RESUMO
In this review, diagnostic techniques and viral agents involved in enteric diseases affecting turkeys are described. Data from field observations and laboratory researches have been reported in turkey flocks for over 70 years, and several viruses have been identified. After a period of 30 years of inoculation experiments and neutralization studies, adequate visualization of the viruses was achieved using electronic microscopy. During the following years, several studies were then conducted to isolate and classify those viruses using cell-culture, embryo-propagation, serological tests, genome electropherotyping by polyacrylamide gel electrophoresis of double-stranded RNA viruses, and recently, nucleic acid studies. Thus, since the 1990s, the nucleic-acid technology has focused on genomic surveys and on the detection of specific segments of the genome of each virus using the polymerase-chain reaction, resulting in several prevalence studies and phylogenetic analyses of different isolates and proper classification of the viruses.(AU)
Assuntos
Animais , Peru , Coronavirus do Peru/classificação , Enterite Transmissível dos Perus/classificação , Enterite Transmissível dos Perus/diagnóstico , Enterite Transmissível dos Perus/históriaRESUMO
In this review, diagnostic techniques and viral agents involved in enteric diseases affecting turkeys are described. Data from field observations and laboratory researches have been reported in turkey flocks for over 70 years, and several viruses have been identified. After a period of 30 years of inoculation experiments and neutralization studies, adequate visualization of the viruses was achieved using electronic microscopy. During the following years, several studies were then conducted to isolate and classify those viruses using cell-culture, embryo-propagation, serological tests, genome electropherotyping by polyacrylamide gel electrophoresis of double-stranded RNA viruses, and recently, nucleic acid studies. Thus, since the 1990s, the nucleic-acid technology has focused on genomic surveys and on the detection of specific segments of the genome of each virus using the polymerase-chain reaction, resulting in several prevalence studies and phylogenetic analyses of different isolates and proper classification of the viruses.
Assuntos
Animais , Coronavirus do Peru/classificação , Enterite Transmissível dos Perus/classificação , Enterite Transmissível dos Perus/diagnóstico , Enterite Transmissível dos Perus/história , PeruRESUMO
Bordetella avium is an opportunistic pathogen that presents tropism for ciliated epithelia, leading to upper respiratory tract disease in turkeys. This agent has also been associated with Lockjaw Syndrome in psittacine birds, but literatures describing the importance of this agent in such species are rare. The purpose of the present study was to report the first outbreak of B. avium infection in juvenile cockatiels demonstrating the Lockjaw Syndrome in Brazil and to investigate the antimicrobial resistance profile and phenotypic and genotypic characteristics of these strains. Surprising, the strains obtained from five infected cockatiel chicks from three different breeders from different Brazilian states showed a clonal relationship using the Pulsed Field Gel Electrophoresis and Single Enzyme Amplified Fragment Length Polymorphism techniques. The virulence potentials of the B. avium strains were assessed using tracheal adherence and cytotoxic effects on a VERO cell monolayer.
Assuntos
Doenças das Aves/microbiologia , Infecções por Bordetella/veterinária , Bordetella avium/genética , Bordetella avium/patogenicidade , Cacatuas/microbiologia , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Antibacterianos/farmacologia , Infecções por Bordetella/microbiologia , Bordetella avium/efeitos dos fármacos , Brasil , Chlorocebus aethiops , Farmacorresistência Bacteriana , Eletroforese em Gel de Campo Pulsado , Genótipo , Turquia , Células VeroRESUMO
The effects in broiler chicks of treatment with a competitive exclusion (CE) product, an experimental dietary probiotic, and the abiotic beta-glucan on cecal colonization, organ invasion, and serum and intestinal IgG and IgA levels to Salmonella challenge was evaluated. Four groups of 1-d-old chicks were treated by oral gavage on d 1 with an appropriate dose of a commercial CE product. Three groups received daily doses of probiotic, beta-glucan, or both, for 6 d. Three other groups were fed daily from d 1 onwards with probiotic, beta-glucan, or both. Subgroups of 30 chicks from each group were challenged on d 1, 9, 16, or 23 with 10(7) cfu/ mL of Salmonella Typhimurium (1769NR) and killed 7 d later. Control groups were maintained untreated and remained unchallenged (negative control), or were challenged with Salmonella Typhimurium (1769NR; positive control), as described above. Cecum, liver, and spleen samples were examined for the presence of Salmonella, whereas serum and intestinal fluid samples were assayed for total antibody (IgG and IgA) concentrations. Data were analyzed by 1-way ANOVA, and means were compared using Duncan's multiple range test. In comparison with other treatments, those involving CE product and beta-glucan, with or without probiotic during the first week, resulted in a superior inhibition of cecal colonization and organ invasion by Salmonella and also offered a higher level of protection (P < 0.05). During the second week, treatments containing experimental dietary probiotic and beta-glucan, with or without CE product, resulted in an inhibition of liver invasion (P < 0.05). The IgA levels were significantly higher (P < 0.05) in intestinal fluid compared with serum, whereas IgG had low levels. The results in the first and third week indicate that combination treatments involving CE product, probiotic, and beta-glucan are a more effective control of Salmonella colonization than the corresponding individual preparations.
Assuntos
Galinhas , Doenças das Aves Domésticas/prevenção & controle , Probióticos/uso terapêutico , Salmonelose Animal/prevenção & controle , Salmonella typhimurium , beta-Glucanas/uso terapêutico , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ceco/microbiologia , Dieta/veterinária , Imunoglobulina A/sangue , Lactobacillus , Salmonelose Animal/microbiologiaRESUMO
In this study, a new competitive-exclusion (CE) product, Mucosal Starter Culture (MSC), was compared with two other CE products (Aviguard and Avifree) commercially available in Brazil to evaluate their ability to protect newly hatched chicks against colonization by a strain of Salmonella Kedougou. This study was based on a previously published and recommended method for such products. Separate groups of the chicks were dosed orally with the respective treatment materials and challenged 24 h later, and their ceca were examined for Salmonella 5 days after challenge. Under the test conditions, only MSC and Aviguard gave statistically significant (P < 0.05) protection to the chicks, but the MSC treatment yielded the lowest mean level of cecal carriage and the smallest proportion of Salmonella-positive birds.
Assuntos
Galinhas , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/prevenção & controle , Salmonella/crescimento & desenvolvimento , Animais , Brasil , Ceco/microbiologia , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologiaRESUMO
Hamsters inoculated with BCG become responsive to dead Mycobacterium leprae. The response is characerized by a typical perineural granulomatous reaction, observed 16 days after the injection of a suspension of dead M. leprae into the foot pad of animals previously sensitized with BCG