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Copyright of Pesquisa Veterinaria Brasileira is the property of Colegio Brasileiro de Patologia Animal - CBPA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Pesquisa Veterinaria Brasileira is the property of Colegio Brasileiro de Patologia Animal - CBPA and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article discusses a study on the classification of the antimicrobial resistance of avian pathogenic Escherichia coli (APEC) specimens in broiler chicken samples, using artificial neural networks (ANNs) to analyse 38 virulence factor-related genes in E. coli.

The article presents a study on the detection of virulence-associated genes in Salmonella enteritidis isolates from chicken in South of Brazil. The detection process based on polymerase chain reaction (PCR) assays done on 84 isolates found four different groups of genetic profiles named P1, P2, P3 and P4 with P1 as the most prevalent being present in 88% of the isolates. By determining the virulence profile of these genes it reportedly may help predict the virulence of different strains.

The article presents a study which investigated the 12 genes associated with virulence in 25 samples of Pasteurella multocida in Brazil. Researchers found several genes including nanB, exBD-tonB and hgbB genes to be present in all of the samples. Another key finding of the study is that the ptfA is present in 92 per cent of the samples while the pfhA was seen in 60 per cent of the samples. Researchers concluded that multiplex polymerase chain reaction (PCR) is an effective tool in detecting the presence of the genes in the samples.

The article focuses on a study which evaluated follicular lymphoid depletion in the Bursa of Fabricius (BF), an alternative using digital media analysis and artificial neural networks (ANN). Using Neuroshell Classifier software, the ANN was generated and the optical and digital data were compared. Majority of the follicles were classified correctly using the ANN, reaching sensibility and specificity of 89% and 96%, respectively. Study results indicate that the use of digital image analysis and ANN is a useful tool for the pathological classification of the BF lymphoid depletion.

Eight hundred skin samples from broiler carcasses condemned or downgraded for skin lesions were collected at five processing plants. Histologically, 45.25% were cellulitis, 19.00% were atypical fowlpox, 3.25% were dermal squamous cell carcinoma (DSCC), 17.00% were non-specific dermatitis, 0.5% were focal haemorrhages and 0.25% were haemangiomas. Of the samples, 14.75% were histologically normal. Macroscopically, increased thickening of the skin was a frequent finding occurring in all the skin diseases, as well as skin discoloration, dark nodules in feather follicles and crusts. Skin scratches were associated with all of the diseases, except DSCC. Crater-like ulcers occurred in DSCC and fowlpox. Cellulitis was more frequent on the abdomen, fowlpox on the dorsum, DSCC in thighs, and non-specific dermatitis on the dorsum, thighs, legs and breast. It was concluded that macroscopic changes are not specific and examinations at slaughterhouses do not allow classification of broiler skin diseases. Histological examination appears to be an important tool to provide more accurate data. [ABSTRACT FROM AUTHOR]

Campylobacteriosis is one of the most common types of bacterial gastroenteritis affecting humans, and poultry is considered a major source of the causative organism, Campylobacter spp. Broilers may arrive contaminated at slaughterhouses, and transport crates could be considered a potential source of contamination. Thus, cleaning and disinfection procedures are crucial to avoid cross-contamination among flocks. Despite its public health importance in Latin American countries, virulence factors of Campylobacter jejuni remain poorly studied in this region. Thus, this study aimed to: 1) determine the occurrence of contaminated crates at a poultry slaughterhouse, 2) compare the contamination before and after the cleaning and disinfection procedures, and 3) detect virulence-associated genes in C. jejuni strains by PCR. Campylobacter spp. were recovered from 8 of the 10 flocks evaluated, and C. jejuni was detected as the main species. There was no significant difference in the Campylobacter detection or quantification between crates at the reception platform and crates after the cleaning/disinfection processes. However, crates after 24 h of natural drying, presented a significant (P < 0.05) lower amount of Campylobacter cells than before the cleaning and disinfection processes. A negative relationship (R 2  = 0.210, P = 0.045) between environmental conditions and Campylobacter quantification was found for transport crates after 24 h of natural drying. There was no significant difference (P > 0.05) in the detection of two C. jejuni virulence genes, flaA (encode a major flagellin protein) and cadF (encode an adhesion and fibronectin-binding protein), among various stages of the cleaning and disinfection processes. Our results demonstrate the high contamination levels of Campylobacter strains in broiler flocks and the potential involvement of poultry transport crates in transmitting these bacteria. This study also suggests that ineffective cleaning and disinfection procedures can increase Campylobacter contamination and facilitate the spread of bacteria in poultry establishments., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Brazil is the number one exporter of chicken meat, and this industry maintains constant microbiological vigilance. The objective of this study was to characterize the pathogenicity, antimicrobial resistance (AMR) and the profile of biofilm production of Escherchia coli strains isolated from raw refrigerated cuts of chicken meat sold in retail markets of the four largest poultry companies in Brazil. We collected 150 samples of chicken meat, in order to isolate E. coli and performed susceptibility tests (to amoxicillin associated with clavulanic acid, ceftiofur, enrofloxacin, gentamicin, and trimethoprim + sulfamethoxazole). In addition, the disc approximation test to detect extended spectrum beta-lactamases enzymes (ESBLs) producers was performed. E. coli ability to form biofilm was checked using polystyrene microplates. We also searched for ESBLs genes (blaCTY-M2, blaSHV-1, blaTEM-1, blaCTX-M2, blaOXA-1, blaPSE-1 and AmpC) and adhesion genes (sfa/foc, afa/draB, iha, hrla, fimC, tsh, papC, mat, cr1, felA, fimH and papG) in ESBL-E. coli producers and in those E. coli classified as strongly biofilm formers, respectively. The overall percentage of E. coli isolation was 58.66%, with brand A having the highest percentage (70%), followed by brands D, B and C (60, 53.3 and 50%, respectively). The highest resistance profile was observed for beta-lactams (39.5%), followed by sulfonamide associated to trimethoprim (36.9%) and polymyxin (33.4%). Of the isolates obtained, 77% were non-susceptible to at least one antimicrobial. Brand A showed the highest overall percentage of resistance with 95.23%, followed by brands C (80%), B (75%) and D (69.44%). Overall, 73.86% of the isolates were non susceptible to at least one antibiotic and 36.3% were multiresistants. A total of 17.04% of E. coli strains were identified as ESBLs producers and 70.44% were able to form biofilms (moderate-to-strong). The blaTEM-1 gene was the most prevalent (73.33%), followed by blaSHV-1 (46.66%) and blaCMY-2 (6%). Of the 31 strongly biofilm-forming strains, 26 (83.87%), 24 (77.41%) and 20 (64.51%) expressed fimC, papG and crl genes, respectively. Taken together, our results show that Brazilian chicken meat can be contaminated with E. coli that are non-susceptible to multiple antibiotics, able to form biofilm and showing a diverse repertoire of adhesins linked to pathogenicity depending on the brand evaluated., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)