobial resistance genes. The aim of this study was to evaluate the possible role of wild avifauna as a source of antimicrobial-resistant enterococci. To assess this purpose, 103 Enterococcus spp. strains were isolated from the feces of wild birds of different species; they were tested for antimicrobial resistance against 21 molecules, vancomycin resistance, and high-level aminoglycosides resistance (HLAR). Furthermore, genes responsible for vancomycin, tetracycline, and HLAR were searched. E. faecium was the most frequently detected species (60.20% of isolates), followed by E. faecalis (34.95% of isolates). Overall, 99.02% of the isolated enterococci were classified as multidrug-resistant, with 19.41% extensively drug-resistant, and 2.91% possible pan drug-resistant strains. Most of the isolates were susceptible to amoxicillin/clavulanic acid (77.67%) and ampicillin (75.73%), with only 5.83% of isolates showing an ampicillin MIC ≥ 64 mg/L. HLAR was detected in 35.92% of isolates, mainly associated with the genes ant(6)-Ia and aac(6′)-Ie-aph(2″)-Ia. Few strains (4.85%) were resistant to vancomycin, and the genes vanA and vanB were not detected. A percentage of 54.37% of isolates showed resistance to tetracycline; tet(M) was the most frequently detected gene in these strains. Wild birds may contribute to the spreading of antimicrobial-resistant enterococci, which can affect other animals and humans. Constant monitoring is essential to face up to the evolving antimicrobial resistance issue, and monitoring programs should include wild avifauna, too.