First evidence of microplastics and their characterization in yellow-legged gull (Larus michahellis michahellis, Naumann, 1840) pellets collected from the Sfax salina, southeastern Tunisia.

The aim of this work was to provide evidence on the presence of microplastics (MPs) in regurgitated Yellow-legged Gull pellets (n = 18) from Sfax salina (south-eastern Tunisia). This artificial area is subject to high anthropogenic pressure and hosts Yellow-legged Gulls, which are at the top of the trophic chain and can be used as sentinel species to monitor litter in the environment, including plastic pollution. The total number of MPs found in the samples was 309, 63.8 % fibres (4.95 ± 3.51 MPs/g) and 36.2 % fragments (2.87 ± 1.74 MPs/g). Micro-FTIR analysis evidenced that a large proportion of the fibres was attributed to artificial cellulose (40.7 %). Ethylene vinyl acetate (EVA) and polyethylene (PE) were found in the fragments.

Microscopic and serological survey of Trypanosoma evansi infection in Tunisian dromedary camels (Camelus dromedarius).

Camels are the most adapted species to the harsh ecosystems of the African continent where they represent 80% of world's population. However, they can be susceptible to many pathogens such as Trypanosoma evansi. This parasite is widely distributed in Africa and represents a real threat to animal health and production. In Tunisia, despite its importance, this disease is underestimated and only a few data are available. The present study aims to investigate the prevalence of the disease by combining microscopic and serological tests. A cross-sectional study was conducted on 307 dromedary camels randomly selected from Southern Tunisia. Collected blood samples were microscopically examined and tested with Card Agglutination Trypanosomiasis Test to detect anti-T. evansi antibodies. The microscopic and serological prevalence were estimated at 2.93 and 62.54%, respectively. Microscopic examination showed morphological features of T. evansi. All positives samples were collected from aged males (>5 years old). Seroprevalence was similar for both sexes but it was higher in dry season and in the southwest of Tunisia. The present study revealed high prevalence of T. evansi infection among dromedary camels. This highlights the need for adequate control measures based on the detection and treatment of infected animals and vector control. We recommend investigating the prevalence of infection in other domestic animals living in the same environment.

First Report of KPC-2 and KPC-3-Producing Enterobacteriaceae in Wild Birds in Africa.

The increased incidence of antibiotic-resistant Enterobacteriaceae is a public health problem worldwide. The aim of this study was to analyze the potential role of wild birds, given their capacity of migrating over long distances, in the spreading of carbapenemase, extended-spectrum ß-lactamase (ESBL), and acquired-AmpC beta-lactamase-producing Enterobacteriaceae in the environment. Fecal and pellet samples were recovered from 150 wild birds in seven Tunisian regions and were inoculated in MacConkey-agar plates for Enterobacteriaceae recovery (one isolate/animal). Ninety-nine isolates were obtained and acquired resistance mechanisms were characterized in the five detected imipenem-resistant and/or cefotaxime-resistant isolates, by PCR and sequencing. The following ESBL, carbapenemase, and acquired-AmpC beta-lactamase genes were detected: blaCTX-M-15 (two Escherichia fergusonii and one Klebsiella oxytoca isolates), blaKPC-2 (one K. oxytoca), blaKPC-3 (one E. fergusonii), blaACT-36, and blaACC-2 (two K. oxytoca, four E. fergusonii, and two E. coli). The IncFIIs, IncF, IncFIB, IncK, IncP, and IncX replicons were detected among these beta-lactamase Enterobacteriaceae producers. The blaKPC-2, tetA, sul3, qnrB, and cmlA determinants were co-transferred by conjugation from K. oxytoca strain to E. coli J153, in association with IncK and IncF replicons. Our results support the implication of wild birds as a biological vector for carbapenemase, ESBL, and acquired-AmpC-producing Enterobacteriaceae.

Measure of environmental stress on Porcellio laevis Latreille, 1804 sampled near active Tunisian industrial areas.

This study aimed to observe the type of asymmetry exhibited by Porcellio laevis sampled from 15 sites belonging to Tunisian industrialized areas. Physicochemical parameters such as pH, organic matter and CaCO3 contents were measured in soils. Moreover, Cd, Pb, Zn, and Cu concentrations were determined in both soils and woodlice. Additionally, 10 metrical traits were measured to evaluate the type of asymmetry on individuals: the basis, the second and the third articles of the antenna, the first article of the flagellum of the antenna and the merus, the carpus, and the propodus of the sixth and the seventh pereopods. Among the 531 measured individuals, 432 exhibited fluctuating asymmetry (FA) while the remaining individuals exhibited antisymmetry or directional asymmetry. The data obtained were analyzed using a multivariate statistical analysis. Contrary to our hypothesis, the results showed that individuals from contaminated sites have a low FA level, whereas those from uncontaminated sites have a high FA level, particularly females but with some exceptions. Variations in FA level in the traits and populations studied and its usefulness as a stress indicator were discussed.

Antimicrobial resistance and genetic lineages of faecal enterococci of wild birds: Emergence of vanA and vanB2 harbouring Enterococcus faecalis.

Migrating birds have been implicated in pathogen dissemination over long distances. The lack of data on the intestinal microbiota of birds makes these animals a promising path in order to understand their potential role in the transmission of antibiotic-resistant bacteria. This study aimed to investigate the diversity of enterococcal species, and to analyse the antimicrobial-resistant phenotypes/genotypes, as well as the genetic lineages of isolates obtained from faecal and pellet samples of colonial wild birds in Tunisia. Seventy-nine enterococci were recovered from 150 wild birds, after inoculation of samples in Slanetz-Bartley agar, and were identified as E. faecalis (n = 53), E. faecium (n = 19) and E. casseliflavus (n = 7). Antimicrobial susceptibility was tested, and the following rates of resistance were found: tetracycline (46.8%); erythromycin (34.2%); chloramphenicol (8.8%); gentamicin and streptomycin (2.5-3.8%); ciprofloxacin, trimethoprim-sulfamethoxazole and kanamycin (12.7-21%); and ampicillin and linezolid (0%). The tet(M), tet(L), erm(B), erm(C), aac(6')-Ie-aph(2″)-Ia and cat genes were detected in most tetracycline-, erythromycin-, gentamicin- and chloramphenicol-resistant enterococci, respectively. Three vancomycin-resistant E. faecalis isolates were detected, two with the vanA gene (into Tn1546) and one with the vanB2 gene (into Tn5382); these isolates showed different sequence types determined by multi-locus sequence typing (ST9, ST16 and a new ST848). Seven E. casseliflavus isolates harbouring the intrinsic vancomycin resistance mechanism vanC2 were obtained. The gelE, ace, agg, esp and hyl virulence genes were detected among vanA/vanB2 enterococci. This study provides insight into the possible role of wild birds in the spread of certain antimicrobial resistance genes, particularly vanA/vanB2. To the authors' knowledge, this is the first report of vanB2-containing enterococci in Africa.