62 research outputs found
Trophic niche partitioning of five skate species of genus Bathyraja in northern and central Patagonia, Argentina
Overexploitation of marine communities can lead to modifications in the structure of the food web and can force organisms like elasmobranchs to change their feeding habits. To evaluate the impact that fisheries have on food webs and on the interactions between species, it is necessary to describe and quantify the diet of the species involved and follow it through time. This study compares the diet of five skate species using the data obtained from the by-catch of the Argentine hake (Merluccius hubbsi) fishery in north and central Patagonia, Argentina. Diet composition was assessed by analysing the digestive tract contents and trophic overlapping between species of the genus Bathyraja: Bathyraja albomaculata, Bathyraja brachyurops, Bathyraja macloviana, Bathyraja magellanica and Bathyraja multispinis. A total of 184 stomachs were analysed. The diets of B. albomaculata and B. macloviana mainly comprised annelids, whereas that of B. brachyurops primarily comprised fish, including hake heads discarded by the fishery. The diets of B. magellanica and B. multispinis were largely based on crustaceans. Despite the morphological similarities and their shared preference for benthic habitats, no complete diet overlaps were found between the different species. These results suggest that these skate species have undergone a process of diet specialisation. This is a common feeding strategy that occurs to successfully eliminate competition when resources are limited, which corresponds to the conditions found in an environment being affected by the pressures of overfishing.Fil: Tschopp, Ayelen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Cristiani, Franco. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Puerto Madryn. Departamento de Biología y Ambiente; ArgentinaFil: Garcia, Nestor Anibal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; ArgentinaFil: Crespo, Enrique Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Puerto Madryn. Departamento de Biología y Ambiente; ArgentinaFil: Coscarella, Mariano Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Centro Nacional Patagónico. Centro para el Estudio de Sistemas Marinos; Argentina. Universidad Nacional de la Patagonia "San Juan Bosco". Facultad de Ciencias Naturales y Ciencias de la Salud - Sede Puerto Madryn. Departamento de Biología y Ambiente; Argentin
Spatial Models of Abundance and Habitat Preferences of Commerson’s and Peale’s Dolphin in Southern Patagonian Waters
Funding: This research was possible with the support of the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET). Funding for travel to and accommodation for NAD in Aberdeen, Scotland was provided by CONICET and Cetacean Society International. The work of NAD was part of a postdoctoral fellowship funded by CONICET. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Peer reviewedPublisher PD
Investigation of a mass stranding of 68 short-beaked common dolphins in Golfo Nuevo, Península Valdés, Argentina
We report on the investigation of a mass stranding of 68 short-beaked common dolphins (Delphinus delphis) that occurred in Golfo Nuevo, Península Valdés, Argentina in March 2018. Twenty-one of the stranded dolphins were returned alive to the sea, while 47 animals died. Dead dolphins included all ages, with more males than females (29 males and 18 females). The cause of death investigation reported here is restricted to 15 adult individuals and one fetus on which a full set of diagnostics was prioritized due to limited funding. Our results demonstrate that the death of 16 dolphins assessed in this study was not due to obvious human effects
(e.g. bycatch) or underlying pathologies, as all animals were in good body condition and had no external evidence of injuries. Infections by Morbillivirus, Influenza A virus, Sarcocystis spp., Toxoplasma gondii, or Neospora caninum, as well domoic acid (DA) toxicity were ruled out as ethiologies in this event. Notably, results on exposure to paralytic shelfish toxins (PSP) were the only investigated cause of death found positive. This is the first documentation of exposure to PSP toxins in short-beaked common dolphins from the Argentine Sea. At present our results are insufficient to assess whether PSP toxin exposure played a role in the death of the stranded dolphins. Notwithstanding, the full documentation and investigation of the most commonly reported pathogens and toxins involved in cetacean mass strandings allowed us to clear the most relevant health differentials and suggests areas for future study. Additional potential hypothesis related to factors known or speculated to cause cetacean mass strandings are currently being explored within the ecological context at the time of the event
Salute della donna in campo riproduttivo
Descrizione del concetto di salute di genere ed in campo riproduttivo- Epidemiologi
[A computerized multivariate analysis in the assessment of the prognosis of breast cancer after surgical excision]
The prognostic parameters most universally accepted as indicative for the assessment of 5 and 10 year survival in breast cancer are considered
FOOD EDUCATION: AN ISTRUMENT FOR CONSUMER’S HEALTH PROTECTION
Health is defined by WHO, as a “state of complete physical, mental and social well-being, not just absence of disease.” So it needs not simply treat but also prevent, inform, and promote healthy behaviors. From here the importance of putting into practice all possible strategies for prevention from age lowest. The purpose of this work is just to describe the project “Food and Culture”, between the IZSLT and and the Municipality of Ariccia in order to promote nutrition education in the family from the boys
Consumption of marine mammals by broadnose sevengill shark Notorynchus cepedianus in the northern and central Patagonian shelf
The study of food habits of the broadnose sevengill shark (Notorynchus cepedianus) based on the observation of the stomach contents of 22 individuals, revealed the importance of marine mammals as part of the shark's diet. The analysis showed that marine mammals represent at least 30% of the total consumed biomass by broadnose sevengill sharks. The frequency of occurrence was estimated to be 35%. The three pinnipeds with local distribution and at least two species of cetaceans were consumed. Although consumption of marine mammal was high, there was no evidence of direct attack on living preys by N. cepedianus, in Argentine waters
[A computerized multivariate analysis in the assessment of the prognosis of breast cancer after surgical excision]
The prognostic parameters most universally accepted as indicative for the assessment of 5 and 10 year survival in breast cancer are considered
- …