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In this study, a culture-independent approach was applied to compare the microbiome composition and the abundance of the antimicrobial resistance genes (ARGs) aadA2 for aminoglycosides, tet(A), tet(B), tet(K), and tet(M) for tetracyclines, and mcr-1 for colistin in broiler litter samples collected from conventional and antibiotic-free flocks located in Central Italy. A total of 13 flocks and 26 litter samples, collected at the beginning and at the end of each rearing cycle, were submitted to 16s rRNA sequence analysis and quantitative PCR for targeted ARGs. Firmicutes resulted in the dominant phylum in both groups of flocks, and within it, the Clostridia and Bacilli classes showed a similar distribution. Conversely, in antibiotic-free flocks, a higher frequency of Actinobacteria class and Clostridiaceae, Lactobacillaceae, Corynebacteriaceae families were reported, while in the conventional group, routinely treated with antibiotics for therapeutic purposes, the Bacteroidia class and the Enterobacteriaceae and Bacillaceae families were predominant. All investigated samples were found to be positive for at least one ARG, with the mean values of aadA2 and tet(A) the highest in conventional flocks by a significant margin. The results suggest that antibiotic use can influence the frequency of resistance determinants and the microbial community in poultry flocks, even though other environmental factors should also be investigated more deeply in order to identify additional drivers of antimicrobial resistance. [ABSTRACT FROM AUTHOR]

The Apennine wolf (Canis lupus italicus) is a subspecies of gray wolf that is widespread throughout Italy. Due to hunting and habitat loss, their population declined dramatically in the late 19th and early 20th centuries, but conservation efforts improved to restore the species to an estimated population of 3300 individuals. The presence of antibiotic-resistant bacteria in Apennine Wolf may pose a risk to its health and survival, as well as the health of other animals in its environment. In this study, we investigated the antibiotic resistance profiles of bacteria collected from Apennine wolves admitted to the Wildlife Research Center of Maiella National Park (Italy) in 2022. A total of 12 bacteria collected from four wolves were isolated and tested for susceptibility to antibiotics used in veterinary medicine and to critically important antibiotics for human health by means of the Vitek 2 system. All isolates were resistant to at least one antibiotic, and six bacteria were multidrug resistant to critically important antibiotics (third-generation cephalosporins, carbapenems and fluoroquinolones). The results of this pilot study have allowed for the characterization of resistant profiles in Escherichia coli, Enterococcus faecalis and other bacterial species not previously reported in Apennine wolves. Our findings provide important insights into antibiotic resistance in wildlife and its potential implications for the conservation of biodiversity and public health. [ABSTRACT FROM AUTHOR]

The available data on antimicrobial resistance in pets are limited compared to those collected for food-producing animals. Bacterial urinary tract infections are some of the most important indications for antimicrobial use in pets, and empiric antimicrobial treatments are often administered in the presence of clinical signs. In this study, the results obtained from the laboratory investigations carried out on dogs and cats with urinary tract infections coming from veterinary clinics and practices in Central Italy were evaluated to provide additional data concerning the bacterial urinary pathogens and their antimicrobial resistance patterns in pets. A total of 635 isolates were collected from urine samples. Escherichia coli was the most common species recovered in dogs and cats, followed by Proteus mirabilis and Enterococcus spp. Furthermore, it was possible to isolate bacteria not usually described in other studies concerning pets such as Pantoea dispersa, Raoultella ornithinolytica, and Pasteurella pneumotropica (also known as Rodentibacter pneumotropicus). Based on the antimicrobial susceptibility results, 472/635 (74.3%) isolates were resistant to at least one antibiotic and 285/635 (44.8%) isolates were classified as multidrug-resistant. Monitoring the antibiotic resistance profiles in pet infections is important not only for the public health implications, but also to collect data useful for the treatment of diseases in pets. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the resistance patterns against selected critically and highly important antibiotics (quinupristin/dalfopristin, vancomycin, and linezolid) in 48 Enterococcus isolates obtained from wild (red deer and Apennine chamois) and domestic (cattle, sheep, and goats) ruminants living with varying degrees of sympatry in the protected area of Maiella National Park (central Italy). According to CLSI breakpoints, 9 out of 48 isolates (18.8%) showed resistance to at least one antibiotic. One Apennine chamois isolate was resistant to all tested antibiotics. The PCR screening of related resistance genes highlighted the occurrence of msrC or cfrD in seven Enterococcus resistant isolates. In addition, msrC and vanC genes were amplified in susceptible isolates. Specific sequences of virulence genes (gelE, ace, efa, asa1, and esp) related to pathogenic enterococci in humans were amplified in 21/48 isolates (43.75%), belonging mostly to wild animals (15/21; 71.42%). This is the first report of linezolid-resistant enterococci harboring virulence genes in Italian wildlife with special regard to the red deer and Apennine chamois species. The results allow us to evaluate the potential role of wild animals as indicators of antibiotic resistance in environments with different levels of anthropic pressure. [ABSTRACT FROM AUTHOR]