99 resultados para Columba
Resumo:
The aim of this study was to evaluate a simple molecular method of reverse transcriptase polymerase chain reaction (RT-PCR) to differentiate Newcastle disease virus strains according to their pathogenicity, in order to use it in molecular screening of Newcastle disease virus in poultry and free-living bird populations. Specific primers were developed to differentiate LaSota-LS-(vaccine strain) and Sao Joao do Meriti-SJM-strain (highly pathogenic strain). Chickens and pigeons were experimentally vaccinated/infected for an in vivo study to determine virus shedding in feces. Validation of sensitivity and specificity of the primers (SJM and LS) by experimental models used in the present study and results obtained in the molecular analysis of the primers by BLAST made it possible to generalize results. The development of primers that differentiate the level of pathogenicity of NDV stains is very important, mainly in countries where real-time RT-PCR is still not used as a routine test. These primers were able to determine the presence of the agent and to differentiate it according to its pathogenicity. © 2012 Springer Science+Business Media B.V.
Resumo:
Pós-graduação em Microbiologia - IBILCE
Resumo:
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Resumo:
Karyotypes are compared of 14 species of Brazilian Columbiformes (family Columbidae): Claravis pretiosa (2n=74), Columba cayennensis (2n=76), Columba picazuro (2n=76), Columba speciosa (2n=76), Columbina minuta (2n=76), Columbina passerina (2n=76), Columbina picui (2n=76), Columbina talpacoti (2n=76), Geotrygon montana (2n=86), Leptotila rufaxilla (2n=76), Leptotila verreauxi (2n=78), Scardafella squammata (2n=78), Uropelia campestris (2n=68) and Zenaida auriculata (2n=76). The macrochromosomes of each species were analysed by conventional Giemsa staining, cytobiometrically and with G-and C-banding. All species studied are characterized by typical bird karyotypes with a few pairs of macrochromosomes and many microchromosomes. The morphology and relative length of the Z chromosome are nearly the same in all species, but the W chromosome shows variation. The G-band patterns of the first pair in Columbiformes show a large positive band distally in the long arm, common to all species of the order. The constitutive heterochromatin is restricted to the centromeres of the macro- and microchromosomes. The W is the most heterochromatic chromosome in all species studied. Studies of relative lengths, arm ratios and G- and C-banding patterns showed that in Columbiformes pairs 3, 4 and 5 are the most stable. The types of rearrangements distinguishing between species vary among the genera: pericentric inversions in Columba; fusions and translocations in Uropelia; centric fissions in Geotrygon; fusions, translocations, para and pericentric inversions in Columbina, Leptotila, Zenaida and Scardafella. On the basis of the karyological findings the phylogenetic relationships of the Brazilian Columbiformes are discussed. © 1984 Dr W. Junk Publishers.
Resumo:
Scopo del lavoro della presente tesi è stato quello di valutare la prevalenza di Chlamydiaceae, ed in particolare Chlamydia psittaci, in una popolazione aviare con caratteristiche sinantropiche quale il colombo di città (Columba livia var. domestica) dell’areale veneziano. Per evidenziare il patogeno sono state utilizzate metodiche sierologiche, d’isolamento e biomolecolari tradizionali. Contestualmente, mediante tecnologie molecolari innovative, quali microarray ed MLVA (Multilocus VNTR Assay) sono stati valutati i genotipi di C. psittaci e le eventuali altre specie di Chlamydia presenti in tale popolazione. Inoltre, si è proceduto ad una classificazione delle lesioni anatomo-patologiche ed ad una loro correlazione con la presenza del patogeno. I risultati dimostrano che la prevalenza di C. psittaci nella popolazione oggetto dello studio è del 10%. Durante tale studio è stata dimostrata la presenza di un ceppo di C. psittaci atipico, in quanto non classificabile con le attuali tecniche a disposizione. La genotipizzazione dei ceppi di C. psittaci conferma la presenza nel colombo di città del genotipo B, E ed E/B, che solitamente risultano essere coinvolti con minore frequenza in episodi di infezione umana. Inoltre sono stati dimostrati alcuni ceppi classificati come Chlamydia spp., in quanto le metodologie applicate e le conoscenze attuali non permettono ulteriori distinzioni, prospettando la possibilità di un nuovo ceppo. Infine, attraverso l’analisi dei dati raccolti durante la prima fase di campionamenti e successivamente confermati durante la seconda fase, siamo riusciti a strutturare un sistema di selezione, basato su caratteristiche funzionali ed anatomopatologiche, che permette di selezionare in sede necroscopica i colombi molto probabilmente infetti, permettendo conseguentemente una migliore organizzazione e gestione dei campioni di interesse contenendo nel contempo i costi ma mantenendo elevati gli standards diagnostici.
Resumo:
Three rhesus monkeys (Macaca mulatta) and four pigeons (Columba livia) were trained in a visual serial probe recognition (SPR) task. A list of visual stimuli (slides) was presented sequentially to the subjects. Following the list and after a delay interval, a probe stimulus was presented that could be either from the list (Same) or not from the list (Different). The monkeys readily acquired a variable list length SPR task, while pigeons showed acquisition only under constant list length condition. However, monkeys memorized the responses to the probes (absolute strategy) when overtrained with the same lists and probes, while pigeons compared the probe to the list in memory (relational strategy). Performance of the pigeon on 4-items constant list length was disrupted when blocks of trials of different list lengths were imbedded between the 4-items blocks. Serial position curves for recognition at variable probe delays showed better relative performance on the last items of the list at short delays (0-0.5 seconds) and better relative performance on the initial items of the list at long delays (6-10 seconds for the pigeons and 20-30 seconds for the monkeys and a human adolescent). The serial position curves also showed reliable primacy and recency effects at intermediate probe delays. The monkeys showed evidence of using a relational strategy in the variable probe delay task. The results are the first demonstration of relational serial probe recognition performance in an avian and suggest similar underlying dynamic recognition memory mechanisms in primates and avians. ^
Resumo:
A primary objective of Leg 175 was to investigate the upwelling history of the Benguela Current. Upwelling along the coast is found over the shelf in several well-established cells, as well as along the shelf-slope break, and extends over the 1000-m isobath. Streaming filaments along the coast also carry upwelled water off shore (Shannon, 1985). The upwelled nutrient-rich waters are sourced from the South Atlantic central water mass, which is a mixture of subtropical and subantarctic water masses. Below the central water mass lies Antarctic intermediate water (Shannon and Hunter, 1988, doi:10.2989/025776188784480735; Stramma and Peterson, 1989, doi:10.1175/1520-0485(1989)019<1440:GTITBC>2.0.CO;2). The upwelling system supports a robust marine community (Shannon and Pillar, 1986) where radiolarians are abundant (Bishop et al., 1978, doi:10.1016/0146-6291(78)90010-3). The endemic nature of radiolarians makes them useful in reconstructing the paleocirculation patterns. The biogeographic distribution of many species is limited by water-mass distribution. In a given geographic region, species may also have discrete depth habitats. However, their depth of occurrence can change worldwide because the depths of water masses vary with latitude (Boltovskoy, 1999). Consequently, species found at shallow depths at high latitudes (cold-water fauna) are observed deeper in the water column at lower latitudes. The low-latitude submergence of cold-water species broadens their distribution, resulting in species distributions that can cover multiple geographic regions (Kling, 1976, doi:10.1016/0011-7471(76)90880-9; Casey, doi:10.1016/0031-0182(89)90017-5; 1971; Boltovskoy, 1987, doi:10.1016/0377-8398(87)90014-4). Since radiolarian distribution is closely related to water-mass distribution and controlled by climatic conditions rather than geographic regions, similar assemblages characterize the equatorial, subtropical, transition, subpolar, and polar regions of ocean basins (Petrushevskaya, 1971a; Casey, 1989, doi:10.1016/0031-0182(89)90017-5; Boltovskoy, 1999). Numerous radiolarian species found in water masses in the Angola and Benguela Current systems have also been observed in plankton net samples, sediment traps, and surface-sediment studies in the Atlantic sector of the Southern Ocean, where they exhibited particular water-mass affinities (Abelmann, 1992a, doi:10.1007/BF00243107; Abelmann 1992b, doi:10.1007/BF00243108; Abelmann and Gowing, 1997, doi:10.1016/S0377-8398(96)00021-7). This report presents data on the radiolarian fauna recovered from Site 1082 sediments in the form of a survey of species reflecting the latitudinal migration of the Angola-Benguela Front and upwelling. The data constitute a time series of relative radiolarian abundances at very high resolution (every 20 cm) of the upper 12 m of Hole 1082A.