Detection of virulence-associated genes in pathogenic and commensal avian Escherichia coli isolates

Poultry colibacillosis due to Avian Pathogenic Escherichia coli (APEC) is responsible for several extra-intestinal pathological conditions, leading to serious economic damage in poultry production. The most commonly associated pathologies are airsacculitis, colisepticemia, and cellulitis in broiler chickens, and salpingitis and peritonitis in broiler breeders. In this work a total of 66 strains isolated from dead broiler breeders affected with colibacillosis and 61 strains from healthy broilers were studied. Strains from broiler breeders were typified with serogroups O2, O18, and O78, which are mainly associated with disease. The serogroup O78 was the most prevalent (58%). All the strains were checked for the presence of 11 virulence genes: 1) arginine succinyltransferase A (astA); ii) E. coli hemeutilization protein A (chuA); iii) colicin V A/B (cvaA/B); iv) fimbriae mannose-binding type 1 (fimC); v) ferric yersiniabactin uptake A (fyuA); vi) iron-repressible high-molecular-weight proteins 2 (irp2); vii) increased serum survival (iss); viii) iron-uptake systems of E. coli D (iucD); ix) pielonefritis associated to pili C (papC); x) temperature sensitive haemaglutinin (tsh), and xi) vacuolating autotransporter toxin (vat), by Multiplex-PCR. The results showed that all genes are present in both commensal and pathogenic E. coli strains. The iron uptake-related genes and the serum survival gene were more prevalent among APEC. The adhesin genes, except tsh, and the toxin genes, except astA, were also more prevalent among APEC isolates. Except for astA and tsh, APEC strains harbored the majority of the virulence-associated genes studied and fimC was the most prevalent gene, detected in 96.97 and 88.52% of APEC and AFEC strains, respectively. Possession of more than one iron transport system seems to play an important role on APEC survival.

Establishment of antibody panels and histochemical techniques in routine tumor diagnosis in Veterinary Pathology

In Portugal, Veterinary Pathology is developing rapidly, and in recent years we assist to the emergence of private laboratories and the restructuring of universities,polytechnics and public laboratories.The Portuguese Society of Animal Pathology,through its actions and its associates has been keeping the discussion among its peers in order to standardizethe criteria of description,classification and evaluation of cases which are the subject of our daily work.One of the last challenges is associated with the use of routine histochemical techniques and immunohistochemistry, in an effort to establish standardized panels for tumour diagnosis, which could eventually reduce each analysis cost.For this purpose a simple survey was built, in which all collaborators answered questions about the markers used for carcinoma, sarcoma and round cell tumour diagnosis, as well as general questions related with the subject. We obtained twenty-one answered to the questions, from public and private laboratories.In general, in most cases immunohistochemical and histochemical methods are used for diagnosis.The wide spectrum cytokeratins are universally used to confirm carcinoma, and vimentin for sarcoma. The CD3 marker is used by all laboratories to identify T lymphocytes. For the diagnosis of B-cell lymphoma, the marker used is not consensual. In each laboratory there are different markers for more specific situations and only two labs perform PCR techniques for diagnosis. These data will be presented to promote extended discussion,namely to reach a consensus when different markers are used.

Avian trait-mediated vulnerability to road traffic collisions

Collision with vehicles is an important source of bird mortality, but it is uncertain why some species are killed more often than others. Focusing on passerines,we testedwhether mortality is associated with bird abundances, and with traits reflecting flight manoeuvrability, habitat, diet, and foraging and social behaviours. We also tested whether the species most vulnerable to road-killing were scarcer near (b500 m) or far (N500–5000 m) from roads. During the breeding seasons of 2009–2011,we surveyed roadkills daily along 50 km of roads, and estimated bird abundances from 74 point counts. After correcting for phylogenetic relatedness, there was strong correlation between roadkill numbers and the abundances of 28 species counted near roads. However, selectivity indices indicated that Blue tit (Parus caeruleus), Blackcap (Sylvia atricapilla) and European goldfinch (Carduelis carduelis) were significantly more road-killed than expected from their abundances, while the inverse was found for seven species. Using phylogenetic generalised estimating equations, we found that selectivity indexes were strongly related to foraging behaviour and habitat type, and weakly so to body size, wing load, diet and social behaviour. The most vulnerable passerines were foliage/bark and swoop foragers, inhabiting woodlands, with small body size and low wing load. The species most vulnerable to road collisions were not scarcer close to roads. Overall, our study suggests that traits provide a basis to identify the passerine species most vulnerable to road collisions, which may be priority targets for future research on the population-level effects of roadkills.