Background: Increasing consumer demand for healthier food products has led to the development of governmental policies regarding health claims in many developed countries. In this context, contamination of poultry by food-borne pathogens is considered one of the major problems facing the progress of the poultry industry in Tunisia. Result: Zeolite (Clinoptilolites) was added to chicken feed at concentrations 0,5% or 1% and was evaluated for its effectiveness to reduce total flora in chickens and its effects on performance of the production. The broilers were given free and continuous access to a nutritionally non-limiting diet (in meal form)that was either a basal diet or a' zeolite diet' (the basal diet supplemented with clinoptilolite at a level of 0,5% or 1%). It was found that adding zeolite in the broiler diet significantly (p < 0,05) reduced total flora levels, as compared to the control, on the chicken body. In addition, it was found that zeolite treatment had a positive effect on performance production and organoleptic parameters that were measured and mainly on the increase level of Omega 3 fatty acid. Conclusion: This study showed the significance of using zeolite, as a feed additive for broilers, as part of a comprehensive program to control total flora at the broiler farm and to increase level of Omega 3 fatty acid on the chicken body.

This study investigated the biological activities of a hydroxytyrosol‐rich extract from Olea europaea leaves, particularly its ability to eradicate severe pathogenic bacteria producing Extended‐Spectrum Beta‐Lactamases (ESBLs). The latter bacteria are emerging microorganisms that pose significant challenges due to their resistance to a broad range of potent therapeutic drugs.The extract was prepared through an accessible acid hydrolysis method. In vitro and In silico analyses through MIC, MBC analysis and molecular docking were conducted to evaluate the antibacterial properties.The extract showed remarkable antioxidant activity and significant antibacterial potential against reference species and ESBL bacteria. MIC and MBC calculations confirmed the extract's capacity to kill bacteria rather than just inhibit their growth. Further in silico analyzes demonstrated the high binding affinity of HT to the active sites of the gyrase B subunit and the peptidoglycan DD‐transpeptidase domain from proteins located in the cytoplasm and the cell wall of the bacteria, respectively. Results confirmed the structure‐activity relationship and the ability of HT to disrupt essential bacterial functions.This study validates the debated antimicrobial potential of HT and highlights its importance as a potential therapeutic agent against resistant bacteria, which is a critical area of research given the global challenge of antibiotic resistance.

Salmonella is a leading cause of foodborne diseases worldwide. The use of antibiotics in food-producing animals may contribute to the development of antimicrobial resistance in nontyphoida...

Non-typhoidal Salmonella (NTS) strains are among the major foodborne pathogens with emerging multidrug-resistant phenotypes. In this study, antimicrobial susceptibilities of a collection of Salmonella isolates (n=54) recovered from poultry and bivalve molluscs were performed. The study also investigated the virulence and resistance genes profiling as well as the phylogenetic relationships through PFGE and ERIC/PCR fingerprinting. Results revealed the presence of multiple virulence genes among Salmonella isolates. siiA , sopB , cat2 , safC , sefB and sopE2 genes were present in most (83.32%-100%) of the isolates, while the remaining tested genes ( spvC , spvB, and sopE ) were exclusively detected within the serotype Enteritidis. The highest resistance rates were observed for oxacillin (94.4%), ampicillin (37%) and nalidixic acid (27.7%), followed by cefotaxime and amoxicillin/clavulanic acid (14.8%), trimethoprim/sulfamethoxazole (9.3%) and ciprofloxacin (5.5%). The results of the present study indicate that S. Enteritidis serotype possessed the widest range of virulence determinants and increasing levels of resistance. Such high-risk clones should be particularly controlled in Tunisia. Overall, increased resistance and virulence confers a selective advantage for the evolution of the bacteria which represents an alarming problem for global public health. The genetic study via Pulsed-field gel electrophoresis (PFGE) and enterobacterial repetitive intergenic consensus PCR (ERIC/PCR) showed the high diversity of the clonal origins of the bacteria and the sources of contamination,and revealed the great capacity of the pathogen to diversify within food-producing animals.

Urinary tract infections (UTIs) are the most frequent human infections in community and hospitals. This study aimed to determine the distribution of bacterial uropathogens among urinary tract infections diagnosed within the regional hospital Houcine Bouzaiene (Gafsa, South West Tunisia) during a survey of 54 days from the 8th of November to the 31st of December 2017.Enterobacteralesstrains were tested for antimicrobial resistance by disk diffusion method and extended-spectrum β-lactamase (ESBL) production was tested by double-disc synergy test. Strains were further subjected to a molecular assessment of ESBL and AmpC β-lactamase production by PCR.Overall, 173 bacterial isolates were studied, out of which 91.3% wereEnterobacterales.Escherichia coliwas the dominant pathogen, followed byKlebsiella pneumoniae. High to moderate resistance rates were observed, ranging from 66% to 90.7% for penicillins, from 6.7% to 18.6% for cephalosporins and from 16.2% to 25.4% for fluoroquinolones.Enterobacteraleswith decreased susceptibility to third-generation cephalosporins (3rd GC) carried several resistance genes:blaCTX-M group 1 and group 9, and ACC and FOX AmpC β-lactamase genes. Overall, ESBLs and AmpC β-lactamases were detected in 57% and 14% of the 3rd GC-resistant isolates, respectively.This study proved the high potential ofK. pneumaniaespecies to develop resistance against commonly used antibiotics. Thus, rigorous monitoring of the antibiotic resistance of clinical pathogens have to be implemented in Tunisia. Our results are very relevant to evaluate efficiency of the Tunisian therapeutic strategies against UTIs and adapt them to the emerging problem of antimicrobial resistance.