Detection of adenovirus, rotavirus, and hepatitis E virus in meat cuts marketed in Uruguaiana, Rio Grande do Sul, Brazil.

The aim of this study was to investigate the presence of adenovirus (AdV), rotavirus (RV), and hepatitis E virus (HEV) in beef, pork, and chicken meat cuts in retail trade in the city of Uruguaiana, RS, Brazil. A total of 131 meat products were collected (beef, n = 55; chicken, n = 47; pork, n = 29) from 18 commercial establishments (supermarkets, n = 7; butchers, n = 7; markets/grocery stores, n = 4). All samples were evaluated for AdV, RV, and HEV. The genomes of RV and AdV were identified in 29% (n = 38) and 5.34% (n = 7) of the samples, respectively. HEV was not identified in any of the samples. Chicken cuts had a higher frequency of AdV and RV isolates compared to beef and pork (P < 0.05). Among the categories of commercial establishments evaluated, all revealed at least one positive sample for AdV and RV; however, supermarkets showed a higher frequency of RV than others (P < 0.05). The genetic material of AdV and RV was identified simultaneously in 2.29% (n = 3) of samples from supermarkets (n = 2) and grocery stores (n = 1). This is the first report on detection of enteric viruses in meat cuts in the western region of the state of Rio Grande do Sul, Brazil, and the presence of AdV and RV in these products may indicate flaws during the process of handling these foods, especially in places where commercialization provides important public health issues.

Identification of Salmonella spp., Listeria monocytogenes, and indicator microorganisms in commercialized raw meats and fresh sausages from Uruguaiana, Rio Grande do Sul, Brazil / Identificação de Salmonella spp., Listeria monocytogenes e micro-organismos indicadores em carnes cruas e embutidos frescais comercializados na cidade de Uruguaiana, Rio Grande do Sul, Brasil

ABSTRACT: This study evaluated the sanitary hygienic quality and the presence of pathogenic microorganisms in raw meats and fresh sausages marketed in the city of Uruguaiana, Rio Grande do Sul (RS), Brazil. We analyzed 238 samples of fresh sausages, beef, pork, and chicken from 18 commercial establishments (butchers, supermarkets, and groceries). Samples were subjected to enumerate hygiene indicator microorganisms (mesophilic aerobes and enterobacteria) and detection of Salmonella spp. and Listeria monocytogenes. The mean counts of mesophilic aerobes and enterobacteria were 5.09 and 3.54 log CFU/g, respectively. Beef samples presented the highest frequency of Salmonella spp. (7.93%) and fresh sausages present the highest frequency of L. monocytogenes (19.04%). Among the analyzed samples, 43.70% did not comply with the microbiological parameters established by the Brazilian Ministry of Health. The presence of Salmonella spp. and L. monocytogenes in different samples and commercial establishments demonstrate the failures of good manufacturing practices in industrial environmental and retails points and the need to train food handlers to reduce the exposure of consumers to potential risks.

RESUMO: Este estudo teve como objetivo avaliar a qualidade higiênica sanitária e a presença de microrganismos patogênicos em carnes in natura e linguiças frescais comercializadas na cidade de Uruguaiana, Rio Grande do Sul (RS), Brasil. Foram analisadas 238 amostras de linguiças, carne bovina, suína e de frango de 18 estabelecimentos comerciais (açougues, supermercados e mercearias). As amostras foram submetidas à enumeração de microrganismos indicadores de higiene (aeróbios mesófilos e enterobactérias) e detecção de Salmonella spp. e Listeria monocytogenes. As contagens médias de aeróbios mesófilos e enterobactérias foram 5,09 e 3,54 log UFC/g, respectivamente. Salmonella spp. esteve presente mais frequentemente em amostras de carne bovina (4,91 %), enquanto L. monocytogenes foi mais frequente em linguiças frescais (19,04 %). Das amostras analisadas, 43,70 % não atenderam aos parâmetros microbiológicos estabelecidos pelo Ministério da Saúde. A presença de Salmonella spp. e L. monocytogenes em diferentes amostras e estabelecimentos comerciais demonstra falhas de boas práticas de fabricação na indústria e pontos de venda, além da necessidade de treinar manipuladores de alimentos para reduzir a exposição dos consumidores à riscos.

Actinobacillus pleuropneumoniae culture supernatant antiviral effect against porcine reproductive and respiratory syndrome virus occurs prior to the viral genome replication and transcription through actin depolymerization.

PURPOSE: Recently, the strong antiviral activity of an Actinobacillus pleuropneumoniae (App) culture supernatant against porcine reproductive and respiratory syndrome virus (PRRSV) was discovered. Following this finding, the objective of the present study was to understand how the App culture supernatant inhibits PRRSV replication in its natural targeted host cells, i.e. porcine alveolar macrophages (PAMs). METHODOLOGY: Several assays were conducted with App culture supernatant-treated PRRSV-infected cell lines, such as PAM, St-Jude porcine lung and MARC-145 cells. RT-qPCR assays were used to determine the expression levels of type I and II IFN mRNAs, viral genomic (gRNA) and sub-genomic RNAs (sgRNAs). Proteomic, Western blot and immunofluorescence assays were conducted to determine the involvement of actin filaments in the App culture supernatant antiviral effect.Results/Key findings. Type I and II IFN mRNA expressions were not upregulated by the App culture supernatant. Time courses of gRNA and sgRNA expression levels demonstrated that the App culture supernatant inhibits PRRSV infection before the first viral transcription cycle. Western blot experiments confirmed an increase in the expression of cofilin (actin cytoskeleton dynamics regulator) and immunofluorescence also demonstrated a significant decrease of actin filaments in App culture supernatant-treated PRRSV-infected PAM cells. App culture supernatant antiviral activity was also demonstrated against other PRRSV strains of genotypes I and II. CONCLUSION: App culture supernatant antiviral effect against PRRSV takes place early during PRRSV infection. Results suggest that App culture supernatant antiviral effect may take place via the activation of cofilin, which induces actin depolymerization and subsequently, probably affects PRRSV endocytosis. Other experiments are needed to fully validate this latest hypothesis.

Whole Genome Sequencing of a Canadian Bovine Gammaherpesvirus 4 Strain and the Possible Link between the Viral Infection and Respiratory and Reproductive Clinical Manifestations in Dairy Cattle.

Bovine gammaherpesvirus 4 (BoHV-4) is a herpesvirus widespread in cattle populations, and with no clear disease association. Its genome contains a long unique coding region (LUR) flanked by polyrepetitive DNA and 79 open reading frames (ORFs), with unique 17 ORFs, named Bo1 to Bo17. In 2009, a BoHV-4 strain was isolated (FMV09-1180503: BoHV-4-FMV) from cattle with respiratory disease from Quebec, Canada, and its LUR was sequenced. Despite the overall high similarity, BoHV-4-FMV had the most divergent LUR sequence compared to the two known BoHV-4 reference strain genomes; most of the divergences were in the Bo genes and in the repeat regions. Our phylogenetic analysis based on DNA polymerase and thymidine kinase genes revealed that virus isolate was BoHV-4 gammaherpesvirus and clustered it together with European BoHV-4 strains. Because BoHV-4-FMV was isolated from animals presenting respiratory signs, we have updated the BoHV-4 Canadian cattle seroprevalence data and tried to find out whether there is a link between clinical manifestation and BoHV-4 seropositivity. An indirect immunofluorescence assay (IFA) was performed with nearly 200 randomized sera of dairy cattle from two Canadian provinces, Quebec (n = 100) and Ontario (n = 91). An additional set of sera obtained from Quebec, from the healthy (n = 48) cows or from the animals experiencing respiratory or reproductive problems (n = 75), was also analyzed by IFA. BoHV-4 seroprevalence in Canadian dairy cattle was 7.9% (Quebec: 6% and Ontario: 9.9%). Among animals from the Quebec-based farms, diseased animals showed higher BoHV-4 seropositivity than healthy animals (P < 0.05), with a significant 2.494 odds ratio of being seropositive in sick compared to healthy animals. Although there is no established direct link between BoHV-4 and specific diseases, these seroprevalence data suggest the possible involvement of BoHV-4 in dairy cattle diseases.

Genetic diversity of 3' region of glycoprotein D gene of bovine herpesvirus 1 and 5.

Bovine herpesviruses 1 (BoHV-1) and 5 (BoHV-5) are closely related alphaherpesviruses of cattle. While BoHV-1 is mainly associated with respiratory/genital disease and rarely associated with neurological disease, BoHV-5 is the primary agent of meningoencephalitis in cattle. The envelope glycoprotein D of alphaherpesviruses (BoHV-1/gD1 and BoHV-5/gD5) is involved in the early steps of virus infection and may influence virus tropism and neuropathogenesis. This study performed a sequence analysis of the 3' region of gD gene (gD3') of BoHV-1 isolates recovered from respiratory/genital disease (n = 6 and reference strain Cooper) or from neurological disease (n = 7); and from seven typical neurological BoHV-5 isolates. After PCR amplification, nucleotide (nt) sequencing, and aminoacid (aa) sequence prediction; gD3' sequences were compared, identity levels were calculated, and selective pressure was analyzed. The phylogenetic reconstruction based on nt and aa sequences allowed for a clear differentiation of BoHV-1 (n = 14) and BoHV-5 (n = 7) clusters. The seven BoHV-1 isolates from neurological disease are grouped within the BoHV-1 branch. A consistent alignment of 346 nt revealed a high similarity within each viral species (gD1 = 98.3 % nt and aa; gD5 = 97.8 % nt and 85.8 % aa) and an expected lower similarity between gD1 and gD5 (73.7 and 64.1 %, nt and aa, respectively). The analysis of molecular evolution revealed an average negative selection at gD3'. Thus, the phylogeny and similarity levels allowed for differentiation of BoHV-1 and BoHV-5 species, but not further division in subspecies. Sequence analysis did not allow for the identification of genetic differences in gD3' potentially associated with the respective clinical/pathological phenotypes, yet revealed a lower level of gD3' conservation than previously reported.

Nucleotide sequencing and phylogenetic analysis of the 3' region of glycoprotein C gene of South American bovine herpesviruses 1 and 5.

We herein describe a molecular analysis based on the 3' region of the glycoprotein C gene of 45 bovine herpesvirus (BoHV) isolates from Brazil (n=41), Uruguay (n=2) and Argentina (n=2). Nucleotide (nt) sequencing and alignment of 333 nt revealed levels of similarity ranging from 99.1% to 100% among BoHV-1 sequences (n=12); 96.2-100% among BoHV-5 sequences (n=32); and 77.7-90.3% between BoHV-1 and BoHV-5 sequences. The phylogenetic tree reconstruction provided a clear distinction between BoHV-1 and BoHV-5, and BoHV-1 into subtypes BoHV-1.1 and BoHV-1.2. The isolate SV 453/93 (BoHV-1 associated with genital disease) could not be included within BoHV-1 subtypes since it presented a markedly distinct nt and amino acid (aa) deduced sequences. A transmembrane domain of 24 aa and the putative cytoplasmic tail of 8 aa were identified and mapped. These results indicate that this genome region represents a suitable target for phylogenetic subgrouping of BoHV-1 and BoHV-5 isolates and, perhaps, for understanding evolutionary relationships.

Óleos essenciais como substituintes de antibióticos promotores de crescimento em frangos de corte: perfil de soroproteínas e peroxidação lipídica / Essential oils as substitutes for antibiotic growth promoters in broilers: soroproteins profile and lipid peroxidation

Os óleos essenciais são alternativas ao uso de promotores de crescimento antibióticos na avicultura, devido à sua ação antimicrobiana, além de possuírem propriedades antioxidante e imunomoduladora. Este estudo foi realizado com o objetivo de avaliar o efeito da suplementação dietética de três doses de óleos essenciais (OLES) de orégano (Origanum vulgare L.), sálvia (Salvia officinalis L.), alecrim (Rosmarinus officinalis L.) e extrato de pimenta (Capsicum frutescens L.) em frangos de corte, pela análise do perfil eletroforético de soroproteínas e da peroxidação lipídica plasmática. Os animais (n=910) foram alocados de forma aleatória em cinco tratamentos, com sete repetições de 26 aves cada: o grupo controle (Tc), que recebeu dieta basal sem aditivos; o grupo que recebeu promotor de crescimento antibiótico na dieta (Tatb); e os grupos T50, T100 e T150, alimentados com OLES na doses de 50, 100 e 150mg kg-1, respectivamente. Aos 42 dias de idade, sete animais foram aleatoriamente selecionados (um de cada repetição) para o estudo do perfil eletroforético de soroproteínas e para a avaliação da peroxidação plasmática de lipídeos, pelo teste de formação de substâncias reativas ao ácido tiobarbitúrico (TBARS). Houve diminuição na concentração de globulinas totais no T150 e na fração betaglobulina nos grupos Tatb e T150 em relação ao grupo controle e ao T50 (P<0,05). Além disso, os níveis de TBARS plasmático foram menores nos grupos que receberam OLES em comparação ao Tc (P<0,05). Dessa forma, pode-se inferir que o efeito dos OLES, na maior dose administrada, sugere menor estímulo ao sistema inume humoral de frangos de corte, assim como acontece com a suplementação de promotores de crescimento antibióticos. Adicionalmente, ocorre menor peroxidação plasmática de lipídios e, consequentemente, menos dano oxidativo em frangos de corte, em resposta ao uso dos OLES.

Essential oils are an alternative to growth promoters based on antibiotics used in animal diets, due to its antimicrobial potential, and immunomodulatory properties. Serum proteins electrophoresis and plasma lipid peroxidation were evaluated in broilers fed with diets supplemented with antibiotics or essential oils from oregano (Origanum vulgare L.), sage (Salvia officinalis L.), rosemary (Rosmarinus officinalis L.) and pepper (Capsicum frutescens L.) crude extract (OLES). The animals (n=910) were distributed within five treatment groups and seven replicates containing 26 birds each one: control group (diet without additives); the group receiving an antibiotic growth promoter diet (Tatb); and the groups T50, T100 and T150 (supplemented with 50, 100 and 150mg kg-1 of OLES, respectively). After 42 days, seven animals were randomly selected for serum proteins electrophoretic fractionation and plasma lipid peroxidation evaluation by thiobarbituric acid reactive species (TBARS) test. Total globulins (T150), betaglobulin fraction (Tatb and T150) and plasma TBARS levels in the groups that received OLES (P<0.05) presented a decrease in relation to the control group. These results suggests lower stimulus to the humoral immune response at the higher dose of OLES, as occurred in the antibiotic growth promoter group. Moreover, it suggests lower lipid peroxidation and, consequently, lower oxidative damage caused by OLES use in broiler chickens.

Trypanosoma evansi: cholinesterase activity in acutely infected Wistar rats.

The aim of this study was to evaluate cholinesterase activity during the early acute phase of Trypanosoma evansi infection in rats. Fifteen male Wistar rats were randomly distributed into three groups (n=5 animals per group): two trypanosome-infected groups (T3 and T5) and uninfected controls (C). The animals were inoculated intraperitoneally with 10(6) trypanosomes. The blood was collected by cardiac puncture on the 3rd (T3) or 5th day post-infection (T5 and C). Cerebrum and cerebellum were removed for the evaluation of acetylcholinesterase (AChE) activity. AChE activity was also evaluated in whole blood and butyrylcholinesterase activity (BUChE) in plasma samples. Parasitemia were progressive increase and parasites were observed in the peripheral blood of all infected animals one day post-inoculation. AChE activity was not altered in cerebrum and cerebellum tissues. AChE activity in blood significantly decreased in the T3 and T5 groups (26.63 and 25.86mU/lmolHb) compared with the control (37.84mU/lmolHb). In addition BUChE activity in plasma was lower in the T3 (7.01micromol BTC hydrolyzed/h/mL) than the T5 and C groups (9.84 and 12.00micromol BTC hydrolyzed/h/mL). This study therefore, shows that reductions in the activity of cholinesterase occur in acute infection by T. evansi in rats and this demonstrates an important change occurring in animals infected by the protozoan and may indicate a potential role the enzymes play in the mechanism of disease.

Lipid peroxidation associated with anemia in rats experimentally infected with Trypanosoma evansi.

This study aimed to assess the plasma lipid peroxidation and the susceptibility of erythrocytes to in vitro peroxidation as indicators of oxidative damage in erythrocytes and their roles in the pathogenesis of anemia during the early acute phase of Trypanosoma evansi infection in rats. Fifty male Wistar rats were randomly distributed into seven groups: three trypanosome-infected groups (T(2), T(4) and T(6); n=10 animals per group) and four uninfected controls (C(0), C(2), C(4) and C(6); n=5 animals per group). Animals from trypanosome-infected groups were inoculated intraperitoneally with 10(6) trypanosomes. Blood samples were collected by cardiac puncture before infection (day 0; group C(0)) or on the 2nd (C(2) and T(2)), 4th (C(4) and T(4)) and 6th (C(6) and T(6)) day post-infection (dpi). Samples were analyzed for red blood cell (RBC) count, hemoglobin (Hb) concentration, packed cell volume (PCV), plasma malondialdehyde (MDA) and in vitro peroxidation of erythrocytes. The mean values of the hematological indices gradually decreased in the infected rats compared with the control. MDA was significantly increased (P<0.001) on the 6th dpi in infected versus control animals and was negatively correlated with PCV (P<0.001; R(2)=0.372). The values for erythrocyte in vitro peroxidation were higher for groups T(4) and T(6) than for the control rats (P<0.01). A positive correlation between erythrocyte peroxidation and MDA (P<0.001; R(2)=0.414) was observed. The results of this study indicate that T. evansi infection in rats is associated with oxidative stress, indicated by lipid peroxidation and oxidative damage in erythrocyte membranes, as demonstrated by in vitro peroxidation. This may be one of the causes of anemia in acute trypanosomosis.

Resposta eritropoética de ratos em diferentes graus de parasitemia por Trypanosoma evansi / Erithropoietic response in Trypanosoma evansi infected rats with different parasitaemia intensity

O Trypanosoma evansi é um protozoário hemoflagelado que causa, em várias espécies, uma doença caracterizada por altos níveis de parasitemia, com rápido desenvolvimento de anemia. Este trabalho teve como objetivo investigar a relação entre o grau de parasitemia e a alteração na eritropoese de ratos (Rattus norvegicus) da linhagem Wistar infectados experimentalmente com T. evansi. Foram utilizados 42 ratos, dos quais 36 foram inoculados pela via intraperitoneal com 0,2ml de sangue, contendo 2,5 x 104 parasitas. Seis ratos não-inoculados foram utilizados como controles. Após inoculação, a parasitemia foi avaliada a cada 12h. Os grupos para análise foram estipulados de acordo com a média de tripanossomas em 10 campos homogêneos focados aleatoriamente, sendo: A, controle; B, animais que apresentaram um grau de parasitemia entre 1-10 tripanossomas/campo; C, ratos com 11-20 tripanossomas/campo; D, ratos com 21-30 tripanossomas/campo; E, ratos com 31-40 tripanossomas/campo; F, 41-50 tripanossomas/campo; e G, ratos com mais de 51 tripanossomas/campo. Quando os animais apresentaram o número de protozoários equivalente ao grupo, foram coletadas amostras de sangue para realização de hemograma e dosagem de ferro, e foi realizada citologia de medula óssea para avaliação da relação mielóide:eritróide. A análise estatística mostrou redução significativa das hemácias e do hematócrito a partir de 31 tripanossomas/campo (grupos E, F e G; P<0,005) e a redução de hemoglobina ocorreu a partir de 41 tripanossomas/campo (grupos F e G; P<0,005). A relação mielóide:eritróide foi reduzida de 0,7 para 0,6 a partir de 41 tripanossomas/campo (grupos F e G; P<0,005). Não foram detectadas variações na concentração de ferro. Os dados obtidos demonstraram que ratos com parasitemia acima de 31 tripanossomas por campo desenvolvem uma anemia aguda, com um aumento compensatório na atividade hematopoética.

Trypanosoma evansi is a flagellate protozoan that causes a disease characterized by high parasitemia and acute anemia in various species. This study was aimed at evaluating and establishing a relationship between different parasitemia levels and eritropoyesis in Wistar rats (Rattus norvegicus) experimentally infected by T. evansi. Forty two animals were used. In 36 animals parasites were inoculated by intraperitoneal blood injection of 0.2ml containing 2.5x104 parasites. Six non-inoculated animals were used as controls. Parasitemia was evaluated every 12 hours and the animals were allocated in groups according to parasitemia levels. Then they were classified according to average number of parasites in 10 random homogeneous fields, Group A: control (not-inoculated); B: rats with 1-10 trypanosomes/field; C: 11-20 trypanosomes/field; D: 21-30 trypanosomes/field; E: 31-40 trypanosomes/field; F: 41-50 trypanosomes/field; G: more then 51. Blood samples were taken when the animals reached the correspondent group number of parasites. Hemogram and iron levels were evaluated and a bone marrow cytology was performed to detect the myeloid:erythroid ratio. Statistical analysis showed a significant reduction on red blood cells count and hematocrit from group E on and also hemoglobin on groups F and G. The myeloid:erythroid ratio reduced from 0.7 to 0.6 on groups F and G (P<0.005). Iron levels alterations were not detected. These data showed that Wistar rats with parasitemia higher then 31 parasites per field have an acute anemia associated to a compensatory hematopoietic activity.