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1.
Rev. bras. parasitol. vet ; 30(1): e017020, 2021. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1156227

RESUMO

Abstract Autophagy plays an important role in maintaining cell homeostasis through degradation of denatured proteins and other biological macromolecules. In recent years, many researchers focus on mechanism of autophagy in apicomplexan parasites, but little was known about this process in avian coccidia. In our present study. The cloning, sequencing and characterization of autophagy-related gene (Etatg8) were investigated by quantitative real-time PCR (RT-qPCR), western blotting (WB), indirect immunofluorescence assays (IFAs) and transmission electron microscopy (TEM), respectively. The results have shown 375-bp ORF of Etatg8, encoding a protein of 124 amino acids in E. tenella, the protein structure and properties are similar to other apicomplexan parasites. RT-qPCR revealed Etatg8 gene expression during four developmental stages in E. tenella, but their transcriptional levels were significantly higher at the unsporulated oocysts stage. WB and IFA showed that EtATG8 was lipidated to bind the autophagosome membrane under starvation or rapamycin conditions, and aggregated in the cytoplasm of sporozoites and merozoites, however, the process of autophagosome membrane production can be inhibited by 3-methyladenine. In conclusion, we found that E. tenella has a conserved autophagy mechanism like other apicomplexan parasites, and EtATG8 can be used as a marker for future research on autophagy targeting avian coccidia.


Resumo A autofagia desempenha um papel importante na manutenção da homeostase celular através da degradação de proteínas desnaturadas e outras macromoléculas biológicas. Nos últimos anos, muitos pesquisadores se concentraram no mecanismo da autofagia em parasitas apicomplexos, mas pouco se sabe sobre esse processo na coccidia aviária. No presente estudo, a clonagem, sequenciamento e caracterização de gene relacionado à autofagia Etatg8 foram investigados pela PCR quantitativa em tempo real (RT-qPCR), mancha ocidental (WB), ensaios indiretos de imunofluorescência (IFAs) e microscopia eletrônica de transmissão (TEM), respectivamente. Os resultados mostraram que o gene Etatg8 de E. tenella possui uma ORF de 375 bp, codificando uma proteína de 124 aminoácidos com estrutura e propriedades semelhantes à de outros apicomplexos. RT-qPCR revelou que Etatg8 é expresso durante os quatro estágios de desenvolvimento de E. tenella. Entretanto, seus níveis transcricionais foram significativamente mais elevados na fase de oocisto não esporulados. Os ensaios de manchas ocidental (WB) e de imunofluorescência (IFA) mostraram que a proteína EtATG8 foi lipidada para ligar-se à membrana do autofagossomo sob condições de deficiência nutritiva (em presença de rapamicina) e se agregar no citoplasma de esporozoítas e merozoítas. No entanto, o processo de produção de membrana do autofagossomo pode ser inibido por um inibidor de autofagia (3-meetiladeninatiladenina, 3-MA). Em conclusão, foi demonstrado que E. tenella tem um mecanismo de autofagia conservado, semelhante ao de outros parasitas apicomplexos, e que EtATG8 pode ser usado como um marcador para futuras pesquisas sobre autofagia direcionada à coccidiose aviária.


Assuntos
Animais , Autofagia/fisiologia , Doenças das Aves/parasitologia , Galinhas/parasitologia , Eimeria tenella/fisiologia , Coccidiose/veterinária , Família da Proteína 8 Relacionada à Autofagia/química , Autofagia/genética , Doenças das Aves/prevenção & controle , Marcadores Genéticos/fisiologia , China , Reação em Cadeia da Polimerase , Eimeria tenella/genética , Clonagem Molecular/métodos , Coccidiose/prevenção & controle , Oocistos/isolamento & purificação , Oocistos/fisiologia , Esporozoítos/isolamento & purificação , Esporozoítos/fisiologia , Microscopia Eletrônica de Transmissão , Merozoítos/isolamento & purificação , Merozoítos/fisiologia , Família da Proteína 8 Relacionada à Autofagia/genética
3.
Sci Rep ; 10(1): 18152, 2020 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-33097768

RESUMO

Environmental challenges are integrated in the inmunoneuroendocrine interplay, impacting the immune system of the challenged individuals, and potentially implying transgenerational effects on their offspring. This study addressed whether dietary supplementation with thymol can modulate the immune response of adult Japanese quail when simultaneously exposed to an inoculum of inactivated Salmonella Enteritidis and a chronic heat stress (CHS). We also evaluated whether the experienced situations by adults can affect the immune response of their undisturbed offspring. In the parental generation, supplemented quail exposed to CHS had a higher inflammatory response and similar values of the heterophil/lymphocyte (H/L) ratio than those that were not supplemented. In their offspring, those chicks whose parents were exposed to CHS showed higher inflammatory response and lower antibody production. Regarding the H/L ratio, chicks whose parents were supplemented showed lower H/L ratio values. Dietary supplementation with thymol partially and positively modulated the inflammatory response and avoided H/L ratio alteration in the parental generation exposed to high environmental temperatures, suggesting these adults were better at dealing with the challenge. The lower H/L ratio values in the offspring suggests that chicks are more capable to deal with potential stressful situations associated with conventional breeding conditions.


Assuntos
Ração Animal , Doenças das Aves/prevenção & controle , Coturnix/imunologia , Transtornos de Estresse por Calor/veterinária , Salmonella enteritidis/imunologia , Timol/administração & dosagem , Animais , Doenças das Aves/sangue , Doenças das Aves/imunologia , Doenças das Aves/microbiologia , Coturnix/microbiologia , Feminino , Transtornos de Estresse por Calor/sangue , Transtornos de Estresse por Calor/imunologia , Transtornos de Estresse por Calor/prevenção & controle , Temperatura Alta/efeitos adversos , Contagem de Linfócitos , Linfócitos/imunologia , Masculino , Exposição Materna , Neuroimunomodulação/efeitos dos fármacos , Óvulo/imunologia , Exposição Paterna , Fatores Sexuais
4.
Vet Parasitol ; 280: 109065, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32203695

RESUMO

Lice are ectoparasites capable of affecting birds, and can result in direct and indirect damage to their host. Afoxolaner is an isoxazoline that has been shown to be effective against these ectoparasites without known adverse effects. The objective of this research was to evaluate the effect of afoxolaner on lice in pheasants and plain chachalacas. A total of 29 pheasants of different genera and species (Chrysolophus pictus, C. amherstiae, Lophura swinghoii, L. nycthemera, Phasianus colchicus, and Syrmaticus reevesii) and 18 West Mexican Chachalacas (Ortalis poliocephala) naturally infested with Goniodes pavonis were used. The birds were allocated to one of two groups: group 1 treated with 2.50 mg/kg of afoxolaner, and group 2 given no treatment. Ectoparasites were collected using the adhesive tape technique and identified. Afoxolaner was administered later as a single dose to group 1, and the clinical assessment to detect ectoparasites was repeated 28 days post-treatment. On day 28 post-treatment, group 1 was found to be negative for the presence of lice. The body weights were compared at the beginning and end of the clinical assessment in both groups and a significant difference in weight of treated birds was found. The mean body weight decreased by 0.017 g in control group, whereas it increased by 0.016 g in treated group. Oral administration of afoxolaner is an effective option for the treatment of Goniodes pavonis infestations in zoo birds.


Assuntos
Doenças das Aves/prevenção & controle , Galliformes , Controle de Insetos , Inseticidas , Iscnóceros , Isoxazóis , Infestações por Piolhos/veterinária , Naftalenos , Animais , Doenças das Aves/parasitologia , Infestações por Piolhos/parasitologia , Infestações por Piolhos/prevenção & controle
5.
Epidemiol Infect ; 145(11): 2263-2268, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28554339

RESUMO

Zoonotic diseases are a significant health threat for humans and animals. To better understand the epidemiology, etiology, and pathology of infectious agents affecting humans and animals combined approaches are needed. Here we describe an epidemiological investigation conducted by physicians and veterinarians after a reported case of psittacosis. Upon admission suffering from respiratory distress syndrome in a hospital and with a history of bird contact, a female patient was serologically diagnosed with psittacosis. After the case notification, veterinarians were able to investigate the source of infection by detecting Chlamydia psittaci in her pet cockatiel. The bird was hospitalized and successfully treated. In addition, the establishment where the pet bird was purchased was traced and through molecular techniques other birds intended to be sold as pets tested positive for C. psittaci. As a result, sanitary measures were applied and the establishment then was closed down. The birds intended for the pet commerce were treated and retested with negative molecular results for C. psittaci, thus avoiding disease propagation. Reliable data about zoonotic diseases can only be generated through the application of multidisciplinary approaches which take into account the epidemiological factors and interactions of humans, animals and their environments as an integrated system.


Assuntos
Doenças das Aves/prevenção & controle , Chlamydophila psittaci/isolamento & purificação , Papagaios , Psitacose/prevenção & controle , Zoonoses/prevenção & controle , Animais , Doenças das Aves/diagnóstico , Doenças das Aves/microbiologia , Brasil , Comércio , Feminino , Humanos , Psitacose/diagnóstico , Psitacose/microbiologia , Adulto Jovem , Zoonoses/diagnóstico , Zoonoses/microbiologia
6.
Ci. Rural ; 46(8): 1438-1442, ago. 2016. graf
Artigo em Inglês | VETINDEX | ID: vti-22532

RESUMO

The efficacy of 28 individual or blended disinfectants against avian Salmonella enterica serovar Enteritidis and Escherichia coli strains was determined. An in vitro test in the presence and absence of serum as source of organic material was conducted. Povidone-iodine (releasing 1% available iodine), 1% potassium permanganate, 70% ethanol, 2% chlorhexidine digluconate and three commercial formulations based on quaternary ammonium compounds + formaldehyde or cresol derivates were the most effective against all strains tested and reduced bacterial counts by more than 106 times (6-log10) regardless of the presence of organic matter. These commercial compounds as well as ethanol and chlorhexidine among the individual substances tested might be helpful in the adoption of environmental control measures against these two enterobacteria in poultry industry.(AU)


A eficácia de 28 desinfetantes individuais ou combinados sobre cepas de Salmonella enterica serovar Enteritidis e Escherichia coli foi determinada. Um teste in vitro em presença e ausência de soro como fonte de matéria orgânica foi realizado. Iodopovidona (contendo 1% de iodo ativo), permanganato de potássio a 1%, etanol a 70%, digliconato de clorexidina e três formulações comerciais, baseadas em compostos de amônia quaternária + formaldeído ou em derivados de cresóis, foram mais eficazes contra as cepas bacterianas testadas, reduzindo em mais 106 vezes (6-log) a contagem bacteriana, independente da presença de matéria orgânica. Esses compostos comerciais, bem como o etanol e a clorexidina entre as substâncias químicas individuais avaliadas, podem ser úteis para a implementação de medidas de controle ambiental contra estas duas enterobacterias de importância para a indústria aviária.(AU)


Assuntos
Animais , Salmonella enterica/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Desinfetantes/administração & dosagem , Doenças das Aves/prevenção & controle , Espanha , Técnicas In Vitro/métodos
7.
Br J Nutr ; 113(4): 549-59, 2015 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-25614252

RESUMO

The aim of the present study was to evaluate the effects of heat stress (HS) and methionine supplementation on the markers of stress and on the gene expression levels of uncoupling proteins (UCP), betaine-homocysteine methyltransferase (BHMT), cystathionine ß-synthase (CBS), glutathione synthetase (GSS) and glutathione peroxidase 7 (GPx7). Broilers from 1 to 21 d and from 22 to 42 d of age were divided into three treatment groups related to methionine supplementation: without methionine supplementation (MD); recommended level of methionine supplementation (DL1); excess methionine supplementation (DL2). The broilers were either kept at a comfortable thermal temperature or exposed to HS (38°C for 24 h). During the starter period, we observed the effects of the interaction between diet and environment on the gene expression levels of UCP, BHMT and GSS. Higher gene expression levels of UCP and BHMT were observed in broilers that were maintained at thermal comfort conditions and received the MD diet. HS broilers fed the DL1 and DL2 diets had the highest expression level of GSS. The expression levels of the CBS and GPx7 genes were influenced by both the environment and methionine supplementation. During the grower period, the gene expression levels of BHMT, CBS, GSS and GPx7 were affected by the diet × environment interaction. A higher expression level of BHMT was observed in broilers maintained at thermal comfort conditions and on the MD diet. HS induced higher expression levels of CBS, GSS and GPx7 in broilers that received the DL1 and DL2 diets. The present results suggest that under HS conditions, methionine supplementation could mitigate the effects of stress, since methionine contributed to the increased expression levels of genes related to antioxidant activity.


Assuntos
Doenças das Aves/prevenção & controle , Dieta/veterinária , Regulação da Expressão Gênica no Desenvolvimento , Transtornos de Estresse por Calor/veterinária , Metionina/uso terapêutico , Estresse Oxidativo , Músculos Peitorais/enzimologia , Animais , Animais Endogâmicos , Antioxidantes/administração & dosagem , Antioxidantes/uso terapêutico , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Betaína-Homocisteína S-Metiltransferase/genética , Betaína-Homocisteína S-Metiltransferase/metabolismo , Biomarcadores/sangue , Biomarcadores/metabolismo , Doenças das Aves/dietoterapia , Doenças das Aves/metabolismo , Doenças das Aves/patologia , Galinhas , Ingestão de Energia , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Glutationa Sintase/genética , Glutationa Sintase/metabolismo , Transtornos de Estresse por Calor/dietoterapia , Transtornos de Estresse por Calor/metabolismo , Transtornos de Estresse por Calor/prevenção & controle , Homocisteína/sangue , Canais Iônicos/genética , Canais Iônicos/metabolismo , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Metionina/administração & dosagem , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Músculos Peitorais/metabolismo , Músculos Peitorais/patologia , Proteína Desacopladora 1 , Aumento de Peso
8.
R. bras. Ci. avíc. ; 17(3): 399-404, jul.-set. 2015. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: vti-17085

RESUMO

Avian encephalomyelitis is caused by an Hepatovirus and primarily affects chickens. Chickens of all ages are susceptible to the virus, but the nervous symptoms are manifested only in young chicks, between one to five weeks of age. During the last thirty years, avian encephalomyelitis appeared to be well controlled by breeder vaccination. However, the increase of the number of cases is causing concern in the poultry industry. In the present study, we performed a retrospective analysis of the cases presenting histological lesions compatible with avian encephalomyelitis in broilers. The evaluated cases affected broilers from one to 35 days old from the southern region of Brazil. Only cases with compatible microscopic lesions and associated with clinical symptoms in the field were considered. In addition the histopathological diagnosis, sera were tested by ELISA (Enzyme-Linked Immunosorbent Assay). Considering the clinical, histopathological, and serological evidences, the disease was confirmed, showing an increase in outbreaks from the last quarter of 2012, extending through 2013. The cause of this increase is not clear, although we suspect vaccine or vaccination error. Enhancing vaccinated breeders flocks monitoring before the beginning of egg production and/or using a protocol with two vaccinations is recommended.(AU)


Assuntos
Animais , Doenças das Aves/classificação , Doenças das Aves/diagnóstico , Doenças das Aves/prevenção & controle , Encefalomielite/classificação , Encefalomielite/veterinária
9.
Rev. bras. ciênc. avic ; 17(3): 399-404, jul.-set. 2015. ilus, tab, graf
Artigo em Inglês | VETINDEX | ID: biblio-1490162

RESUMO

Avian encephalomyelitis is caused by an Hepatovirus and primarily affects chickens. Chickens of all ages are susceptible to the virus, but the nervous symptoms are manifested only in young chicks, between one to five weeks of age. During the last thirty years, avian encephalomyelitis appeared to be well controlled by breeder vaccination. However, the increase of the number of cases is causing concern in the poultry industry. In the present study, we performed a retrospective analysis of the cases presenting histological lesions compatible with avian encephalomyelitis in broilers. The evaluated cases affected broilers from one to 35 days old from the southern region of Brazil. Only cases with compatible microscopic lesions and associated with clinical symptoms in the field were considered. In addition the histopathological diagnosis, sera were tested by ELISA (Enzyme-Linked Immunosorbent Assay). Considering the clinical, histopathological, and serological evidences, the disease was confirmed, showing an increase in outbreaks from the last quarter of 2012, extending through 2013. The cause of this increase is not clear, although we suspect vaccine or vaccination error. Enhancing vaccinated breeders flocks monitoring before the beginning of egg production and/or using a protocol with two vaccinations is recommended.


Assuntos
Animais , Doenças das Aves/classificação , Doenças das Aves/diagnóstico , Doenças das Aves/prevenção & controle , Encefalomielite/classificação , Encefalomielite/veterinária
10.
Rev Sci Tech ; 32(3): 789-800, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24761731

RESUMO

The aim of this study was to evaluate the efficiency of the use of wire nets of various mesh sizes to enhance biosecurity in the poultry industry in Brazil by preventing other bird species from entering chicken houses. The Brazilian poultry industry is technologically advanced and employs updated technology. The current Brazilian guidelines recommend the use of 25.40 mm mesh. However, scientific evidence of the efficiency of the nets recommended by these guidelines is lacking. In this study, a bird biometric methodology was developed to evaluate bird species. The methodology was based on the body dimensions of the animal, and it employed a new statistical design to analyse the data. Three groups of bird species were designated according to their importance. The value of this criterion (the importance of the species) was estimated by assessing the ability of birds to pass through the net. The paradigm was used to study 23 wild avian species that are naturally present in Brazil. The best results were observed for nets with a mesh size < or = 19.11 mm. This mesh size was able to efficiently restrain all of the species studied. However, in the same test, the net with 25.40 mm mesh could not restrain 11 bird species, one of which was Passer domesticus, which is found worldwide. On the basis of these results, the use of 19.11 mm mesh should be strongly recommended in order to achieve biosecurity of poultry houses.


Assuntos
Criação de Animais Domésticos , Doenças das Aves/prevenção & controle , Abrigo para Animais , Criação de Animais Domésticos/métodos , Criação de Animais Domésticos/normas , Animais , Animais Selvagens/anatomia & histologia , Biometria/métodos , Doenças das Aves/epidemiologia , Doenças das Aves/transmissão , Aves/anatomia & histologia , Brasil/epidemiologia , Feminino , Abrigo para Animais/normas , Masculino , Aves Domésticas , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/transmissão
11.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);64(6): 1569-1576, Dec. 2012. tab
Artigo em Inglês | LILACS | ID: lil-660226

RESUMO

Adhesion proteins from Mycoplasma gallisepticum (MG) encoded by cytadhesion genes mgc1 and mgc2 were cloned into plasmid vectors and transformed into E. coli. Seventeen groups of specific-pathogen free (SPF), birds at four weeks of age were used to inoculate these two proteins (MGC1 and MGC2) mixed into an oil emulsion creating a novel MG vaccine. Six different protein concentrations (50, 100, 200, 400, 800, and 1000µg/bird) were tested with two equal concentration doses at four and seven weeks of age. In addition, many control groups were needed such as bacterin, membrane, no vaccine or challenge, oil emulsion alone, and no vaccine but challenged. Three weeks following the second vaccination, 50% of the birds in each treatment group were challenged with MG strain S6. The remaining birds were left as contacts to verify protection against horizontal transmission. All birds were bled before vaccinations, challenge and euthanasia. Birds were negative for MG at the first vaccination, as shown by serum plate agglutination test. At necropsy, tissue samples (trachea, lungs, and air sacs) were collected for histopathological examination. Swabs from trachea were used for PCR analysis. ELISA results showed a strong immune response to both protein preparations and almost the same response level for different doses tested, proving the immunogenic features of MGC1 and MGC2. However, humoral responses failed to prevent MG infection and disease when challenged as demonstrated by PCR and histopathology. MGC1 contact birds showed some degree of infection by PCR analysis. In addition, histopathological and ELISA results suggest that contact birds did not have enough time to develop lesions and to mount an immune response.


Os genes mgc1 e mgc2, codificadores de duas proteínas de adesão (MGC1 e MGC2) da bactéria Mycoplasma gallisepticum, foram clonados em E. coli. Dezessete grupos de aves livres de patógenos específicos (SPF), com quatro semanas de idade, foram inoculados com uma emulsão oleosa contendo as proteínas MGC1 e MGC2 purificadas. Seis concentrações (50, 100, 200, 400, 800, e 1000µg/ave) foram testadas com duas doses idênticas, às quatro e sete semanas de vida, respectivamente. Além disso, grupos controles foram avaliados com uma vacina comercial contra micoplasmose aviária, membrana de MG, grupo sem vacina/sem desafio, grupo vacina oleosa de MGC1 sem desafio, grupo com vacina oleosa de MGC2 sem desafio, grupo desafiado mas sem vacina. Três semanas após a segunda e a última vacinação, 50% dos animais dos grupos tratamentos foram desafiados com a cepa S6 de MG. O restante dos animais foi deixado como contato para averiguar proteção contra a transmissão horizontal da doença. Amostras de sangue de todas as aves foram coletadas antes das vacinações, do desafio e da eutanásia. As aves eram negativas para MG às quatro semanas de vida, conforme visto na aglutinação em placa. Na necropsia, tecidos (traqueia, pulmão e sacos aéreos) foram coletados para exame histopatológico. Suabes da traqueia foram utilizados para a PCR. Os resultados do ELISA demonstraram forte resposta imune contra as duas proteínas testadas e resposta similar independentemente do número de doses, provando a sua capacidade imunogênica. Porém, esta resposta humoral gerada foi incapaz de prevenir a infecção e a doença após desafio, conforme demonstrado pelos exames PCR e histopatológico. Aves-contato, inoculadas com MGC1, demonstraram estar infectadas nas análises de PCR. Além disso, os resultados do histopatológico e ELISA sugerem que os animais-contato não tiveram tempo suficiente para demonstrar lesões ou resposta imune.


Assuntos
Animais , Mycoplasma gallisepticum/imunologia , Noxas/análise , Testes Imunológicos/veterinária , Vacinas/administração & dosagem , Aves Domésticas/análise , Doenças das Aves/prevenção & controle , Proteínas/análise
12.
Arq. bras. med. vet. zootec ; 64(6): 1569-1576, 2012. tab
Artigo em Inglês | VETINDEX | ID: vti-10896

RESUMO

Adhesion proteins from Mycoplasma gallisepticum (MG) encoded by cytadhesion genes mgc1 and mgc2 were cloned into plasmid vectors and transformed into E. coli. Seventeen groups of specific-pathogen free (SPF), birds at four weeks of age were used to inoculate these two proteins (MGC1 and MGC2) mixed into an oil emulsion creating a novel MG vaccine. Six different protein concentrations (50, 100, 200, 400, 800, and 1000µg/bird) were tested with two equal concentration doses at four and seven weeks of age. In addition, many control groups were needed such as bacterin, membrane, no vaccine or challenge, oil emulsion alone, and no vaccine but challenged. Three weeks following the second vaccination, 50% of the birds in each treatment group were challenged with MG strain S6. The remaining birds were left as contacts to verify protection against horizontal transmission. All birds were bled before vaccinations, challenge and euthanasia. Birds were negative for MG at the first vaccination, as shown by serum plate agglutination test. At necropsy, tissue samples (trachea, lungs, and air sacs) were collected for histopathological examination. Swabs from trachea were used for PCR analysis. ELISA results showed a strong immune response to both protein preparations and almost the same response level for different doses tested, proving the immunogenic features of MGC1 and MGC2. However, humoral responses failed to prevent MG infection and disease when challenged as demonstrated by PCR and histopathology. MGC1 contact birds showed some degree of infection by PCR analysis. In addition, histopathological and ELISA results suggest that contact birds did not have enough time to develop lesions and to mount an immune response.(AU)


Os genes mgc1 e mgc2, codificadores de duas proteínas de adesão (MGC1 e MGC2) da bactéria Mycoplasma gallisepticum, foram clonados em E. coli. Dezessete grupos de aves livres de patógenos específicos (SPF), com quatro semanas de idade, foram inoculados com uma emulsão oleosa contendo as proteínas MGC1 e MGC2 purificadas. Seis concentrações (50, 100, 200, 400, 800, e 1000µg/ave) foram testadas com duas doses idênticas, às quatro e sete semanas de vida, respectivamente. Além disso, grupos controles foram avaliados com uma vacina comercial contra micoplasmose aviária, membrana de MG, grupo sem vacina/sem desafio, grupo vacina oleosa de MGC1 sem desafio, grupo com vacina oleosa de MGC2 sem desafio, grupo desafiado mas sem vacina. Três semanas após a segunda e a última vacinação, 50% dos animais dos grupos tratamentos foram desafiados com a cepa S6 de MG. O restante dos animais foi deixado como contato para averiguar proteção contra a transmissão horizontal da doença. Amostras de sangue de todas as aves foram coletadas antes das vacinações, do desafio e da eutanásia. As aves eram negativas para MG às quatro semanas de vida, conforme visto na aglutinação em placa. Na necropsia, tecidos (traqueia, pulmão e sacos aéreos) foram coletados para exame histopatológico. Suabes da traqueia foram utilizados para a PCR. Os resultados do ELISA demonstraram forte resposta imune contra as duas proteínas testadas e resposta similar independentemente do número de doses, provando a sua capacidade imunogênica. Porém, esta resposta humoral gerada foi incapaz de prevenir a infecção e a doença após desafio, conforme demonstrado pelos exames PCR e histopatológico. Aves-contato, inoculadas com MGC1, demonstraram estar infectadas nas análises de PCR. Além disso, os resultados do histopatológico e ELISA sugerem que os animais-contato não tiveram tempo suficiente para demonstrar lesões ou resposta imune.(AU)


Assuntos
Animais , Vacinas/administração & dosagem , Mycoplasma gallisepticum/imunologia , Noxas/análise , Testes Imunológicos/veterinária , Proteínas/análise , Aves Domésticas/análise , Doenças das Aves/prevenção & controle
14.
Trop Anim Health Prod ; 41(7): 1325-33, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19253000

RESUMO

The purposes of this study were to model a vaccination regimen for Newcastle disease virus (NDV) in pigeons, and to evaluate the susceptibility and behavior of vaccinated birds against a highly pathogenic NDV Brazilian strain. Antibody response was assessed by means of hemagglutination inhibition test (HI), and viral genome excretion by means of RT-PCR. Vaccinal strains (La Sota and Ulster) induced high antibody titers without any adverse effects, both in inoculated and in sentinel birds. A viral strain pathogenic for chickens did not produce clinical signs of the disease in experimentally infected pigeons. Only 4 out of 10 vaccinated pigeons shed NDV genome, and just for two days. Results confirmed the high infectivity of the vaccinal strains used, as all nonvaccinated pigeons showed antibody titers as high as those of vaccinated birds.


Assuntos
Doenças das Aves/prevenção & controle , Doenças das Aves/virologia , Columbidae , Imunoterapia Ativa/veterinária , Vírus da Doença de Newcastle/imunologia , Vacinas Virais/uso terapêutico , Animais , Primers do DNA/genética , Testes de Inibição da Hemaglutinação/veterinária , Imunoterapia Ativa/métodos , Eliminação de Partículas Virais/genética
16.
Mycopathologia ; 166(2): 61-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18459065

RESUMO

Cryptococcus neoformans is an opportunistic basidiomycete yeast that causes life-threatening infections as meningoencephalitis primarily in immunocompromised hosts, generally associated with AIDS. The source of this organism is mainly pigeon excreta; however, other avian species' excreta are implicated as a source of this yeast. The occurrence of C. neoformans and Cryptococcus gattii in bird excreta in the state of Paraná in Brazil was determined in this study. A total of 141 samples of Passerine and Psittacine excreta from captive birds were collected. Additionally, 25 clinical samples from Hospital de Clínicas, in the state of Paraná were also analyzed. The determination of molecular and mating type of the isolates was performed by PCR fingerprinting, multiplex PCR, and mating type PCR. Cryptococcus neoformans var. grubii (VNI) was isolated from 36 (25.53%) of Passerine and Psittacine excreta samples. Almost all clinical samples, except one (C. gattii VGI), were classified as C. neoformans var. grubii (VNI). All environmental and clinical isolates were mating type alpha. These findings reinforce that, besides pigeon excreta, the excreta of these birds can also be a reservoir of C. neoformans in domestic and public environments and is of zoonotic importance to immunocompromised patients.


Assuntos
Doenças das Aves/microbiologia , Aves/microbiologia , Criptococose/veterinária , Cryptococcus neoformans/classificação , Cryptococcus neoformans/isolamento & purificação , Adulto , Animais , Doenças das Aves/prevenção & controle , Brasil/epidemiologia , Criptococose/microbiologia , Criptococose/prevenção & controle , Cryptococcus neoformans/genética , Impressões Digitais de DNA , DNA Fúngico/genética , Reservatórios de Doenças/microbiologia , Fezes/microbiologia , Feminino , Proteínas Fúngicas/genética , Humanos , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Reação em Cadeia da Polimerase
17.
J Zoo Wildl Med ; 38(2): 337-40, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17679521

RESUMO

Passive transfer of maternal antibodies against West Nile virus (WNV) was studied in a captive population of Chilean (Phoenicopterus chilensis) and Caribbean flamingos (Phoenicopterus ruber ruber). Transfer of WNV antibodies from hens to chicks was documented and measured by plaque-reduction neutralization test. Hen titers were significantly correlated to chick titers. Mean half-life of maternal WNV antibodies was 13.4 days in chicks for which half-life was measurable.


Assuntos
Anticorpos Antivirais/sangue , Doenças das Aves/imunologia , Imunidade Materno-Adquirida , Febre do Nilo Ocidental/veterinária , Vírus do Nilo Ocidental/imunologia , Animais , Animais Selvagens , Doenças das Aves/prevenção & controle , Doenças das Aves/transmissão , Aves , Feminino , Masculino , Testes de Neutralização/veterinária , Febre do Nilo Ocidental/imunologia , Febre do Nilo Ocidental/prevenção & controle , Febre do Nilo Ocidental/transmissão
18.
BMC Biotechnol ; 6: 2, 2006 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-16396687

RESUMO

BACKGROUND: The use of lactic acid bacteria as vehicles to delivery antigens to immunize animals is a promising issue. When genetically modified, these bacteria can induce a specific local and systemic immune response against selected pathogens. Gastric acid and bile salts tolerance, production of antagonistic substances against pathogenic microorganisms, and adhesive ability to gut epithelium are other important characteristics that make these bacteria useful for oral immunization. RESULTS: Bacteria isolated on de Man, Rogosa and Sharpe medium (MRS) from different gastrointestinal portions of broiler chicks were evaluated for their resistance to artificial gastric acid and bile salts, production of hydrogen peroxide, and cell surface hydrophobicity. Thirty-eight isolates were first typed at species level by PCR amplification of 16S-23S rRNA intergenic spacers using universal primers that anneal within 16S and 23S genes, followed by restriction digestion analyses of PCR amplicons (PCR-ARDRA). An expression cassette was assembled onto the pCR2.1-Topo vector by cloning the promoter, leader peptide, cell wall anchor and terminator sequences derived from the laminin binding S-layer protein gene of L. crispatus strain F5.7 (lbs gene). A sequence encoding the green fluorescent protein (GFP) was inserted as reporter gene, and an erythromycin resistance gene was added as selective marker. All constructs were able to express GFP in the cloning host E. coli XL1-Blue and different Lactobacillus strains as verified by FACS and laser scanning confocal microscopy. CONCLUSION: Lactobacillus isolated from gastrointestinal tract of broiler chickens and selected for probiotic characteristics can be genetically modified by introducing an expression cassette into the lbs locus. The transformed bacteria expressed on its cell wall surface different fluorescent proteins used as reporters of promoter function. It is possible then that similar bacterial model expressing pathogen antigens can be used as live oral vaccines to immunize broilers against infectious diseases.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Vacinas Bacterianas/genética , Galinhas/microbiologia , Lactobacillus/genética , Lactobacillus/metabolismo , Probióticos/administração & dosagem , Administração Oral , Animais , Proteínas de Bactérias/administração & dosagem , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/administração & dosagem , Vacinas Bacterianas/imunologia , Doenças das Aves/imunologia , Doenças das Aves/microbiologia , Doenças das Aves/prevenção & controle , Galinhas/imunologia , Melhoramento Genético/métodos , Lactobacillus/imunologia , Lactobacillus/isolamento & purificação , Engenharia de Proteínas/métodos , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Transformação Bacteriana/genética
19.
J Med Entomol ; 40(2): 206-14, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12693850

RESUMO

Immunosuppression of house finches was attempted by blood feeding Culex tarsalis Coquillett mosquitoes or by injecting birds with the corticosteroid dexamethasone or the immunosuppressant drug cyclophosphamide before and after inoculation with western equine encephalomyelitis or St. Louis encephalitis viruses. Mosquito bites (8-37 females blood feeding on each bird over a 3-d period) did not enhance the viremia response or increase the frequency of chronic infection. In contrast, dexamethasone and cyclophosphamide enhanced the amplitude and duration of the viremia response, but had no consistent effect on the antibody responses as measured by enzyme immunoassay or plaque reduction neutralization assay. Elevated viremias were followed by increases in the frequency of chronic infections with St. Louis encephalitis, but not western equine encephalomyelitis. Immunosuppression may provide a useful tool to study the chronic infection process of flaviviruses in vertebrates.


Assuntos
Doenças das Aves/virologia , Culex/virologia , Vírus da Encefalite/isolamento & purificação , Encefalite/veterinária , Aves Canoras/imunologia , Aves Canoras/virologia , Animais , Doenças das Aves/imunologia , Doenças das Aves/prevenção & controle , Primers do DNA , Encefalite/imunologia , Encefalite/prevenção & controle , Vírus da Encefalite/genética , Vírus da Encefalite/imunologia , Feminino , Terapia de Imunossupressão/métodos , Masculino , Reação em Cadeia da Polimerase , Viremia/imunologia , Viremia/prevenção & controle , Viremia/veterinária
20.
Rev Sci Tech ; 15(1): 267-87, 1996 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8924710

RESUMO

The author summarises the occurrence of major diseases in wild animals maintained in captivity in South America. The epidemiology, impact and significance of the diseases are discussed, together with appropriate husbandry practices to control and prevent transmissible diseases. The following animal groups and pathologies are considered in this review: poxvirus dermatitis, gastroenteritis, pneumonia, amoebosis and coccidiosis in reptiles, management practices and diseases (including botulism, bacterial enteritis, psittacosis, aspergillosis and parasitic diseases in birds), enterocolitis, pneumonias and internal parasites in non-human primates, canine distemper, parvoviruses, babesiosis, internal and external parasites in carnivores, tuberculosis and enteritis in tapirs, haemorrhagic disease in cervids.


Assuntos
Criação de Animais Domésticos , Animais de Zoológico , Doenças Transmissíveis/veterinária , Animais , Doenças das Aves/epidemiologia , Doenças das Aves/prevenção & controle , Aves , Carnívoros , Controle de Doenças Transmissíveis , Doenças Transmissíveis/epidemiologia , Cervos , Perissodáctilos , Doenças dos Primatas/epidemiologia , Doenças dos Primatas/prevenção & controle , Primatas , Répteis , América do Sul/epidemiologia
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