First report of Corynebacterium pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig (Sus scrofa domesticus).

BACKGROUND: Corynebacterium pseudotuberculosis is the etiologic agent of caseous lymphadenitis, a common disease in small ruminant populations throughout the world and responsible for a significant economic impact for producers. CASE PRESENTATION: To our knowledge, this is the first characterization of C. pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig (Sus scrofa domesticus). In this study, phenotypic and genotypic identification methods allocated the swine isolates in C. pseudotuberculosis biovar ovis. The vast majority of the isolates were able to produce phospholipase D and were susceptible to most of the antimicrobial compounds tested. Macrorestriction patterns obtained by Pulsed Field Gel Electrophoresis (PFGE) grouped the C. pseudotuberculosis in two clusters with a high similarity index, which reveals their clonal relatedness. Furthermore, swine isolates were compared with C. pseudotuberculosis from caprines and PFGE patterns also showed high similarity, suggesting the prevalence of dominant clones and a potential cross-dissemination between these two animal hosts. CONCLUSIONS: This work represents the first report of Corynebacterium pseudotuberculosis from caseous lymphadenitis lesions in Black Alentejano pig and alerts for the importance of the establishment of suitable control and sanitary management practices to control the infection and avoid further dissemination of this important pathogen to other animal hosts.

Genotypic and phenotypic comparison of Escherichia coli from uterine infections with different outcomes: clinical metritis in the cow and pyometra in the bitch.

Escherichia coli uterine infection originates different clinical outcomes in the canine and bovine species. Here, E. coli strains isolated from bovine clinical metritis and canine pyometra cases were analyzed by PFGE, screened for 33 virulence factor (VF) genes and for phylogenetic grouping. Bovine and canine E. coli isolates presented a low degree of genetic similarity. Canine E. coli strains belonged to phylogenetic group B2 and presented a high number of VF genes, whereas bovine E. coli strains belonged to phylogenetic groups B1 and A and had a low number of VF genes. In conclusion, E. coli strains isolated from cow clinical metritis had a low potential of virulence. In contrast, bitch pyometra E. coli isolates had a high virulence potential, which might be relevant in the pathogenesis of pyometra. These differences between canine and bovine E. coli isolates may partially explain the different outcomes of the uterine infection in the two species.

Dynamics of bovine intramammary infections due to coagulase-negative staphylococci on four farms.

The objectives of this study were to compare the impact of different coagulase-negative species (CNS) on udder health measured in terms of individual quarter milk somatic cell count (SCC) and duration of intramammary infection, and to get some insight into most likely routes of infection for different CNS species. This longitudinal observational study was performed on four farms that were sampled at 4-week intervals for a total of 12 visits each. Quarters infected with CNS were followed through time with milk samples being submitted for bacteriological culture and SCC determination. PCR amplification of the internal transcribed spacer region and sequencing of the sodA and rpoB genes were used for species allocation. Pulsed-field gel electrophoresis (PFGE) was performed to assess strain identity. The percentage of quarters affected per farm varied between 6 and 35%, with the most frequently isolated CNS species being Staphylococcus epidermidis, followed by Staph. simulans, Staph. chromogenes and Staph. haemolyticus. It was possible to follow 111 intramammary infections due to CNS through time. Duration of infection had a mean of 188 d and was not significantly different between CNS species. Geometric mean quarter SCC overall was 132 000 cells/ml and was also not significantly different between CNS species. Despite the possibility of a different epidemiology of infection, the impact in terms of udder health seems to be similar for different CNS species.

Virulence traits and antibiotic resistance among enterococci isolated from Eurasian otter (Lutra lutra).

Enterococci are ubiquitous microorganisms found as part of the normal intestinal microbiota of many animals such as the free-ranging Eurasian otter (Lutra lutra Linnaeus, 1758). In this work, twenty-nine enterococci isolated from fecal samples of Eurasian otters free-living in reservoirs and associated river stretches in South Portugal were identified and typed by conventional/molecular methods and screened for virulence factors and antibiotic resistance. Identification allocated the isolates to the species Enterococcus faecalis (19), E. faecium (9) and E. durans (1) and PCR-fingerprinting revealed their high genomic diversity. Regarding virulence factors, three isolates produced cytolysin and six were gelatinase-positive. Genes ace and acm were detected in five enterococci each, ebpABC in seventeen, gelE in fourteen and cylA in three. All isolates showed resistance patterns and antibiotic resistance genes tet(M) and pbp5 were detected in seventeen isolates each, whereas vanB and vanD were identified in thirteen and five, respectively, being most van-harboring isolates members of E. faecium. The aac(6')-Ie-aph (2″) gene, encoding for gentamicin resistance, was observed in all gentamicin-resistant enterococci. Since all isolates harbor virulence and/or antibiotic resistance traits, the role of free-living Eurasian otters in the dissemination of virulent/resistant enterococci among other animals sharing the same ecological niche cannot be disregarded, as well as the health risk they may represent for humans directly interacting with them or their habitat.