5,965 research outputs found
Seasonal variation in the diet of Lontra longicaudis in the Paraná River basin, Argentina
We studied the Neotropical otter ( Lontra longicaudis ) seasonal diet variations in the middle Paran á River valley, in central-northern Argentina, at the southern limit of its global range. We recorded 745 prey items in 320 scats collected over the course of 1 year in a tributary stream of the Paran á River. Fish, crustaceans, mammals, and insects were the most important items in frequency of occurrence among items. Other items, like mollusks, birds, amphibians, and reptilians were presented in low frequency in all seasons. We recorded seasonal variation in the frequency of the principal categories items: fish, mammals, crustaceans, and insects and in reptilian that had low frequency. Although fish were the most common items consumed by the otter, other groups such as crustaceans, mammals, and insects, were also important in the diet of the Neotropical otter throughout the seasons. Mammals and insects showed a higher frequency in the Neotropical otter diet in our study than in Brazil, Mexico, and even northern Argentina. We noted a marked variation throughout the Neotropical region in the niche breadth indices among studies of Neotropical otter ’ s diet. The Shannon H ′ diversity index showed a higher value in our study than in most of previous diet analyses of this species.Fil: Vezzosi, Raúl Ignacio. Provincia de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Universidad Autónoma de Entre Ríos. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Centro de Investigaciones Científicas y Transferencia de Tecnología a la Producción; ArgentinaFil: Eberhardt, María Ayelen Teresita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Ciencias Veterinarias del Litoral. Universidad Nacional del Litoral. Facultad de Cs.veterinarias. Instituto de Ciencias Veterinarias del Litoral; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina. Laboratorio de Ecología de Enfermedades; ArgentinaFil: Raimondi, Vanina Belén. Universidad Nacional de Rosario. Facultad de Ciencias exactas, Ingeniería y Agrimensura. Museo "Florentino y Carlos Ameghino"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Gutierrez, Marìa Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto Nacional de Limnología. Universidad Nacional del Litoral. Instituto Nacional de Limnología; ArgentinaFil: Pautasso, Andrés A.. Universidad Nacional de Rosario. Facultad de Ciencias exactas, Ingeniería y Agrimensura. Museo "Florentino y Carlos Ameghino"; Argentin
Occurrence of the Sinus Nematode Skrjabingylus sp. (Nematoda: Metastrongyloidea) Inferred from Sinus Lesions in Arkansas Mustelidae and Mephitidae, with review of relevant literature
Nasal nematodes of the genus Skrjabingylus occur in the mammalian families Mustelidae and Mephitidae, and have been found from Canada to Costa Rica. Ingestion of infected snails, frogs, snakes, or mice can lead to infection of these mammalian hosts. Infection often causes pathology to bones in the sinus region, which may lead to discoloration, enlargement, and fenestrations of the bone. Examination of museum specimens for bone lesions or other evidence of infection has been used to evidence prior infection, but prevalence and intensity cannot be interpreted without actually recovering the parasite. We examined Mustelids and Mephitids in collections of mammals housed at Arkansas State University (ASU), Henderson State University (HSU), and the University of Arkansas at Little Rock (UALR) to evaluate the possible occurrence of nasal nematodes in Arkansas mammals. Evidence of infection was found in skulls of the Striped Skunk (Mephitis mephitis), Spotted Skunk (Spilogale putorius), Mink (Neovison vison), Long-tailed Weasel (Mustela frenata), and North American River Otter (Lontra canadensis) from Arkansas. We report for the first time evidence of the presence and distribution of Skrjabingylus sp. infecting mammals in Arkansas
Insights on the role of forest cover and on the changes in forest cover on thirty-five endangered mammal species distributions
The changes in forest cover can determine the survival of terrestrial endangered mammal species in the wild. This study assessed the impacts of forest cover changes on endangered mammal species distribution at global scale aiming to understand how the changes in forest cover may have impacted the distributions of 35 endangered small and large-body terrestrial mammals. There were used forest data obtained from time-series analyses of Landsat images between 2000 and 2014, species occurrence records collected by observations between 2000 and 2015 of Global Biodiversity Information Facility and species range data of International Union for Nature Conservation (IUCN) of the year 2015, to test the ‘natural and resource conditions’ hypothesis. Hypothesis on ‘natural and resource conditions’ produced models with high prediction accuracy of above 70 percent for 88 percent of 35 species models. The changes in forest cover explained species occurrences in 10 percent of all species models. In average, 59 percent of species occurrence records overlapped with species range data. The 51 percent of all species had no occurrence records between 2000 and 2015. Species and forest data collection as well as transnational cooperation for conservation of species roaming in the wild in upland forested areas and in cross-border areas may be critical for endangered mammal species conservation
Reproductive Den Habitat Characterization of American Badgers (\u3cem\u3eTaxidea taxus\u3c/em\u3e) in Central California
The American badger (Taxidea taxus) is a species of special concern in California, and, as such, conservation measures are necessary. The goal of this study was to identify potential reproductive den habitat characteristics in order to more accurately predict critical reproductive habitat in central California grasslands. A paired study design was used to examine differences between reproductive and non-reproductive sites, and logistical regression was used to analyze the variables and produce two predictive models, one with biotic factors and one with abiotic factors. Badgers in central Californian grasslands appear to rely on both biotic and abiotic factors when selecting locations for reproductive den sites. Predictive biotic variables included amount of ground vegetation, presence of predators, presence of prey, and nearest shrub width. Predictive abiotic variables included distance to a drainage point and slopes at 10, 30, and 40 m from the den entrance. Integrating information from these models into conservation efforts will identify critical reproductive habitat and help form viable conservation strategies for the species
Evolutionary history and identification of conservation units in the giant otter, Pteronura brasiliensis.
The giant otter, Pteronura brasiliensis, occupies a range including the major drainage basins of South America, yet the degree of structure that exists within and among populations inhabiting these drainages is unknown. We sequenced portions of the mitochondrial DNA (mtDNA) cytochrome b (612 bp) and control region (383 bp) genes in order to determine patterns of genetic variation within the species. We found high levels of mtDNA haplotype diversity (h = 0.93 overall) and support for subdivision into four distinct groups of populations, representing important centers of genetic diversity and useful units for prioritizing conservation within the giant otter. We tested these results against the predictions of three hypotheses of Amazonian diversification (Pleistocene Refugia, Paleogeography, and Hydrogeology). While the phylogeographic pattern conformed to the predictions of the Refugia Hypothesis, molecular dating using a relaxed clock revealed the phylogroups diverged from one another between 1.69 and 0.84 Ma, ruling out the influence of Late Pleistocene glacial refugia. However, the role of Plio-Pleistocene climate change could not be rejected. While the molecular dating also makes the influence of geological arches according to the Paleogeography Hypothesis extremely unlikely, the recent Pliocene formation of the Fitzcarrald Arch and its effect of subsequently altering drainage pattern could not be rejected. The data presented here support the interactions of both climatic and hydrological changes resulting from geological activity in the Plio-Pleistocene, in shaping the phylogeographic structure of the giant otter
Diet of the neotropical otter Lontra longicaudis (Carnivora: Mustelidae) from the Santiago River basin, Mexico
The diet of the neotropical otter Lontra longicaudis is reported in the Santiago River, Nayarit - Jalisco, Mexico. A diet based on fish was found (percentage of occurrence 43.86%), with lower frequencies of insects (22.81%), reptiles (9.36%) and amphibians (8.77%), with the introduced fish Oreochromis aureus and Cyprinus carpio, the most consumed.Se reporta la dieta de la nutria neotropical Lontra longicaudis en el Río Santiago, Nayarit/Jalisco, México. Se encontró una dieta basada en peces (porcentaje de ocurrencia 43.86%), con frecuencias menores de insectos (22.81%), reptiles (9.36%) y anfibios (8.77%), siendo los peces introducidos Oreochromis aureus y Cyprinus carpio, las especies más consumidas
The southern river otter (Lontra provocax): Insights from the perspective of Andean Patagonian ethnozoology
Animals play a significant role in many cultures around the world. The southern river otter Lontra provocax (known locally as the “huillín”) is endemic to southern Argentina and Chile, and is currently in danger of extinction. Mapuche communities have always lived closely alongside their animal resources, generating unique bonds with them. The objective of this work is to obtain an overview of the importance given to this species in the literature of the region with regard to the nature-culture connection. A systematic bibliographical review was carried out using reference libraries and web browsers. From all the sources analysed, 110 were selected which held biocultural information. The main approach used was ecological; however, the ethnohistorical texts provided the richest information on the bond between this otter and humans. The Mapuche name “huillín” appears in all the publications analysed, showing its continuity over time. Of all the zootoponyms found, 87.5% were Chilean and 12.5% were Argentine. The Argentine case is found in Nahuel Huapi lake, and is worthy of note as its name could involve the huillín. The results of this work increase our knowledge of the biocultural heritage of our region, and enable us to reflect on the associated historical and political processes.Fil: Pozzi, Carla Martina. Ministerio de Ambiente y Desarrollo Sustentable. Administración de Parques Nacionales. Parque Nacional "Nahuel Huapi". Departamento Conservación y Educación Ambiental; ArgentinaFil: Ladio, Ana Haydee. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Patagonia Norte. Instituto de Investigaciones en Biodiversidad y Medioambiente. Universidad Nacional del Comahue. Centro Regional Universidad Bariloche. Instituto de Investigaciones en Biodiversidad y Medioambiente; Argentina. Ministerio de Ambiente y Desarrollo Sustentable. Administración de Parques Nacionales. Parque Nacional "Nahuel Huapi". Departamento Conservación y Educación Ambiental; Argentin
Lontra longicaudis de vida livre infectada por parvovirus canino e parasitada por Dioctophyma renale
This study describes a case of parvovirus infection in a river otter (Lontra longicaudis) assisted at the Wildlife Rehabilitation Center and Wildlife Screening Center, Federal University of Pelotas (UFPel), Rio Grande do Sul state, Brazil. Clinical signs included apathy, dark and fetid diarrhea, and crusted lesions on the palmar pads of the fore and hind limbs. The animal died after undergoing support treatment with antibiotics, anti-inflammatory, and fluid therapy. At necropsy, the intestines were reddened and edematous and the right kidney was diminished by one third of its normal size and covered with whitish, spongy material. A female Dioctophyma renale was found free in the abdominal cavity. Histologically, dilatation of the intestinal crypts and fusion and blunting of the intestinal villi were observed. In addition, moderate, multifocal lymphocytic enteritis with lymphoid depletion in Peyer’s patches and mesenteric lymph nodes were present. Immunohistochemistry with anti-canine parvovirus monoclonal antibody (anti-CPV) was strongly positive in the bone marrow cells and enterocytes of the intestinal crypts, confirming the diagnosis of parvovirus infection. The peritoneum on the right kidney was expanded with a cuboidal cell border, forming multiple papillary projections associated with eggs of D. renale and severe inflammatory infiltrate (giant cells, macrophages, lymphocytes, eosinophils, and plasma cells). Areas of necrosis and mineralization were also observed. Due to fragmentation and degradation of its natural habitat, the otter approached the urban area and was contaminated with the virus, which is hosted and disseminated by domestic animals. Infection with D. renale can be associated with the large population of parasitized domestic animals, which eliminate the helminth eggs through urine, contaminating the environment where the parasite intermediate and paratenic hosts co-inhabit. The diseases of these animals can be a decline factor of wild populations that inhabit the region and are an alert to spillover risk.O animal estava debilitado, apático, apresentava diarreia escura e fétida e lesões crostosas nos coxins palmares dos membros torácicos e pélvicos, morrendo após tratamento de suporte com antibiótico, anti-inflamatório e fluidoterapia. Na necropsia os intestinos estavam edematosos e avermelhados e o rim direito estava recoberto de material brancacento e esponjoso, com comprometimento de cerca de um terço do órgão. Foi observado, também, um exemplar de Dioctophyma renale, fêmea, livre na cavidade abdominal. Histologicamente havia fusionamento das vilosidades, dilatação das criptas intestinais com enterite linfocítica moderada multifocal e depleção linfoide nos linfonodos mesentéricos. Na técnica de imuno-histoquímica (IHQ) com anticorpo monoclonal anti-Parvovírus canino (Anti-CPV) houve marcação positiva nos enterócitos da base das vilosidades intestinais e na medula óssea, confirmando o diagnóstico de parvovirose. O peritônio sobre o rim direito estava espessado e revestido por células cuboides, formando múltiplas projeções papilares, nas quais observava-se acentuado infiltrado de células gigantes, macrófagos, linfócitos, eosinófilos e plasmócitos. Entre as projeções papilares havia ovos de Dioctophyma renale, áreas de necrose, calcificação e células gigantes. Conclui-se que a lontra, em função da fragmentação e degradação de seu habitat natural, aproximou-se do centro urbano e contaminou-se com o vírus, o qual é mantido e disseminado por animais domésticos. Por sua vez, a infecção por D. renale pode estar relacionada com a presença de animais domésticos parasitados, os quais eliminam ovos do helminto através da urina contaminando o ambiente, onde coabitam hospedeiros intermediários e paratênicos do parasito. As doenças desses animais podem ser um fator de declínio das populações de animais silvestres e alerta para o risco de spill-over na região
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