990 resultados para breeding birds


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Skeletal tissues of 49 humpback whales Megaptera novaeangliae that stranded between 2002 and 2011 along the Abrolhos Bank seashore and its adjacent waters in Brazil were studied. Twelve (24.5%) animals presented pathological changes in one or more bones. Degenerative changes and developmental malformations were most frequent (10.2% each), followed by inflammatory/infectious and traumatic lesions (8.2% each). Infectious diseases led to severe lesions of the caudal vertebrae of 2 whales. In one of these individuals, the lesions involved 6 caudal vertebrae, leading to ankylosis of 3 vertebrae. Degenerative changes were observed in the vertebral columns of 3 animals, involving the joints of 13 ribs of 1 individual, and in the humerus of 1 whale. Traumatic lesions, such as osseous callus in the ribs, were observed in 4 animals. In 1 whale, the rib showed severe osteomyelitis, possibly resulting from the infection of multiple fractures. Developmental abnormalities such as spina bifida on 3 cervical vertebrae of 1 whale, fusion of spinal processes on thoracic vertebrae of 1 individual and fusion of the first 2 ribs unilaterally or bilaterally in 4 animals were found. Chronic infectious conditions found in the axial skeleton may have restrained spinal mobility and had detrimental effects on the general health of the animals, contributing to stranding and death. To our knowledge, this is the first systematic study on skeletal lesions in stranded humpback whales.

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Risks of the introduction of highly pathogenic avian influenza (HPAI) H5N1 through migratory birds to the main wintering site for wild birds in southern Brazil and its consequences were assessed. Likelihoods were estimated by a qualitative scale ranging from negligible to high. Northern migrants that breed in Alaska and regularly migrate to South America (primary Charadriiformes) can have contact with birds from affected areas in Asia. The likelihood of the introduction of HPAI H5N1 through migratory birds was found to be very low as it is a probability conditioned to successful transmission in breeding areas and the probabilities of an infected bird migrating and shedding the virus as far as southern Brazil. The probability of wild species becoming exposed to H5N1-infected birds is high as they nest with northern migrants from Alaska, whereas for backyard poultry it is moderate to high depending on proximity to wetlands and the presence of species that could increase the likelihood of contact with wild birds such as domestic duck. The magnitude of the biological and economic consequences of successful transmission to poultry or wild birds would be low to severe depending on the probability of the occurrence of outbreak scenarios described. As a result, the risk estimate is greater than negligible, and HPAI H5N1 prevention strategy in the region should always be carefully considered by the veterinary services in Brazil.

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A data set of a commercial Nellore beef cattle selection program was used to compare breeding models that assumed or not markers effects to estimate the breeding values, when a reduced number of animals have phenotypic, genotypic and pedigree information available. This herd complete data set was composed of 83,404 animals measured for weaning weight (WW), post-weaning gain (PWG), scrotal circumference (SC) and muscle score (MS), corresponding to 116,652 animals in the relationship matrix. Single trait analyses were performed by MTDFREML software to estimate fixed and random effects solutions using this complete data. The additive effects estimated were assumed as the reference breeding values for those animals. The individual observed phenotype of each trait was adjusted for fixed and random effects solutions, except for direct additive effects. The adjusted phenotype composed of the additive and residual parts of observed phenotype was used as dependent variable for models' comparison. Among all measured animals of this herd, only 3160 animals were genotyped for 106 SNP markers. Three models were compared in terms of changes on animals' rank, global fit and predictive ability. Model 1 included only polygenic effects, model 2 included only markers effects and model 3 included both polygenic and markers effects. Bayesian inference via Markov chain Monte Carlo methods performed by TM software was used to analyze the data for model comparison. Two different priors were adopted for markers effects in models 2 and 3, the first prior assumed was a uniform distribution (U) and, as a second prior, was assumed that markers effects were distributed as normal (N). Higher rank correlation coefficients were observed for models 3_U and 3_N, indicating a greater similarity of these models animals' rank and the rank based on the reference breeding values. Model 3_N presented a better global fit, as demonstrated by its low DIC. The best models in terms of predictive ability were models 1 and 3_N. Differences due prior assumed to markers effects in models 2 and 3 could be attributed to the better ability of normal prior in handle with collinear effects. The models 2_U and 2_N presented the worst performance, indicating that this small set of markers should not be used to genetically evaluate animals with no data, since its predictive ability is restricted. In conclusion, model 3_N presented a slight superiority when a reduce number of animals have phenotypic, genotypic and pedigree information. It could be attributed to the variation retained by markers and polygenic effects assumed together and the normal prior assumed to markers effects, that deals better with the collinearity between markers. (C) 2012 Elsevier B.V. All rights reserved.

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Albatrosses and petrels (Procellariiformes) are migratory oceanic birds of considerable conservational interest. Polychlorinated biphenyls (PCBs) and organochlorine pesticides (OCPs) were assessed in the subcutaneous fat, liver and muscle of 100 birds belonging to eight species of Procellariiformes collected during their migration period in southern Brazil, one of the most important feeding areas for these species. Although the profiles of PCBs and OCPs were similar among the individuals, with predominance of penta, hexa and heptachlorobiphenyls and p'p-DDE, organochlorine concentrations exhibited a high degree of intra-species variability. The influence of body condition during the migration period in the distribution of organochlorine contaminants was also evaluated, showing that it is a significant factor in the variation and redistribution of these compounds in the tissues of these birds. The intense use of lipid reserves associated to the contamination from organochlorine compounds could be a troubling factor for seabirds with extended breeding periods and that spend most of their lives at sea migrating long distances, such as most of Procellariiformes. Studies on contamination are necessary to improve the knowledge of the threats to these birds and their populations as well as to contribute with information about persistent organic pollutants in the South Atlantic marine environment.

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The purpose of this article is to show how quantitative genetics has contributed to the huge genetic progress obtained in plant breeding in Brazil in the last forty years. The information obtained through quantitative genetics has given Brazilian breeders the possibility of responding to innumerable questions in their work in a much more informative way, such as the use or not of hybrid cultivars, which segregating population to use, which breeding method to employ, alternatives for improving the efficiency of selection programs, and how to handle the data of progeny and/or cultivars evaluations to identify the most stable ones and thus improve recommendations.

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Amazonian birds were caught and examined for the presence of ectoparasites in the Allpahuayo Mishana National Reserve near Iquitos, Peru, from 13 to 16 August 2011. A total of 40 birds representing 16 species were examined. Two birds (5%) were infested with 2 larvae of Amblyomma varium Koch, 1844, and one nymph of A. calcaratum Neumann, 1899. The 2 larvae of A. varium were infected with Rickettsia bellii. This is the first report of R. bellii in A. varium and also the first record of this rickettsia in Peru. In addition, an immature A. calcaratum is reported from Peru for the first time. (c) 2012 Elsevier GmbH. All rights reserved.

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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.

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The aim of the study was to evaluate rickettsial infection in ticks from wild birds of the Semidecidual and Atlantic Rainforest remnants of three municipalities of the State of Parana, southern Brazil. Overall, 53 larvae and nymphs collected from birds were checked for the presence of Rickettsia DNA by molecular tests. Five tick species were tested: Amblyomma aureolatum (Pallas), Amblyomma calcaratum Neumann, Amblyomma longirostre (Koch), Amblyomma ovale Koch, and Amblyomma parkeri Fonseca and Aragao. A. longirostre ticks were infected with the spotted fever group agents Rickettsia amblyommii strain AL (32.3% infection rate) and Rickettsia parkeri strain NOD (5.9% infection rate). A new rickettsial genotype was detected in the tick A. parkeri (50% infection rate), which had never been reported to be infected by rickettsiae. Through phylogenetic analysis, this new genotype, here designated as strain ApPR, grouped in a cluster composed by different strains of Rickettsia africae, Rickettsia sibirica, and R. parkeri. We consider strain ApPR to be a new genotype of R. parkeri. This study reports for the first time rickettsial infection in ticks from birds in southern Brazil. The role of migrating birds in the dispersal of these rickettsial strains should be considered in ecological studies of spotted fever group agents in Brazil.

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The pressures for land use change have led to an increasing isolation of habitat remnants throughout the world. The goal of this study was to estimate the population size and density of some endemic and threatened species in a nature reserve in the Cerrado biome. One hundred and thirty four point transects were undertaken at the Estacao Ecologica de Itirapina (EEI), one of the last natural grassland savannah remnants in Sao Paulo state, in the south-east of Brazil between September and December 2006 and densities estimated for seven species (four endemic to the Cerrado, one near-endemic and two grassland specialists). Neither species reached the minimum viable population size of 500-5000 individuals. Four species, White-banded Tanager, White-rumped Tanager, Black-throated Saltator and Sharp-tailed Tyrant have populations ranging from 112 to 248 individuals, while the other species have a low population (< 60 individuals). The mean densities of Sharp-tailed Tyrant and Cock-tailed Tyrant in the EEI grassland showed similar values to those observed in larger areas of the Cerrado, which may indicate that the EEL grassland area is well conserved. In spite of the restricted size of the EEI, small areas can maintain some endemic and threatened bird populations, thus contributing to local biodiversity and the ecological processes in the region. The capacity of fragments of Cerrado (similar to 2,000 ha) to maintain populations of endemic and threatened bird species is unlikely to be effective in the long term.

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This paper describes an outbreak of chytridiomycosis affecting a group of Dendrobates tinctorius, a Neotropical anuran species, confiscated from the illegal wildlife trade and housed in a private zoo in Brazil as part of an ex situ breeding program. We examined histological sections of the skin of 30 D. tinctorius and 20 Adelphobates galactonotus individuals. Twenty D. tinctorius (66.7%) and none of the A. galactonotus were positive for Batrachochytrium dendrobatidis (Bd). Multiple development stages of Bd infection were observed. The reasons for the interspecific difference in the rate of infection could not be determined, and further studies are advised. Because the examined population consisted of confiscated frogs, detailed epidemiological aspects could not be investigated, and the source of the fungus remains uncertain. The existence of ex situ amphibian populations is important for protecting species at higher risk in the wild, and ex situ amphibian conservation and breeding programs in Brazil may be established using confiscated frogs as founders. However, this paper alerts these programs to the urgency of strict quarantine procedures to prevent the introduction of potential pathogens, particularly Bd, into ex situ conservation programs.

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Birds that remove ectoparasites and other food material from their hosts are iconic illustrations of mutualistic-commensalistic cleaning associations. To assess the complex pattern of food resource use embedded in cleaning interactions of an assemblage of birds and their herbivorous mammal hosts in open habitats in Brazil, we used a network approach that characterized their patterns of association. Cleaning interactions showed a distinctly nested pattern, related to the number of interactions of cleaners and hosts and to the range of food types that each host species provided. Hosts that provided a wide range of food types (flies, ticks, tissue and blood, and organic debris) were attended by more species of cleaners and formed the core of the web. On the other hand, core cleaner species did not exploit the full range of available food resources, but used a variety of host species to exploit these resources instead. The structure that we found indicates that cleaners rely on cleaning interactions to obtain food types that would not be available otherwise (e.g., blood-engorged ticks or horseflies, wounded tissue). Additionally, a nested organization for the cleaner bird mammalian herbivore association means that both generalist and selective species take part in the interactions and that partners of selective species form an ordered subset of the partners of generalist species. The availability of predictable protein-rich food sources for birds provided by cleaning interactions may lead to an evolutionary pathway favoring their increased use by birds that forage opportunistically. Received 30 June 2011, accepted 10 November 2011.

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Surveys were conducted in Brazil, Benin and Tanzania to collect predatory mites as candidates for control of the coconut mite Aceria guerreronis Keifer, a serious pest of coconut fruits. At all locations surveyed, one of the most dominant predators on infested coconut fruits was identified as Neoseiulus baraki Athias-Henriot, based on morphological similarity with regard to taxonomically relevant characters. However, scrutiny of our own and published descriptions suggests that consistent morphological differences may exist between the Benin population and those from the other geographic origins. In this study, we combined three methods to assess whether these populations belong to one species or a few distinct, yet closely related species. First, multivariate analysis of 32 morphological characters showed that the Benin population differed from the other three populations. Second, DNA sequence analysis based on the mitochondrial cytochrome oxidase subunit I (COI) showed the same difference between these populations. Third, cross-breeding between populations was unsuccessful in all combinations. These data provide evidence for the existence of cryptic species. Subsequent morphological research showed that the Benin population can be distinguished from the others by a new character (not included in the multivariate analysis), viz. the number of teeth on the fixed digit of the female chelicera.

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Rodrigues M.N., Oliveira G.B., Silva R.S.S, Tivane C.T., Albuquerque J.F.G., Miglino M.A. & Oliveira M.F. 2012. [Gross morphology and topography of the digestive apparatus in rheas (Rhea americana americana).] Macroscopia e topografia do aparelho digestorio de emas (Rhea americana americana). Pesquisa Veterinaria Brasileira 32(7):681-686. Departamento de Cirurgia, Faculdade de Medicina Veterinaria e Zootecnia, Universidade de Sao Paulo, Cidade Universitaria, Av. Prof. Dr. Orlando Marques de Paiva 87, Sao Paulo, SP 05508270, Brazil. E-mail: marcio_medvet@hotmail.com Rheas are birds belonging to the ratites group and, among ostriches and emus, are the largest birds currently alive. In this work we studied the macroscopic aspects of rheas' digestive tract in order to provide important information to a better understanding of these birds' eating habits as well their anatomy. Twenty young animals aging between two and six months from the Centre for Wild Animals Multiplication (Cemas, scientific breeding license form Ibama no.1478912) were used. After dissection it was observed that their tongue was small and presented a rhomboid form, being disposed on the oral cavity floor, and inserted in its base by a frenulum. The esophagus was a rectilinear tube with elastic aspect and longitudinal elastic fibers, without dilation, which gives it an absence of crop. The proventriculus presented a fusiform form and the gastric ventricle showed and slightly oval form when filled, and was internally coated with a thick gastric cuticle. The small intestine was composed of three distinct regions: duodenum, jejunum and ileum. The duodenum had a light gray color and showed a "U" curved shaped. The jejunum was dark green, long and composed of several short loops arranged above each other. The ileum had a gray color and was connected with the jejunum. In ventral line to the rectum and cloaca, the ileum extended cranially, dorsally to the ascending duodenum. The large intestine was composed of two caeca, one right and one left, and colon-rectum and ileum were continuous with the cloaca. The structures of the rhea digestive tract resemble those described in the literature regarding to its shape and topography, even though rhea's caeca are well developed and relatively long.

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In addition to the strong influence of the broodstock diet on the development and survival of offspring, domestication may also interfere with the larval life success. We obtained eggs from wild and domesticated Salminus hilarii females and domesticated males. Wild females were caught in the Tiete River and tributaries, and the domesticated females were born three years before the beginning of the experiment in the Ponte Nova Fish Farm. Animals from both groups were fed with the same feed to exclude feed variables. The eggs and larvae were sampled at 0, 8, 16, and 28 h after spawning (HAS), with the last sampling (28 HAS) coinciding with hatching time. After hatching, samplings proceeded at 32, 48, 66, and 96 HAS, with the last sampling (96 HAS) corresponding to the end of yolk sac consumption. Finally, the last experimental period was during the larvae exogenous feeding phase, at 102, 118, 166, and 214 HAS. Our data revealed that domestication of S. hilarii females influenced fatty acid (FA) metabolism during embryo and larva development. However, the structure of membrane phospholipid FA remained mostly stable, with changes principally in the neutral fraction. When the external conditions, mainly water and feed quality, remained constant, domestication of S. hilarii females did not significantly affect the structural FA composition but influenced the selectivity of consumption and/or storage of specific FA.

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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.