Hydrographic features and dynamics of blue whiting, mackerel and horse mackerel in the bay of biscay, 1994-1996. A multidisciplinary study on sefos

Hydrographic and climatic conditions have been found to be one of the most important factors that can influence the distnbution and behaviour of adults, juveniles and early stages of fish. This relationship, which has been pointed out by several authors, is also the main objective ofthe SEFOS project, which studies the relationship between the distnbutions and migrations of commercially important fish species and the oceanography of the European shelf edge. Within this framework, the Bay of Biscay presents special oceanographic and climatic conditions that could intluence the aggregations of food and larvae in retention areas throughout this zone, which is one of the most important nursery areas for several fish species and seasonal migrations of blue whiting, horse mackerel and mackerel This paper presents the results of a multidisciplinary study of the relationship between the oceanographic conditions ofthe Bay ofBiscay and the distribution ofboth early stages - eggs and larvae - and adult fish ofhorse mackerel, mackerel and blue whiting for the period 1994-1996

Recent changes in the pelagic ecosystem of the Iberian Atlantic in the context of multidecadal variability

Trends in ecosystem variables of the Eastern North Atlantic shelf near the Iberian Peninsula were analysed in relation to regional climate and oceanographic variability. In addition, detailed changes in oceanographic properties (surface temperature, upwelling and poleward current activity) and biological components (plankton and pelagic consumers) in the period 1989-2005 were compared with the main trends and multidecadal periods observed in time series dating back to 1950. In contrast to previous studies, the North Atlantic Oscillation did not appear as the main influence in the climate of the North Iberian region, while East-West and subtropical gradients were the dominant modes. Climatic oscillations at decadal scales were paralleled by similar oscillations in oceanographic and biological variables, but the latter appeared weakly related to climate. Time- lags of up to 5 years in the biological response may partly explain these relationships. The main planktivorous fish species (sardine and anchovy) alternate in periods of 10-15 years of relative dominance, in synchrony with equivalent species around the world. In contrast, plankton cycles appear greatly modified after 1990 in coincidence with shifts in climatic and oceanographic variables. Subregional variability indicated divergent trends in biological variables, particularly the zooplankton increase off A Coruña and the decrease in the Bay of Biscay since 1990. Such divergences are related to direct and indirect effects of global changes in this transitional upwelling region

Pythiosis in sheep from Paraná, southern Brazil

Abstract: This paper reports pythiosis in a sheep from southwestern Paraná, Brazil, confirmed by indirect ELISA (Enzime-Linked Immunosorbent Assay) and immunohistochemistry, as well as it describes the macro and microscopic injuries, in order to understand the pathogenicity. A 4-year-old ewe from a flock of 30 Santa Inês sheep, raised semi-extensively with access to a weir, showed cachexia, bilateral enlargement in nasal region, a serous and bloody secretion with a fetid odor from its nose and swollen submandibular and retropharyngeal lymph nodes. Blood collection was performed trough jugular vein puncture in order to make complete blood cell count (CBC) and to obtain serum for the subsequent serological examination. As the hematological counts were within the normal range for sheep, the animal was euthanized and submitted to necropsy. Indirect ELISA resulted positive for pythiosis. Necropsy revealed necrosis of the hard palate with a diameter of 3.5cm and extending up to the nasal cavity, forming a fistula. Submandibular and retropharyngeal lymph nodes were enlarged and edematous on section. Microscopic findings for submandibular and retropharyngeal lymph nodes consisted in moderate infiltration of eosinophils mainly in the subcapsular sinus, characterizing reactive eosinophilic lymphadenitis. The nasal cavity revealed rhinitis and oral cavity stomatitis with necro-eosinophilic and pronounced multifocal granulomatous infiltration and presence of hyphae. Hyphae found in palate and nasal cavity were positive for Pythium insidiosum by Grocott's method and immunohistochemistry, the last one considered to be confirmatory for the pathogen diagnostic. This report has an important epidemiological aspect, as it is the first case of pythiosis in sheep confirmed by serology in South Brazil and an alert of possible infection by the pathogen in floodplains

Pythium insidiosum: morphological and molecular identification of Brazilian isolates

Pythium insidiosum is an oomycete belonging to the kingdom Stramenipila and it is the etiologic agent of pythiosis. Pythiosis is a life-threatening infectious disease characterized by the development of chronic lesions on cutaneous and subcutaneous, intestinal, and bone tissues in humans and many species of animals. The identification of P. insidiosum is important in order to implement a rapid and definitive diagnosis and an effective treatment. This study reports the identification of 54 isolates of P. insidiosum of horses, dogs and sheep that presented suspicious clinical lesions of pythiosis from different regions in Brazil, by using morphological and molecular assays. Throughout the PCR it was possible to confirm the identity of all Brazilian isolates as being P. insidiosum