Respiratory microbiota of healthy broilers can act as reservoirs for multidrug-resistant Escherichia coli.

This study aimed at evaluate the presence and to study characteristics of Escherichia coli in the respiratory system microbiota of healthy broilers. Trachea, air sacs, and lungs of 20 broilers were analyzed at 21 days of age, reared in experimental conditions, without receiving antimicrobials. E. coli strains were isolated and identified using conventional bacteriology through morphological and biochemical characterization. The production of bacteriocin-like substances, the presence of virulence-associated genes (VAGs) of APEC (Avian Pathogenic Escherichia coli) predictors, and the antimicrobial susceptibility were evaluated. E. coli was found in 85 % of the animals (17/20), in the trachea, air sacs or lungs; and it was not found in 15 % of the animals (3/20). A total of 34 isolates were recovered, 13 from the air sacs, 13 from the lungs, and 8 from the trachea, which showed no production of bacteriocin-like substances nor virulence genes associated with APEC. Most isolates, 59 % (20/34), showed resistance to at least one of the tested antimicrobials, and six multiresistant strains were identified. The results demonstrated that strains of E. coli were commensal of the respiratory microbiota, and that they did not present pathogenicity to the host, since there were no clinical signs of disease, macroscopic lesions in the organs of the evaluated broilers, production of bacteriocin-like substances, nor virulence-associated genes considered as predictors of APEC in bacteria. These strains of E. coli were mostly susceptible to antimicrobials. However, the occurrence of multidrug-resistant strains suggests that these animals can act as reservoirs of resistant to antimicrobials E. coli.

Occurrence of genes associated with virulence in Escherichia coli isolates from chicken carcasses at different stages of processing at a slaughterhouse.

Escherichia coli is a bacterium frequently found in chicken carcasses, causing carcass condemnation with losses to the industry and when present in food, it carries a risk to public health as there is evidence that some strains pathogenic to birds (APEC - Avian Pathogenic E. coli) have zoonotic potential. Carcass contamination can occur at the slaughterhouse, but the influence of the different stages of processing in the selection of potential extraintestinal pathogenic E. coli strains is unknown. This study aimed to analyze the influence of the processing steps in the slaughterhouse on the detection of E. coli isolates carrying APEC predictor's virulence-associated genes (VAGs), and to relate their presence with post-mortem condemnation. A sample consisted of four pooled carcasses collected at seven different stages of slaughter (before scalding, after scalding, after plucking, before evisceration/after shower wash, after evisceration, after pre-coolers, and after packing) from 15 batches of broilers. The total samples obtained was 105 pools with four carcasses each, totaling 420 carcasses analyzed. Enterobacteriaceae were counted from each pool and E. coli were subsequently selected, which were submitted to pentaplex PCR to identify the five VAG APEC predictor's: iroN, ompT, hlyF, iss, and iutA. The Enterobacteriaceae count demonstrated a reduction of 4.25 log CFU per gram of carcass from the first to the last stage analyzed, with scalding and pre-cooling by immersion being the procedures that contributed most to this reduction. The presence of VAGs and potential APEC (presence of two or more of these gene predictors) was observed at all points evaluated in the slaughterhouse, which suggested that bacteria carrying these genes could reach the consumer.

Antimicrobials and resistant bacteria in global fish farming and the possible risk for public health / Antimicrobianos e bactérias resistentes na piscicultura global e o possível risco para a saúde pública

The use of antimicrobials in fish farming is a reflection of the fast aquaculture development worldwide. The intensification of aquaculture to achieve market demands could lead to an increase in infectious diseases by pathogenic bacteria. Consequently, antimicrobials act as controls for emerging infectious diseases, but their use must follow the rules and regulations of the country where the activity is performed. Although the regulations impose limits to the use of antimicrobials in fish farming, many studies show that resistant bacteria are isolated from this system. The selection of resistant bacteria is not limited only to the use of antimicrobials, but also to co-selection of resistance genes or even with cross-resistance processes. Resistant bacteria from fish farming are a serious concern because they can be acquired by humans with handling or food chain, which may represent a public health problem. In the present review, we present an overview of antimicrobials use in aquaculture, the antimicrobial resistance and the impact of antimicrobial and bacterial resistance from a public health perspective.(AU)

O uso de antimicrobianos na piscicultura é um reflexo do rápido desenvolvimento da aquicultura em todo o mundo. A intensificação da aquicultura para suprir as demandas do mercado pode levar ao aumento de doenças infecciosas por bactérias patogênicas. Consequentemente, os antimicrobianos atuam no controle de doenças infecciosas emergentes, mas seu uso deve seguir as regras e regulamentos do país onde a atividade é realizada. Embora os regulamentos imponham limites ao uso de antimicrobianos na piscicultura, muitos estudos mostram que bactérias resistentes são isoladas desse sistema. A seleção de bactérias resistentes não se limita apenas ao uso de antimicrobianos, mas também à cosseleção de genes de resistência ou mesmo por meio do processo de resistência cruzada. As bactérias resistentes da piscicultura são uma preocupação séria, uma vez que tais bactérias podem ser adquiridas pelos seres humanos no manuseio ou na cadeia alimentar, o que pode representar um problema de saúde pública. Nesta revisão, apresentamos uma visão geral do uso de antimicrobianos na aquicultura, a resistência antimicrobiana e o impacto da resistência antimicrobiana e bacteriana do ponto de vista da saúde pública.(AU)

An Online Survey of Occupational Hazards in Brazilian Aquaculture.

Information on occupational health and safety practices in Brazilian aquaculture is limited. This paper reports preliminary results from an online survey based on research questions to identify occupational hazards, risk assessment practices, and prevention measures adopted in Brazilian aquaculture. Data were collected through an online questionnaire, comprising 25 questions, on a voluntary and anonymous basis. Aquaculture stakeholders were invited to participate in the study through email and social media channels. The demographic data demonstrated that the majority of respondents were men (72%) and having a higher education (95%). Most respondents employed administrative controls and personal protective equipment (PPE) rather than substitution and other risk elimination measures to reduce exposure. The most commonly adopted measures were PPE use (87%), adequate handling of chemicals (86%), and imparting knowledge of risks (90%). However, only 12% of participants reported the presence of safety protocols at their workplace, and 17% had some form of immunization of workers. In this study, it was possible to identify a lack of hazard signage in the workplace and lack of occupational health and safety training. The results further indicate that risk management in aquaculture continues to be a challenge in low-income countries. Aquaculture farmers should be encouraged and supported in adopting measures and appropriate technologies to eliminate risks in Brazilian aquaculture.

Occupational Health and Safety in Aquaculture: Insights on Brazilian Public Policies.

Aquaculture has many occupational hazards, including those that are physical, chemical, biological, ergonomic, and mechanical. The risks in aquaculture are inherent, as this activity requires particular practices. The objective of the present study was to show the risks associated with the aquaculture sector and present a critical overview on the Brazilian public policies concerning aquaculture occupational health. Methods include online research involved web searches and electronic databases including Pubmed, Google Scholar, Scielo and government databases. We conducted a careful revision of Brazilian labor laws related to occupational health and safety, rural workers, and aquaculture. The results and conclusion support the idea that aquaculture requires specific and well-established industry programs and policies, especially in developing countries. Aquaculture still lacks scientific research, strategies, laws, and public policies to boost the sector with regard to occupational health and safety. The establishment of a safe workplace in aquaculture in developing countries remains a challenge for all involved in employer-employee relationships.

Aplicação da técnica de RT-PCR para metapneumovírus aviário (aMPV) / Application of RT-PCR technique for avian metapneumovirus (aMPV) / Aplicación de la técnica RT-PCR para metapneumovirus aviario (aMPV)

Os principais hospedeiros do Metapneumovírus aviário (aMPV) são os frangos de corte e perus. O vírus acomete o trato respiratório superior dos perus desencadeando a Rinotraqueíte Viral dos Perus (RVP). O principal objetivo deste trabalho foi padronizar uma técnica de RT-PCR para a detecção do aMPV, por meio do uso do kit AccessQuick™ RT-PCR system (Promega®). Foram utilizados amostras de suabes de traqueia e pulmão de 38 perus comerciais com sintomatologia respiratória e dois suabes oculares de faisão. O RNA viral foi extraído utilizando-se o kit RTP® DNA/RNA Virus Mini Kit (STRATEC Molecular). Em seguida as amostras foram submetidas à RT-PCR One Step, utilizando o kit AccessQuick™ RT-PCR system (Promega®). Todas as 40 amostras testadas por RT-PCR foram negativas, exceto a amostra vacinal que foi utilizada como controle positivo. O aMPV não causa latência em frangos de corte ou perus, logo a excreção viral é limitada. Dessa forma, a ausência da detecção de genoma viral neste estudo pode ser justificada devido à idade que as amostras foram coletadas em perus, com 140 dias no abatedouro, impossibilitando dessa maneira a amplificação do genoma do aMPV. Porém, esse estudo também mostra que a RT-PCR se mostrou eficaz para detectar o genoma viral do aMPV, podendo dessa forma ser utilizado como uma ferramenta de diagnóstico rápido para investigação e estudo de casos de aMPV em rebanho de perus.

The main hosts of Avian metapneumovirus (aMPV) are broilers and turkeys. This virus affects the upper respiratory tract of turkeys, triggering Turkey Rhinotracheitis (TRT). The aim of this study was to optimize a RT-PCR technique in order to detect aMPV using the AccessQuick™ RT-PCR system (Promega®) kit. Tracheal and lung swab samples from 38 commercial turkeys with respiratory symptoms and two ocular swabs from pheasants were analyzed. Viral RNA was extracted using RTP® DNA/RNA Virus Mini Kit (Molecular STRATEC) kit. All 40 samples tested were negative in the RT-PCR. The only positive sample was a vaccine strain, used as the positive control. The aMPV does not cause latency in broilers, chickens or turkeys, thus, the viral excretion is limited. However, the absence of viral genome detection in this study may be justified due to the age the samples were collected, since they were collected in turkeys with about 140 days in the slaughterhouse, thus preventing the amplification of the aMPV genome. This study shows that the RT-PCR is effective to detect aMPV viral genome and may be used as a rapid diagnostic tool for research and for the studying of aMPV cases in turkey flocks in Brazil.

Los principales anfitriones de Metapneumovirus aviario (aMPV) son los pollos de engorde y pavos. El virus afecta el tracto respiratorio superior de los pavos desencadenando la Rinotraqueitis Viral de los pavos (RVP). El principal objetivo de ese estudio fue estandarizar una técnica de RT-PCR para la detección del aMPV, a través del uso del kit AccessQuick™-PCRsystem (Promega®). Se utilizaron muestras de hisopos traqueales y pulmonares de 38 pavos comerciales con síntomas respiratorios y dos hisopos oculares de faisán. El RNA viral se extrajo utilizando el kit DNA RTP® DNA/RNA Virus Mini Kit (STRATEC Molecular). A continuación, las muestras se sometieron a la RT-PCR OneStep utilizando el kit AccessQuick™ RT-PCR (Promega®). Todas las 40 muestras analizadas por RT-PCR fueron negativas, excepto la muestra de vacuna que se utilizó como control positivo. El aMPV no causa latencia en pollos de engorde o pavos, por lo que la excreción viral es limitada. Así, la ausencia de la detección de genoma viral en este estudio puede ser justificada debido a la edad que se recogieron las muestras en los pavos, con 140 días en el matadero, imposibilitando de este modo la amplificación del genoma del aMPV. Sin embargo, ese estudio también muestra que la RT-PCR se ha demostrado eficaz para detectar el genoma viral del aMPV, pudiendo así ser utilizado como una herramienta de diagnóstico rápido para investigación y estudio de casos de aMPV en bandada de pavos.

Natural occurrence of White spot syndrome virus and Infectious hypodermal and hematopoietic necrosis virus in Neohelice granulata crab.

White spot syndrome virus (WSSV) and Infectious hypodermal and hematopoietic necrosis virus (IHHNV) are two infectious agents associated to economic losses in shrimp aquaculture. As virus spread occurs through vectors and hosts, this study sought to verify the presence of WSSV and IHHNV in Neohelice granulata crab from Lagoa dos Patos estuary in Brazil and nearby shrimp farms. DNA extractions were performed with phenol/chloroform protocol. Molecular diagnosis was carried out by nested PCR for WSSV and one-step PCR for IHHNV. Results showed the presence of WSSV on crabs of both Lagoa dos Patos and farms, while IHHNV was found only on crabs collected in estuary. This is the first study to report IHHNV presence in N. granulata. Moreover, as analyzed crabs had no clinical symptoms or showed in situ mortality, we suggest its use as a bioindicator for virus occurrence in aquatic environments.

First report of White spot syndrome virus in farmed and wild penaeid shrimp from Lagoa dos Patos estuary, southern Brazil

In this study, we detected White spot syndrome virus (WSSV) in wild Farfantepenaeus paulensis collected in the Lagoa dos Patos estuary and cultivated Litopenaeus vannamei. This is the first report of WSSV in F. paulensis from Lagoa dos Patos and farmed L. vannamei shrimps in Rio Grande do Sul.

First report of White spot syndrome virus in farmed and wild penaeid shrimp from lagoa dos patos estuary, southern brazil.

In this study, we detected White spot syndrome virus (WSSV) in wild Farfantepenaeus paulensis collected in the Lagoa dos Patos estuary and cultivated Litopenaeus vannamei. This is the first report of WSSV in F. paulensis from Lagoa dos Patos and farmed L. vannamei shrimps in Rio Grande do Sul.