Estudo da presença de Mycobacterium avium subespécie paratuberculosis numa exploração leiteira no Litoral Centro de Portugal Continental

A Paratuberculose, conhecida também como Doença de Johne, é uma afeção infecciosa que provoca uma enterite granulomatosa crónica causada pelo agente Mycobacterium avium subespécie paratuberculosis (Map). É uma doença de carácter contagioso, de distribuição mundial, atingindo os mamíferos, particularmente os pequenos e grandes ruminantes, equinos, suínos, búfalos, coelhos, etc. Tem um grande impacto económico, nomeadamente na redução da produção leiteira, na redução dos teores de proteína no leite, na susceptibilidade a outras doenças, no refugo de animais e no aumento dos custos na sanidade. Pensa-se que também terá impacto a nível de Saúde Pública uma vez que o Map pode estar associado á doença de Crohn em humanos em que o leite cru, leite em pó ou leite pasteurizado podem ser os veículos de transmissão, porém não existem estudos suficientes para sustentar este acontecimento. A técnica de diagnóstico “Gold Standard” é a cultura microbiológica de fezes, no entanto é um procedimento muito demorado podendo levar até 4 meses para se observarem as colónias bacterianas, uma vez que o seu crescimento é muito lento. Deste modo, existem outros testes, tais como o PCR e ELISA, com elevada especificidade para o agente que fornecem resultados mais rápidos e que permitem minimizar os falsos-positivos, apesar da sua reduzida sensibilidade (por volta dos 50%). Este estudo é baseado na observação das instalações da exploração e consequente comparação com parâmetros analisados e documentados em literatura. Para além disso, são utilizadas informações fornecidas pelo Software da exploração com o intuito de estudar a incidência da Paratuberculose, ao longo dos anos, de modo a comprovar se as medidas de maneio e de higiene adotadas pela exploração afetada contribuem ou não de alguma maneira para o controlo/erradicaçãoda doença de Johne.

Studies on the anatomy and physiology of the tongue

This paper contains a review of the human tongue as well as fish, amphibians, birds, and mammals, and includes numerous illustrations.

Jorge Carrera Andrade, poeta del hombre (Estudios)

El autor lee a Carrera Andrade como un creador surgido en el quiebre de los presupuestos, ideologías y esperanzas del siglo XIX e inicios del XX, más plagado de incertidumbres que de certezas. Acaso el rasgo autobiográfico de su poesía, y su apego a una temática múltiple –no apartada nunca del desciframiento de los sentidos de lo pequeño– han oscurecido la intención del autor de reflexionar sobre la condición y el destino del hombre moderno. Cercano al existencialismo, en tanto filosofía develadora de la fragilidad y soledad humanas, de la futilidad de sus construcciones intelectuales, Carrera fue testigo –en un siglo de confrontaciones– «de la fealdad triunfante y la libertad encadenada». El poeta describe tres atributos definitorios del hombre moderno: soledad, imposibilidad de ser libre, y su condición de desterrado. Plantea Carrera que estas condiciones ontológicas de soledad y de ser prisionero no se agotarían en el hombre, sino que conformarían también a otros seres y objetos del universo. El destierro aludiría no solo a la condición literal del exiliado, sino también a la ausencia de un hogar espiritual, aunque, en relación a este punto, parece arribar a una cierta conciliación mediante la idea de que es posible trascender la finitud del individuo en la pervivencia de la humanidad entera –destino común el del «hombre planetario», cantado por el poeta a pesar de su soledad y sus prisiones.

Evidence Suggesting that Ivory-billed Woodpeckers (Campephilus principalis) Exist in Florida

The Ivory-billed Woodpecker (Campephilus principalis) disappeared from the forests of southeastern North America in the early 20th Century and for more than 50 years has been widely considered extinct. On 21 May 2005, we detected a bird that we identified as an Ivory-billed Woodpecker in the mature swamp forest along the Choctawhatchee River in the panhandle of Florida. During a subsequent year of research, members of our small search team observed birds that we identified as Ivory-billed Woodpeckers on 14 occasions. We heard sounds that matched descriptions of Ivory-billed Woodpecker acoustic signals on 41 occasions. We recorded 99 putative double knocks and 210 putative kent calls. We located cavities in the size range reported for Ivory-billed Woodpeckers and larger than those of Pileated Woodpeckers (Dryocopus pileatus) that have been reported in the literature or that we measured in Alabama. We documented unique foraging signs consistent with the feeding behavior of Ivory-billed Woodpeckers. Our evidence suggests that Ivory-billed Woodpeckers may be present in the forests along the Choctawhatchee River and warrants an expanded search of this bottomland forest habitat.

Evaluating the Small Population Paradigm for Rare Large-Bodied Woodpeckers, with Implications for the Ivory-billed Woodpecker

Six large-bodied, ≥ 120 g, woodpecker species are listed as near-threatened to critically endangered by the International Union for Conservation of Nature (IUCN). The small population paradigm assumes that these populations are likely to become extinct without an increase in numbers, but the combined influences of initial population size and demographic rates, i.e., annual adult survival and fecundity, may drive population persistence for these species. We applied a stochastic, stage-based single-population model to available demographic rates for Dryocopus and Campephilus woodpeckers. In particular, we determined the change in predicted extinction rate, i.e., proportion of simulated populations that went extinct within 100 yr, to concomitant changes in six input parameters. To our knowledge, this is the first study to evaluate the combined importance of initial population size and demographic rates for the persistence of large-bodied woodpeckers. Under a worse-case scenario, the median time to extinction was 7 yr (range: 1–32). Across the combinations of other input values, increasing initial population size by one female induced, on average, 0.4%–3.2% (range: 0%–28%) reduction in extinction rate. Increasing initial population size from 5–30 resulted in extinction rates < 0.05 under limited conditions: (1) all input values were intermediate, or (2) Allee effect present and annual adult survival ≥ 0.8. Based on our model, these species can persist as rare, as few as five females, and thus difficult-to-detect, populations provided they maintain ≥ 1.1 recruited females annually per adult female and an annual adult survival rate ≥ 0.8. Athough a demographic-based population viability analysis (PVA) is useful to predict how extinction rate changes across scenarios for life-history attributes, the next step for modeling these populations should incorporate more easily acquired data on changes in patch occupancy to make predictions about patch colonization and extinction rates.

Nonbreeding-Season Drivers of Population Dynamics in Seasonal Migrants: Conservation Parallels Across Taxa

For seasonal migrants, logistical constraints have often limited conservation efforts to improving survival and reproduction during the breeding season only. Yet, mounting empirical evidence suggests that events occurring throughout the migratory life cycle can critically alter the demography of many migrant species. Herein, we build upon recent syntheses of avian migration research to review the role of non-breeding seasons in determining the population dynamics and fitness of diverse migratory taxa, including salmonid fishes, marine mammals, ungulates, sea turtles, butterflies, and numerous bird groups. We discuss several similarities across these varied migrants: (i) non-breeding survivorship tends to be a strong driver of population growth; (ii) non-breeding events can affect fitness in subsequent seasons through seasonal interactions at individual- and population-levels; (iii) broad-scale climatic influences often alter non-breeding resources and migration timing, and may amplify population impacts through covariation among seasonal vital rates; and (iv) changes to both stationary and migratory non-breeding habitats can have important consequences for abundance and population trends. Finally, we draw on these patterns to recommend that future conservation research for seasonal migrants will benefit from: (1) more explicit recognition of the important parallels among taxonomically diverse migratory animals; (2) an expanded research perspective focused on quantification of all seasonal vital rates and their interactions; and (3) the development of detailed population projection models that account for complexity and uncertainty in migrant population dynamics.

Senescence rates are determined by ranking on the fast-slow life-history continuum

Comparative analyses of survival senescence by using life tables have identified generalizations including the observation that mammals senesce faster than similar-sized birds. These generalizations have been challenged because of limitations of life-table approaches and the growing appreciation that senescence is more than an increasing probability of death. Without using life tables, we examine senescence rates in annual individual fitness using 20 individual-based data sets of terrestrial vertebrates with contrasting life histories and body size. We find that senescence is widespread in the wild and equally likely to occur in survival and reproduction. Additionally, mammals senesce faster than birds because they have a faster life history for a given body size. By allowing us to disentangle the effects of two major fitness components our methods allow an assessment of the robustness of the prevalent life-table approach. Focusing on one aspect of life history - survival or recruitment - can provide reliable information on overall senescence.