834 resultados para AVIAN TRYPANOSOMES
Resumo:
Chlamydophila psittaci (C. psittaci) has been detected in 460 avian species, among them the most frequent are the Psittaciformes, Columbiformes, Anseriformes and raptors. In Brazil, the main avian species recognized as healthy carriers belong to the order Psittaciformes and Columbiformes, but very few studies have been done in other bird families. Reports of the occurrence of this disease in the clinical form are rare in the Ramphastids; consequently, they are not commonly evaluated for this agent. The present study reports the investigation of C. psittaci in 25 captive ramphastids from a zoological park in Sao Paulo State, Brazil. Swabs samples from the cloaca were submitted to semi-nested polymerase chain reaction (semi-nested PCR) for direct detection of the microorganism. Additionally, blood samples obtained from these birds were submitted to the Complement Fixation Test (CFT) for detection of antibodies anti-C. psittaci. The presence of C. psittaci was not detected in the cloacal swab samples tested by the PCR. Nevertheless, 16% (4/25) of the bird's sera were positive by the CFT. Among the species with positive results, there are the saffron toucanet (Pteroglossus bailloni) and black-necked-aracari (Pteroglossus aracari), two species with no descriptions of the survey of C. psittaci published in the literature. Intermittent elimination of C. psittaci is a feature of chronically infected birds; however the absence of a positive-antigen sample did not guarantee that the bird is Chlamydophila-free. The serological results obtained show that the ramphastids tested were previously exposed to the pathogen and developed immune response, but showed no clinical signs of the disease and didn't eliminate regularly the organism in their feces in the moment of the sample collection.
Resumo:
Cypermethrin dust was evaluated as a tool for the integrated management of lesser mealwonns (also called the darkling beetle), Alphitobius diaperinus (Panzer). This experiment examined the efficacy of the cypermethrin against adult and late instar lesser mealwonns under laboratory conditions. Two bioassay methods were evaluated, using either a petri plate or a covered plastic container simulating poultry house conditions. In the simulated conditions, two different samples were used and cypermethrin was either dusted onto the surface of the container or was directly dusted onto the bottom. The LC50 for adults was 636.6 ppm, however, 929.7 ppm of cypermethrin dust was needed to achieve a 50% mortality rate in late instar larvae 24 h after the administration of the insecticide. A similar trend was observed in the simulated poultry houses when the adult mortality was > 90% while effectiveness in late in. star larvae was decreased, i.e., between 50 and 85%. Significant differences in the toxicity profiles were observed in larvae mortality when cypermethrin it was dusted directly onto the litter surface, compared to the bottom of the container. We have verified that cypermethrin dust is available for use in poultry houses however, toxicity profiles of lesser mealworm may depend on the beetle's stage of development and method of application
Resumo:
The emergence of new infectious bronchitis virus (IBV) genotypes or serotypes along with the poor cross-protection observed among IBV serotypes have complicated the avian infectious bronchitis (IB) control programs in different geographic regions. In Cuba, the lack of genetic information regarding IBV and the increasing epidemiological importance of this virus in Cuban chicken flocks demand further characterization of IBV isolates. In the present work, studies of genetic diversity and phylogenetic relationships among recent IBV isolates from Cuban chicken flocks showing respiratory disorders were performed. Two putative genotypes genetically different to the Massachusetts genotype H120 strain used in the Cuban vaccination program were found in the flocks assessed. In addition, a potential nephropathogenic IBV isolate was found by first time in Cuba. (C) 2012 Elsevier Ltd. All rights reserved.
Resumo:
The water vapor conductance (G(H20)) of the neosauropod eggs from the Lower Cretaceous Sanagasta nesting site in La Rioja Province, Argentina, was examined and compared with other Cretaceous Argentinean oological material. The 2900 mgH(2)O/day.Torr G(H2O) of the Sanagasta eggshells confirms an extremely moist nesting environment and supports field observations of dug-out nests in a geothermal setting. The observed thinning of the outer eggshell surface during incubation increases gas conductance and concomitantly decreases eggshell mechanical resistance during the late ontogenetic stages, thus facilitating embryonic development and hatching. The Sanagasta and Entre Rios Province faveoloolithid eggs display the highest and comparable 61120 values and share several morphological and diagenetic characters, indicating comparable nesting strategy in geothermal settings. However, the faveoloolithid Yamintie and La Pampa Province specimens cluster together with lower G(H20) values closer to the megaloolithid eggs. The Gnu) of the megaloolithid egg Megaloolithus patagonicus was reconsidered and new results are now congruent with other reported megaloolithid GH2O values. Additionally, we hypothesize that V-shaped pore canals of M. patagonicus, which upper sections reach only the top third or half eggshell thickness and, a wider section in the middle would not compromise the overall egg mechanical resistance like vertical pores connecting directly the outer to the inner eggshell surfaces. Such pore spatial arrangement and geometry would enhance, as the eggshell thins during incubation, a greater G(H2O), G(O2) and G(CO2) and facilitate embryonic development in high moisture nesting contents. Overall, data suggests that neosauropod nesting and brooding behaviors were dependent on elevated moisture nesting environments.
Resumo:
A VDAC é uma porina presente na MME cuja função é crucial no metabolismo energético, sobrevivência e morte celular. A caracterização da VDAC torna-se importante para a compreensão das inter-relações da mitocôndria com os diferentes componentes citosólicos, tais como a HK. A ligação HK-VDAC favorece a utilização do ATP intramitocondrial em células neuronais, a HK cerebral pode interagir de formas diferentes com a VDAC, o que resulta em diferentes sítios de ligação (sítios A e B). Os variados papéis metabólicos das isoformas da VDAC podem ser explicados pela presença de alterações pós-traducionais. No presente trabalho purificamos a VDAC1 mitocondrial neuronal proveniente de cérebro aviar. Paralelamente, comprovamos que a presença de múltiplas formas das VDACs 1 e 2 em cérebros murino e aviar, seja devida à presença de modificações pós-traducionais, nomeadamente a fosforilação. A proteína isolada apresentou peso molecular de 30KDa. Quando submetida à eletroforese e posteriormente à coloração para a identificação de fosfoproteínas, a mesma mostrou-se desfosforilada. O conhecimento da presença, ou ausência de fosforilação das VDACs, reside na importância de estabelecer-se as bases moleculares ligadas à existência de sítios A e B nas mitocôndrias neuronais.
Resumo:
Brazil is one of the world's largest countries with a rich diversity of wildlife, including resident and migratory wild birds, which may be natural reservoirs of the Newcastle disease virus (NDV). Because Brazil is a major global exporter of chicken meat, the emergence of such a disease may have a huge negative impact not only on the economy due to trade restrictions and embargoes, but also on the quality of life of the population. Samples were collected from 1,022 asymptomatic domestic and wild birds from the Brazilian coast and the Amazon region using tracheal/cloacal swabs and tested by RT-qPCR. The results showed 7 (0.7%) birds were positive for NDV. The positive samples were then isolated in embryonated chicken eggs and their matrix protein genes were partially sequenced, revealing a low-pathogenicity NDV. This study confirms the maintenance of the velogenic-NDV free status of Brazil.
Resumo:
The hyacinth macaw (Anodorhyncus hyacinthinus), considered the largest psittacine bird species in the world, is an endangered species, with a remaining population of approximately 6500 birds in the wild. To establish hematologic and plasma biochemical reference ranges and to verify differences related to sex, samples from 29 hyacinth macaws (14 males. 15 females) were obtained from birds apprehended from illegal wildlife trade and subsequently housed at the Sorocaba Zoo, Brazil. No significant differences in hematologic or plasma biochemical values were found between females and males. Compared with published reference values, differences were found in mean concentrations of total red blood cell count, corpuscular volume, corpuscular hemoglobin level, total white blood cell count, aspartate aminotransferase level, creatine kinase concentration, alkaline phosphatase concentration, and phosphorus level. Baseline hematologic and plasma biochemical ranges were established, which may be useful as reference values for clinicians working with this endangered species in captivity or rehabilitation centers.
Resumo:
Golden conures or ararajubas (Guaruba guarouba) are endangered parrots endemic to the Brazilian Amazon forest. Body mass, blood cell counts, and total plasma protein were determined for 70 clinically healthy golden conures captive at zoologic parks and private breeder facilities in Brazil. Hematologic results (mean +/- SD) were: Erythrocytes 3.6 +/- 0.5 x 10(6) cells/mm(3), hemoglobin 12.8 +/- 1.4 g/dl, packed cell volume 46 +/- 3.8%, mean corpuscular volume 132 +/- 20 fl, mean corpuscular hemoglobin (MCH) 36 +/- 5.7 pg, mean corpuscular hemoglobin concentration (MCHC) 28 +/- 3.5%, thrombocytes 26.3 +/- 9.3 x 10(3) cells/mm(3), leukocytes 11.9 +/- 4.5 x 10(3) cells/mm(3), heterophils 6284 +/- 2715 cells/mm(3), lymphocytes 5473 +/- 2408 cells/mm(3), monocytes 113 +/- 162 cells/mm(3), eosinophils 10 +/- 42 cells/mm(3), basophils 27 +/- 64 cells/mm(3). Body mass was 254 +/- 24.9 g and total plasma protein (TPP) was 3.54 +/- 0.58 g/dl. No statistical differences were observed between genders within age groups. Differences between juveniles (J) and adults (A) were identified for TPP < A), MCH (J > A), and MCHC (J > A). These results provide reliable reference values for the clinical interpretation of hematologic results for the species. Hematology may be an important tool for population health investigations on free-ranging golden conure populations and will also be essential to survey the health of release candidates in future reintroduction programs.
Resumo:
A new chewing louse genus and species belonging to the Philopteridae, namely, Palmaellus inespectatus n. gen., n. sp., is described. The new genus is distinguished from the other ischnoceran genera hitherto described by its peculiar characters of the dorsal anterior head plate with 2 postero-lateral projections, pterothorax and abdomen with scarce chaetotaxy, male genitalia with simple mesomere and paramere lacking inner digitiform projection, and the genital region of female with postero-vulvar plates bearing setae. It is a parasite of the trumpeters, an avian family endemic to South America's Amazon Basin.
Resumo:
Trypanosoma cruzi, the agent of Chagas disease, is a complex of genetically diverse isolates highly phylogenetically related to T. cruzi-like species, Trypanosoma cruzi marinkellei and Trypanosoma dionisii, all sharing morphology of blood and culture forms and development within cells. However, they differ in hosts, vectors and pathogenicity: T. cruzi is a human pathogen infective to virtually all mammals whilst the other two species are non-pathogenic and bat restricted. Previous studies suggest that variations in expression levels and genetic diversity of cruzipain, the major isoform of cathepsin L-like (CATL) enzymes of T. cruzi, correlate with levels of cellular invasion, differentiation, virulence and pathogenicity of distinct strains. In this study, we compared 80 sequences of genes encoding cruzipain from 25 T. cruzi isolates representative of all discrete typing units (DTUs TcI-TcVI) and the new genotype Tcbat and 10 sequences of homologous genes from other species. The catalytic domain repertoires diverged according to DTUs and trypanosome species. Relatively homogeneous sequences are found within and among isolates of the same DTU except TcV and TcVI, which displayed sequences unique or identical to those of TcII and TcIII, supporting their origin from the hybridization between these two DTUs. In network genealogies, sequences from T. cruzi clustered tightly together and closer to T. c. marinkellei than to T. dionisii and largely differed from homologues of T. rangeli and T. b. brucei. Here, analysis of isolates representative of the overall biological and genetic diversity of T. cruzi and closest T. cruzi-like species evidenced DTU- and species-specific polymorphisms corroborating phylogenetic relationships inferred with other genes. Comparison of both phylogenetically close and distant trypanosomes is valuable to understand host-parasite interactions, virulence and pathogenicity. Our findings corroborate cruzipain as valuable target for drugs, vaccine, diagnostic and genotyping approaches.
Resumo:
Birds are the most diverse and largest group of extant tetrapods. They show marked variability, yet much of this variation is superficial and due to feather and bill color and shape. Under the feathers, the skeleto-muscular system is rather constant throughout the bird group. The adaptation to flight is the explanation for this uniformity. The more obvious morphological adaptations for flight are the wings, but the trunk is always rigid, the tail is short and the neck is flexible, since all these features are correlated with flying behaviour. Unrelated to the exigencies of flight, the legs always have three long bones, and all the birds walk on their toes. This leg structure is a striking plesiomorphic feature that was already present in related dinosaurs. The multi-purpose potential of the legs is the result of the skeletal architecture of a body with three segmented flexed legs. This configuration provides mechanical properties that allow the use of the legs as propulsive, paddling, foraging or grooming tools. It is the association of diverse modes of locomotion-walking, running, hopping, flying and swimming-that have enabled the birds to colonize almost all the environments on Earth.
Resumo:
This study evaluated for the first time the life cycle of Amblyomma ovale in the laboratory. For this purpose, larvae and nymphs were exposed to Gallus gallus (chickens), Cavia porcellus (guinea pigs), Rattus norvegicus (wistar rats), Oryctolagus cuniculus (domestic rabbits), Calomys callosus (vesper mouse), and Didelphis albiventris (white-eared opossum). Nymphs were also exposed to Nectomys squamipes (South American water rat). Adult ticks were fed on dogs. The life-cycle of A. ovale in laboratory could be completed in an average period of ca. 190 days, considering prefeeding periods of 30 days for each of the parasitic stages. Vesper mice were the most suitable host for A. ovale larvae, whereas water rats were the most suitable host for A. ovale nymphs. Our results, coupled with literature data, strongly indicate that small rodents have an important role in the life history of A. ovale. Chickens (the only avian host used in the present study) showed to be moderately suitable hosts for subadult A. ovale ticks, indicating that wild birds might have a secondary role in the life history of A. ovale. Domestic dogs showed to be highly suitable for the adult stage of A. ovale, in agreement with literature data that indicate that the domestic dog is currently one of the most important hosts of A. ovale adult ticks in Latin America.
Resumo:
Anti-silencing factor 1 (ASF1) is a histone chaperone that contributes to the histone deposition during nucleosome assembly in newly replicated DNA. It is involved in chromatin disassembly, transcription activation and in the cellular response to DNA damage. In Leishmania major the ASF1 gene (LmASF1) is located in chromosome 20 and codes for a protein showing 67% of identity with the Trypanosoma brucei TbASF1a. Compared to orthologous proteins, LmASF1 conserves the main residues relevant for its various biological functions. To study ASF1 in Leishmania we generated a mutant overexpressing LmASF1 in L. major. We observed that the excess of LmASF1 impaired promastigotes growth rates and had no impact on cell cycle progress. Differently from yeast, ASF1 overproduction in Leishmania did not affect expression levels of genes located on telomeres, but led to an upregulation of proteins involved in chromatin remodelling and physiological stress, such as heat shock proteins, oxidoreductase activity and proteolysis. In addition, we observed that LmASF1 mutant is more susceptible to the DNA damaging agent, methyl methane sulphonate, than the control line. Therefore, our study suggests that ASF1 from Leishmania pertains to the chromatin remodelling machinery of the parasite and acts on its response to DNA damage.
Resumo:
Stressful situations reduce the welfare, production indices and immune status of chickens. Salmonella spp. are a major zoonotic pathogens that annually cause over 1 billion infections worldwide. We therefore designed the current experiment to analyse the effects of 31 +/- 1 degrees C heat stress (HS) (from 35 to 41 days) on performance parameters, Salmonella invasion and small intestine integrity in broiler chickens infected with Salmonella Enteritidis. We observed that HS decreased body weight gain and feed intake. However, feed conversion was only increased when HS was combined with Salmonella Enteritidis infection. In addition, we observed an increase in serum corticosterone levels in all of the birds that were subjected to HS, showing a hypothalamus-pituitary-adrenal axis activation. Furthermore, mild acute multifocal lymphoplasmacytic enteritis, characterized by foci of heterophil infiltration in the duodenum, jejunum and ileum, was observed in the HS group. In contrast, similar but more evident enteritis was noted in the heat-stressed and Salmonella-infected group. In this group, moderate enteritis was observed in all parts of the small intestine. Lastly, we observed an increase in Salmonella counts in the spleens of the stressed and Salmonella-infected chickens. The combination of HS and Salmonella Enteritidis infection may therefore disrupt the intestinal barrier, which would allow pathogenic bacteria to migrate through the intestinal mucosa to the spleen and generate an inflammatory infiltrate in the gut, decreasing performance parameters.
Resumo:
mitochondrial genomes are generally thought to be under selection for compactness, due to their small size, consistent gene content, and a lack of introns or intergenic spacers. As more animal mitochondrial genomes are fully sequenced, rearrangements and partial duplications are being identified with increasing frequency, particularly in birds (Class Ayes). In this study, we investigate the evolutionary history of mitochondrial control region states within the avian order Psittaciformes (parrots and cockatoos). To this aim, we reconstructed a comprehensive multi-locus phylogeny of parrots, used PCR of three diagnostic fragments to classify the mitochondrial control region state as single or duplicated, and mapped these states onto the phylogeny. We further sequenced 44 selected species to validate these inferences of control region state. Ancestral state reconstruction using a range of weighting schemes identified six independent origins of mitochondrial control region duplications within Psittaciformes. Analysis of sequence data showed that varying levels of mitochondrial gene and tRNA homology and degradation were present within a given clade exhibiting duplications. Levels of divergence between control regions within an individual varied from 0-10.9% with the differences occurring mainly between 51 and 225 nucleotides 3' of the goose hairpin in domain I. Further investigations into the fates of duplicated mitochondrial genes, the potential costs and benefits of having a second control region, and the complex relationship between evolutionary rates, selection, and time since duplication are needed to fully explain these patterns in the mitochondrial genome. (C) 2012 Elsevier Inc. All rights reserved.