990 resultados para breeding birds


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An outbreak of cryptococcosis occurred in a breeding aviary in São Paulo, Brazil. Seven psittacine birds (of species Charmosyna papou, Lorius lory, Trichoglossus goldiei, Psittacula krameri and Psittacus erithacus) died of disseminated cryptococcosis. Incoordination, progressive paralysis and difficulty in flying were seen in five birds, whereas superficial lesions coincident with respiratory alterations were seen in two birds. Encapsulated yeasts suggestive of Cryptococcus sp. were seen in faecal smears stained with India ink in two cases. Histological examination of the birds showed cryptococcal cells in various tissues, including the beak, choana, sinus, lungs, air sacs, heart, liver, spleen, kidneys, intestines and central nervous system. High titres of cryptococcal antigen were observed in the serum of an affected bird. In this case, titres increased during treatment and the bird eventually died. Yeasts were isolated from the nasal mass, faeces and liver of one bird. Cryptococcus neoformans var. gattii serovar B was identified based on biochemical, physiological and serological tests. These strains were resistant (minimum inhibitory concentration 64 μ g/ml) to fluconazole. This is the first report of C. neoformans var. gattii occurring in psittacine birds in Brazil. © 2004 ISHAM.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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Though intended as a field guide to the birds of the Great Plains, this book seems to serve best as a general introduction to Great Plains birds and will mostly benefit those casually interested in birds. The definition of Great Plains the book uses is rather broad, and some species are included that, in my opinion, aren't really birds of the Great Plains. For example, several warblers are included as breeding species although they nest within the book's definition of the region only in the conifer or mixed forest of north-central to northwestern Minnesota, which isn't really a part of the Great Plains proper.

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Due to rapid and continuous deforestation, recent bird surveys in the Atlantic Forest are following rapid assessment programs to accumulate significant amounts of data during short periods of time. During this study, two surveying methods were used to evaluate which technique rapidly accumulated most species (> 90% of the estimated empirical value) at lowland Atlantic Forests in the state of São Paulo, southeastern Brazil. Birds were counted during the 2008-2010 breeding seasons using 10-minute point counts and 10-species lists. Overall, point counting detected as many species as lists (79 vs. 83, respectively), and 88 points (14.7 h) detected 90% of the estimated species richness. Forty-one lists were insufficient to detect 90% of all species. However, lists accumulated species faster in a shorter time period, probably due to the nature of the point count method in which species detected while moving between points are not considered. Rapid assessment programs in these forests will rapidly detect more species using 10-species lists. Both methods shared 63% of all forest species, but this may be due to spatial and temporal mismatch between samplings of each method.

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The widespread use of artificial nestboxes has led to significant advances in our knowledge of the ecology, behaviour and physiology of cavity nesting birds, especially small passerines Nestboxes have made it easier to perform routine monitoring and experimental manipulation of eggs or nestlings, and also repeatedly to capture, identify and manipulate the parents However, when comparing results across study sites the use of nestboxes may also Introduce a potentially significant confounding variable in the form of differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained However, the use of nestboxes may also introduce an unconsidered and potentially significant confounding variable clue to differences in nestbox design amongst studies, such as their physical dimensions, placement height, and the way in which they are constructed and maintained Here we review to what extent the characteristics of artificial nestboxes (e g size, shape, construction material, colour) are documented in the 'methods' sections of publications involving hole-nesting passerine birds using natural or excavated cavities or artificial nestboxes for reproduction and roosting Despite explicit previous recommendations that authors describe in detail the characteristics of the nestboxes used, we found that the description of nestbox characteristics in most recent publications remains poor and insufficient We therefore list the types of descriptive data that should be included in the methods sections of relevant manuscripts and justify this by discussing how variation in nestbox characteristics can affect or confound conclusions from nestbox studies We also propose several recommendations to improve the reliability and usefulness of research based on long-term studies of any secondary hole-nesting species using artificial nestboxes for breeding or roosting.

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Corticosterone, the main stress hormone in birds, mediates resource allocation, allowing animals to adjust their physiology and behaviour to changes in the environment. Incubation is a time and energy-consuming phase of the avian reproductive cycle. It may be terminated prematurely, when the parents' energy stores are depleted or when environmental conditions are severe. In this study, the effects of experimentally elevated baseline corticosterone levels on the parental investment of incubating male Adelie penguins were investigated. Incubation duration and reproductive success of 60 penguins were recorded. The clutches of some birds were replaced by dummy eggs, which recorded egg temperatures and rotation rates, enabling a detailed investigation of incubation behaviour. Corticosterone levels of treated birds were 2.4-fold higher than those of controls 18 days post treatment. Exogenous corticosterone triggered nest desertion in 61% of the treated birds; consequently reducing reproductive success, indicating that corticosterone can reduce or disrupt parental investment. Regarding egg temperatures, hypothermic events became more frequent and more pronounced in treated birds, before these birds eventually abandoned their nest. The treatment also significantly decreased incubation temperatures by 1.3 °C and lengthened the incubation period by 2.1 days. However, the number of chicks at hatching was similar among successful nests, regardless of treatment. Weather conditions appeared to be particularly important in determining the extent to which corticosterone levels affected the behaviour of penguins, as treated penguins were more sensitive to severe weather conditions. This underlines the importance of considering the interactions of organisms with their environment in studies of animal behaviour and ecophysiology.

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The “El Hondo Nature Park” is mainly composed of a series of irrigation channels and water reservoirs, subjected to various regimes of management as well as reed and vegetation control, thus creating a great variety of habitats and situations. To determine the influence of these habitats and management regimes on the local bird community, a set of characteristics of these channels and their surrounding area were analysed with a Correspondence Analysis (CA). The degree of reed development in channels and the presence in the surroundings of orchards and other reed formations were the most decisive factors to explain the probability of occurrence of reed birds and waterbirds, as well as bird species richness and abundance. Other bird species were not directly influenced by channel variables, but only by those of surrounding land uses.

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Background: The importance that birds of the Columbidae family have had throughout history is visible on the Mediterranean coast. Pigeon fancying is the art of breeding and training carrier pigeons and currently, several breeds exist. The sport of racing pigeons consists in covering a distance at maximum possible speed. However, pigeon breeding has another modality called “sport pigeon”, where several males follow a female. This study focusses on ethnobotanical knowledge of native and exotic plant species that are used for diet, breeding, stimulation, healing illnesses and staining the plumage of pigeons bred in captivity. Methods: Using semi-structured interviews, we gathered information about the different plant species traditionally used for pigeon-breeding in the region of Valencia. Background material on remedies for bird illnesses was gathered from folk botanical references, local books and journals. The plant species were collected in the study area, then identified in the laboratory using dichotomous keys and vouchered in the ABH (Herbarium of Alicante University). We used Excel ® 2003 to perform a simple statistical analysis of the data collected. Results: We collected 56 species of plants (and one variety) that included 29 botanical families. The total number of species was made up of 35 cultivated and 21 wild plants. The most common were Gramineae (14 species), Leguminosae (6 species), and Compositae (4 species). Conclusions: Pigeon breeding is an immensely popular activity in Eastern Spain, and ethnobiological knowledge about breeding pigeons and caring for them is considerable. The names and traditional uses of plants depend on their geographical location, vernacular names serve as an intangible heritage. Feeding, environmental features, and genetic makeup of individuals are relevant aspects in the maintenance of avian health.

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Breeding individuals enter an emergency life-history stage when their body reserves reach a minimum threshold. Consequently, they redirect current activity toward survival, leading to egg abandonment in birds. Corticosterone (CORT) is known to promote this stage. How and to what extent CORT triggers egg abandonment when breeding is associated with prolonged fasting, however, requires further investigation. We manipulated free-living male Adelie penguins with CORT-pellets before their laying period. We then examined their behavioral response with respect to nest abandonment in parallel with their prolactin levels (regulating parental care), and the subsequent effects of treatment on breeding success in relieved birds. Exogenous CORT triggered nest abandonment in 60% of the treated penguins -14 days after treatment and induced a concomitant decline in prolactin levels. Interestingly, prolactin levels in treated penguins that did not abandon their nest were higher at the point of implantation and also after being relieved by females, when compared with abandoning penguins. Among successful birds, the treatment did not affect the number of chicks, nor the brood mass. Our results show the involvement of CORT in the decision-making process regarding egg abandonment in Adelie penguins when incubation is associated with a natural long fast. However, we suggest that CORT alone is not sufficient to trigger nest abandonment but that 1) prolactin levels need to reach a low threshold value, and 2) a rise in proteolysis (i.e. utilization of protein as main energy substrate) seems also to be required.

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Mode of access: Internet.

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Includes indexes

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"Separate from Yearbook of the Department of Agriculture, 1917. no. 723."