Lipid and glucose metabolism of broilers (Gallus gallus domesticus) experimentally infected with Eimeria acervulina Tyzzer, 1929 oocysts

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Aspectos clínicos e patológicos em frangos de corte (Gallus gallus domesticus) infectados experimentalmente com oocistos esporulados de Eimeria acervulina Tyzzer, 1929

No presente estudo, sinais clínicos e alterações patológicas foram avaliados por 30 dias em frangos de corte, linhagem Cobb, machos, com dez dias de idade, infectados com Eimeria acervulina. Foram utilizados 192 animais distribuídos em 3 grupos: grupo A inoculado com 1x10(6) oocistos esporulados; grupo B inoculado com 1x10(5) oocistos esporulados; grupo C inoculado com água destilada. Os sinais clínicos observados foram anorexia, diarréia e apatia. As alterações patológicas macroscópicas observadas foram: enterite, hiperemia seguido de congestão intestinal, excesso de exsudato mucoso no lúmen do intestino delgado, palidez e desidratação muscular, alto acúmulo de bile na vesícula biliar e deposição de gordura hepática. A atrofia de vilosidades e alta presença de células inflamatórias foram as alterações microscópicas observadas no epitélio intestinal. Na análise histopatológica do fígado observaram-se infiltrados inflamatórios e deposição de gordura. Os resultados demonstraram que frangos de corte infectados experimentalmente com E. acervulina apresentam progressivas lesões intestinais de intensidade variável e que essas anormalidades são as principais causas de redução no desenvolvimento da ave.

In vivo effects of chicken interferon-gamma during infection with Eimeria

Newly hatched chickens are highly susceptible to infection by opportunistic pathogens during the first 1 or 2 weeks of life, The use of cytokines as therapeutic agents has been studied in animal models as well as in immunosuppressed patients, This approach has become more feasible in livestock animals, in particular poultry, with the recent cloning of cytokine genes and the development of new technologies, such as live delivery vectors, We have recently cloned the gene for chicken interferon-gamma (Ch-IFN-gamma), Poly-HIS-tagged recombinant Ch-IFN-gamma was expressed in Escherichia coil, was purified by Ni chromatography, and was found to be stable at 4 degrees C and an ambient temperature for at least several months and Several weeks, respectively, Ch-IFN-gamma was capable of protecting chick fibroblasts from undergoing virus-mediated lysis, induced nitrite secretion from chicken macrophages in vitro, and enhanced MHC class II expression on macrophages, Administration of recombinant Ch-IFN-gamma to chickens resulted in enhanced weight gain over a 12-day period, Furthermore, the therapeutic potential of Ch-IFN-gamma was assessed using a coccidial challenge model, Birds were treated with Ch-IFN-gamma or a diluent control and then infected with Eimeria acervulina. Infected birds treated with Ch-IFN-gamma showed improved weight gain relative to noninfected birds, The ability of Ch-IFN-gamma to enhance weight gain in the face of coccidial infection makes it an excellent candidate as a therapeutic agent.

Óleo essencial de orégano, alecrim, canela e extrato de pimenta no controle de Salmonella, Eimeria e Clostridium em frangos de corte

Este trabalho foi conduzido com o objetivo de avaliar a eficiência de um composto vegetal contendo óleo essencial de orégano, alecrim, canela e extrato de pimenta vermelha no controle de Salmonella, Eimeria e Clostridium em frangos de corte. Para tal, foram realizados dois experimentos. No primeiro avaliou-se a eficiência deste produto no controle de Clostridium perfringens após desafio com Eimeria acervulina, E. maxima e E. tenella. Aves de um dia de idade foram divididas em três grupos: T1 - dieta controle sem aditivo promotor de crescimento; T2 - dieta com adição de avilamicina (10ppm); e T3 - dieta com adição do composto vegetal (100ppm). O uso do composto vegetal na alimentação de frangos reduziu lesões específicas de E. maxima e E. tenella aos 14 dias pós-inoculação (PI) como também reduziram a contagem de unidades formadoras de colônias (UFC) de Clostridium perfringens no conteúdo do ceco das aves em relação ao grupo controle. No segundo experimento avaliou-se a eficiência deste mesmo produto em aves desafiadas com Salmonella Enteritidis. Aves de um dia de idade foram distribuídas em três tratamentos, sendo T1 - dieta controle sem adição de antibiótico promotor de crescimento, T2 - dieta com 10ppm de Avilamicina, T3 - dieta com 100ppm de um produto a base do composto vegetal acima citado. Aos 21 dias de idade todas as aves foram inoculadas com 10(5) UFC de Salmonella Enteritidis. A utilização do composto vegetal e avilamicina diminuiu a excreção de Salmonella nas aves 72 horas PI de Salmonella. A utilização do composto vegetal aumentou a relação vilo/células CD3+ no duodeno, em relação ao grupo avilamicina e controle, porém não teve efeito sobre a expressão destas células no ceco.

A comparative transcriptome analysis reveals expression profiles conserved across three Eimeria spp. of domestic fowl and associated with multiple developmental stages

Coccidiosis of the domestic fowl is a worldwide disease caused by seven species of protozoan parasites of the genus Eimeria. The genome of the model species, Eimeria tenella, presents a complexity of 55-60 MB distributed in 14 chromosomes. Relatively few studies have been undertaken to unravel the complexity of the transcriptome of Eimeria parasites. We report here the generation of more than 45,000 open reading frame expressed sequence tag (ORESTES) cDNA reads of E. tenella, Eimeria maxima and Eimeria acervulina, covering several developmental stages: unsporulated oocysts, sporoblastic oocysts, sporulated oocysts, sporozoites and second generation merozoites. All reads were assembled to constitute gene indices and submitted to a comprehensive functional annotation pipeline. In the case of E. tenella, we also incorporated publicly available ESTs to generate an integrated body of information. Orthology analyses have identified genes conserved across different apicomplexan parasites, as well as genes restricted to the genus Eimeria. Digital expression profiles obtained from ORESTES/EST countings, submitted to clustering analyses, revealed a high conservation pattern across the three Eimeria spp. Distance trees showed that unsporulated and sporoblastic oocysts constitute a distinct clade in all species, with sporulated oocysts forming a more external branch. This latter stage also shows a close relationship with sporozoites, whereas first and second generation merozoites are more closely related to each other than to sporozoites. The profiles were unambiguously associated with the distinct developmental stages and strongly correlated with the order of the stages in the parasite life cycle. Finally, we present The Eimeria Transcript Database (http://www.coccidia.icb.usp.br/eimeriatdb), a website that provides open access to all sequencing data, annotation and comparative analysis. We expect this repository to represent a useful resource to the Eimeria scientific community, helping to define potential candidates for the development of new strategies to control coccidiosis of the domestic fowl. (C) 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.

Ação trófica de aditivos fitogênicos, glutamina e ácido glutâmico sobre a Bursa de Fabrícius e intestino delgado de frangos de corte

Abstract The aim of this study was to evaluate the effect of phytogenic additives and glutamine plus glutamic acid, associated or not, on histomorphometry of bursa of Fabricius and small intestine, oocyst count and lesion scores, and carbon turnover of duodenal mucosa of broiler chickens infected with Eimeria acervulina. A total of 450 male broiler chickens was distributed into a completely randomized design with six treatments and three replications. Treatments consisted of control diet (CD); CD + coccidiosis vaccine; CD + antibiotic performance enhancers and anticoccidial (APE/AC); CD + glutamine and glutamic acid (Gln/Glu); CD + phytogenic additives (PA); CD + Gln/Glu + PA. Birds on treatment CD + vaccine were vaccinated via drinking water at three days of age against coccidiosis. At 16 days of age all birds of all treatments were inoculated orally and individually with 500,000 oocysts of Eimeria acervulina. There was no treatment effect on lesion score in the intestinal epithelium of birds. The smaller number of excreted oocysts was observed in groups of birds fed diets containing APE/AC and PA. Were observed better results of villus height and crypt depth for duodenum and ileum of birds of treatments containing Gln/Glu at 7 days of age, and Gln/Glu and PA at 21 days of age. Higher percentage of cortical area from bursa follicles was observed in birds fed diets supplemented with Gln/Glu and PA at 7, 14 and 21 days of age. Increased turnover of intestinal mucosa was observed in treatments containing Gln/Glu, indicating acceleration in development and regeneration of damaged tissue. Glutamine plus glutamic acid and phytogenic additives can provide improvements to structure, and thus to intestinal function, as well as to better immune response against the infectious challenges. Phytogenic additives can be used for coccidiosis control of broiler chickens where the use of antibiotic performance enhancers and anticoccidials is prohibited.

Nucleotídeos na dieta de frangos de corte e seus efeitos sobre taxa de turnover da mucosa intestinal antes e após lesões causadas por coccidiose

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Structural biology of membrane-acting peptides: Conformational plasticity of anticoccidial peptide PW2 probed by solution NMR

The bottleneck for the complete understanding of the structure-function relationship of flexible membrane-acting peptides is its dynamics. At the same time, not only the structure but also the dynamics are the key points for their mechanism of action. Our model is PW2, a TRP-rich, cationic peptide selected from phage display libraries that shows anticoccidial activity against Eimeria acervulina. In this manuscript we used a combination of several NMR techniques to tackle these difficulties. The structural features of the membrane-acting peptide PW2 was studied in several membrane mimetic environments: we compared the structural features of PW2 in SDS and DPC micelles, that were reported earlier, with the structure properties in different lipid vesicles and the peptide free in water. We were able to unify the structural information obtained in each of these systems. The structural constraints of the peptide free in water were fundamental for the understanding of plasticity necessary for the membrane interaction. Our data suggested that the WWR sequence is the region responsible for anchoring the peptide to the interfaces, and that this same region displays some degree of conformational order in solution. For PW2, we found that affinity is related to the aromatic region, by anchoring the peptide to the membrane, and specificity is related to the N- and C-termini, which are able to accommodate in the membrane due to its plasticity. (C) 2007 Elsevier B.V. All rights reserved.

Ácidos orgânicos isolados ou associados em dietas de frangos de corte

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Probiótico e ácidos orgânicos na alimentação inicial de frangos de corte: Desempenho zootécnico, morfometria e microbiologia intestinal

Pós-graduação em Ciência e Tecnologia Animal - FEIS

Imunonutrição de frangos de corte alimentados com ácidos orgânicos em alternativa aos quimioterápicos

Pós-graduação em Ciência e Tecnologia Animal - FEIS

High-resolution electrophoretic procedures for the identification of five Eimeria species from chickens, and detection of population variation

To overcome limitations of conventional approaches for the identification of Eimeria species of chickens, we have established high resolution electrophoretic procedures using genetic markers in ribosomal DNA. The first and second internal transcribed spacer (ITS-1 and ITS-2) regions of ribosomal DNA were amplified by polymerase chain reaction (PCR) from genomic DNA samples representing five species of Eimeria (E. acervulina, E. brunetti, E. maxima, E. necatrix and E. tenella), denatured and then subjected to denaturing polyacrylamide gel electrophoresis (D-PAGE) or single-strand conformation polymorphism (SSCP) analysis. Differences in D-PAGE profiles for both the ITS-1 and ITS-2 fragments (combined with an apparent lack of variation within individual species) enabled the unequivocal identification of the five species, and SSCP allowed the detection of population variation between some isolates representing E. acervulina, which remained undetected by D-PAGE. The establishment of these approaches has important implications for controlling the purity of laboratory lines of Eimeria, for diagnosis and for studying the epidemiology of coccidiosis.

Eimeria vitellini n. sp. (Apicomplexa: eimeriidae) from the brazilian toucan Rhamphastos vitellinus vitellinus Lichtenstein (Aves: Picicformes: Rhamplastidae)

Eimeria vitellini n. sp. is described from the faeces of the Rhamphastos v. vitellinus. Oocysts broadly ellipsoidal to oval (egg-shaped), 22,6 x 18.3 (20.0-25.0 x 16.3-22.5) micronm, shapeindex (length/width) 1.2 (1.1-1.1). Oocyst wall a single colourless layer about 0.5 micronm thick, becoming thinner at one ectremity, at which point the oocyst usually ruptures. No oocyst residuum, but 1 or 2 small polr bodies of about 1.0-1.5 x 0.5-1.0 micronm. Sporocysts ellongated ellipsoid (pearshaped), 14.3 x 7.5 (13.8-15.0 x 6.9-7.5) micronm, shape-index (1.9 (1.8-2.0), with a thin colourless wall bearing a very delicate Stieda body: a conspicuous sub-Stieda body is present. Sporozoites with anterior and posterior regractile bodies and strongly recurved around a bulky, compact sporocyst residuum composed of relatively fine granules and spherules.

Eimeria species (Apicomplexa: Eimeriidae) of podocnemis expansa (Schweigger) and geochelone denticulata (LINN.) from Amazonian Brazil (Reptilia: Chelonia)

Eimeria lagunculata, Eimeria mammiformis and Eimeria podocnemis n. spp., are described from the faeces of the fresh-water turtle Podocnemis expansa, in Pará State, north Brasil. Oocysts of E. lagunculata are ellipsoidal, 19.2 x 12.8 (17.0-20.7 x 11.8-14.1) mum, shape-index (= length/ width) 1.5 (1.4-1.7). Oocyst wall about 0.5-0.7 mum thick, with a prominent stopper-like micropyle at one pole. No oocyst residuum and no polar body. Sporocysts elongate ellipsoidal, 11.0 x 5.4 (10.4-11.8 x 5.2-6.0) mum, shape-index 2.0 (1.8-2.1): no Stieda body. A compact, ellipsoidal sporocyst residuum lies between the two sporozoites, which possess a posterior and an anterior refractile body. Oocysts of E. mammiformis broadly ellipsoidal, 30.0 x 19.4 (23.0-37.0 x 16.3-21.5) mum, shape-index 1.5 (1.1-1.9). Oocyst wall about 0.7 mum thick, with a prominent micropyle: no oocyst residuum and rarely a single polar body. Sporocysts ellipsoidal, 15.3 x 7.9 (14.8-17.0 x 7.4-9.6) mum, shape-index 2.0 (1.8-2.2), with a tiny Stieda body. Sporocyst residuum bulky, ellipsoidal: sporozoites with two conspicuous refractile bodies. E. podocnemis has broadly ellipsoidal oocysts, 17.0 x 12.8 (14.8-19.2 x 11.8-14.1) mum, shape-index 1.3 (1.1-1.4). Oocyst wall about 0.5-0.7 mum thick, with no micropyle. No oocyst residuum, but always a single polar body. Sporocysts ellipsoidal, 9.7 x 5.2 (8.9-10.4 x 4.4-6.0) mum, shape-index 1.9 (1.6-2.0), with no Stieda body. Sporocyst residuum bulky, ellipsoidal: sporocysts with 2 refractile bodies. Eimeria carinii n. sp., is recorded from the tortoise Geochelone denticulata, also from Pará. Oocyst wall about 1.2 mum thicl. No micropyle. Oocyst residuum limited to a number (about 10-20) of scattered granules: no polar body. Sporocysts broadly ellipsoidal, and with no Stieda body: they measure 8,8 x 7.3 (8.0-9.0 x 7.0-7.5) mum, shape-index 1.2 (1.1-1.3). Sporocyst residuum bulky, spherical to ellipsoidal: sporozoites possess both posterior and anterior refractile bodies.