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1.
Sci Rep ; 7(1): 17102, 2017 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-29213103

RESUMEN

The pervasive and unabated nature of global amphibian declines suggests common demographic responses to a given driver, and quantification of major drivers and responses could inform broad-scale conservation actions. We explored the influence of climate on demographic parameters (i.e., changes in the probabilities of survival and recruitment) using 31 datasets from temperate zone amphibian populations (North America and Europe) with more than a decade of observations each. There was evidence for an influence of climate on population demographic rates, but the direction and magnitude of responses to climate drivers was highly variable among taxa and among populations within taxa. These results reveal that climate drivers interact with variation in life-history traits and population-specific attributes resulting in a diversity of responses. This heterogeneity complicates the identification of conservation 'rules of thumb' for these taxa, and supports the notion of local focus as the most effective approach to overcome global-scale conservation challenges.


Asunto(s)
Anfibios/fisiología , Conservación de los Recursos Naturales , Animales , Cambio Climático , Europa (Continente) , América del Norte , Dinámica Poblacional , Estaciones del Año , Urodelos/fisiología
2.
Vet Pathol ; 54(4): 686-694, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28494706

RESUMEN

Amphibian pathogens are of current interest as contributors to the global decline of amphibians. However, compared with chytrid fungi and ranaviruses, herpesviruses have received relatively little attention. Two ranid herpesviruses have been described: namely, Ranid herpesvirus 1 (RHV1) and Ranid herpesvirus 2 (RHV2). This article describes the discovery and partial characterization of a novel virus tentatively named Ranid herpesvirus 3 (RHV3), a candidate member of the genus Batrachovirus in the family Alloherpesviridae. RHV3 infection in wild common frogs (Rana temporaria) was associated with severe multifocal epidermal hyperplasia, dermal edema, a minor inflammatory response, and variable mucous gland degeneration. Intranuclear inclusions were numerous in the affected epidermis together with unique extracellular aggregates of herpesvirus-like particles. The RHV3-associated skin disease has features similar to those of a condition recognized in European frogs for the last 20 years and whose cause has remained elusive. The genome of RHV3 shares most of the features of the Alloherpesviruses. The characterization of this presumptive pathogen may be of value for amphibian conservation and for a better understanding of the biology of Alloherpesviruses.


Asunto(s)
Dermatitis/veterinaria , Infecciones por Herpesviridae/veterinaria , Herpesviridae , Rana temporaria/virología , Animales , Animales Salvajes/virología , Dermatitis/patología , Herpesviridae/genética , Herpesviridae/aislamiento & purificación , Infecciones por Herpesviridae/patología , Infecciones por Herpesviridae/virología , Filogenia , Reacción en Cadena de la Polimerasa/veterinaria , Análisis de Secuencia de ADN/veterinaria , Piel/patología , Piel/virología , Suiza
3.
Science ; 346(6209): 630-1, 2014 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-25359973

RESUMEN

Emerging infectious diseases are reducing biodiversity on a global scale. Recently, the emergence of the chytrid fungus Batrachochytrium salamandrivorans resulted in rapid declines in populations of European fire salamanders. Here, we screened more than 5000 amphibians from across four continents and combined experimental assessment of pathogenicity with phylogenetic methods to estimate the threat that this infection poses to amphibian diversity. Results show that B. salamandrivorans is restricted to, but highly pathogenic for, salamanders and newts (Urodela). The pathogen likely originated and remained in coexistence with a clade of salamander hosts for millions of years in Asia. As a result of globalization and lack of biosecurity, it has recently been introduced into naïve European amphibian populations, where it is currently causing biodiversity loss.


Asunto(s)
Quitridiomicetos , Enfermedades Transmisibles Emergentes/veterinaria , Especies en Peligro de Extinción , Micosis/veterinaria , Urodelos/microbiología , Animales , Biodiversidad , Enfermedades Transmisibles Emergentes/microbiología , Micosis/microbiología , Filogenia , Urodelos/clasificación
4.
J Evol Biol ; 18(2): 415-25, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15715847

RESUMEN

Species that occupy similar habitats are expected to show convergent phenotypes. If habitats are defined by the presence of predators, then traits that modify vulnerability to predation, including predator-induced phenotypic plasticity, should be similar within habitats. We tested this idea using larvae of six syntopic newt species belonging to the two Triturus clades. Behavioural plasticity induced by odonate predators was strongly dissimilar between the two main clades but similar within them. Morphological plasticity was variable among species, even between one pair of closely related species. A predation experiment tested whether differences between clades could be caused by differences in body size. Size-specific vulnerability differed between newts in the small-bodied and large-bodied clades, indicating that similar predators may affect the two clades differently. The results showed both similarity and dissimilarity in predator-induced phenotypic plasticity in syntopic larval newts although theory suggests that divergence is unlikely in such ecologically similar species.


Asunto(s)
Conducta Animal/fisiología , Ambiente , Fenotipo , Filogenia , Salamandridae/fisiología , Animales , Pesos y Medidas Corporales , Insectos/fisiología , Larva/fisiología , Conducta Predatoria/fisiología , Salamandridae/genética , Especificidad de la Especie
5.
Vet Comp Oncol ; 3(2): 73-80, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19379215

RESUMEN

Invasive transitional cell carcinoma (TCC) of the urinary bladder responds poorly to medical therapy. Combining platinum chemotherapy with a cyclooxygenase (cox) inhibitor has shown promise against canine TCC, where the disease closely mimics the human condition. A phase II clinical trial of carboplatin combined with the cox inhibitor, piroxicam, was performed in 31 dogs with naturally occurring, histopathologically confirmed, measurable TCC. Complete tumour staging was performed before and at 6-week intervals during therapy. Tumour responses in 29 dogs included 11 partial remissions, 13 stable disease and five progressive disease. Two of the 31 dogs were withdrawn prior to the re-staging of the tumour. Gastrointestinal toxicity was observed in 23 dogs. Hematologic toxicity was noted in 11 dogs. The median survival was 161 days from first carboplatin treatment to death. In conclusion, carboplatin/piroxicam induced remission in 40% of dogs providing evidence that a cox inhibitor enhances the antitumour activity of carboplatin. The frequent toxicity and limited survival, however, do not support the use of this specific protocol against TCC.

6.
J Am Vet Med Assoc ; 218(11): 1783-6, 2001 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-11394830

RESUMEN

OBJECTIVE: To evaluate the use of piroxicam for the treatment of oral squamous cell carcinoma in dogs. DESIGN: Prospective case series. ANIMALS: 17 dogs with measurable oral squamous cell carcinoma. PROCEDURE: Dogs were treated with piroxicam at a dosage of 0.3 mg/kg (0.14 mg/lb) of body weight, PO, every 24 hours until progressive disease or unacceptable signs of toxicosis developed or the dog died. RESULTS: One dog had a complete remission (maxillary tumor), and 2 dogs had partial remissions (lingual tumor and tonsillar tumor). An additional 5 dogs had stable disease, including 1 with a maxillary tumor, 2 with mandibular tumors, and 2 with tonsillar tumors. Variables associated with tumor response were not identified. Median and mean times to failure for the 3 dogs that had a remission were 180 and 223 days, respectively. Median and mean times to failure for the 5 dogs with stable disease were 102 and 223 days, respectively. Time to failure was positively associated with tumor response and negatively associated with tumor size. One dog had mild adverse gastrointestinal tract effects that resolved with the addition of misoprostol to the treatment regimen. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that piroxicam may be useful in the treatment of dogs with oral squamous cell carcinoma; response rate was similar to that reported for other cytotoxic treatments. Larger-scale studies are warranted to determine what role piroxicam may have, alone or in combination with other treatments, for the treatment of dogs with oral squamous cell carcinoma.


Asunto(s)
Antiinflamatorios no Esteroideos/uso terapéutico , Carcinoma de Células Escamosas/veterinaria , Enfermedades de los Perros/tratamiento farmacológico , Neoplasias de la Boca/veterinaria , Piroxicam/uso terapéutico , Animales , Antiinflamatorios no Esteroideos/efectos adversos , Carcinoma de Células Escamosas/tratamiento farmacológico , Perros , Evaluación de Medicamentos/veterinaria , Femenino , Masculino , Neoplasias de la Boca/tratamiento farmacológico , Piroxicam/efectos adversos , Factores de Tiempo , Insuficiencia del Tratamiento , Resultado del Tratamiento
7.
Nature ; 404(6779): 752-5, 2000 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-10783886

RESUMEN

Although there is growing concern that amphibian populations are declining globally, much of the supporting evidence is either anecdotal or derived from short-term studies at small geographical scales. This raises questions not only about the difficulty of detecting temporal trends in populations which are notoriously variable, but also about the validity of inferring global trends from local or regional studies. Here we use data from 936 populations to assess large-scale temporal and spatial variations in amphibian population trends. On a global scale, our results indicate relatively rapid declines from the late 1950s/early 1960s to the late 1960s, followed by a reduced rate of decline to the present. Amphibian population trends during the 1960s were negative in western Europe (including the United Kingdom) and North America, but only the latter populations showed declines from the 1970s to the late 1990s. These results suggest that while large-scale trends show considerable geographical and temporal variability, amphibian populations are in fact declining--and that this decline has been happening for several decades.


Asunto(s)
Anfibios/fisiología , Animales , Dinámica Poblacional
8.
J Am Anim Hosp Assoc ; 35(4): 311-8, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10416776

RESUMEN

In this report, the authors describe four dogs referred for diagnosis and treatment of unusual and aggressive testicular tumors. For the vast majority of dogs with testicular tumors, orchiectomy is curative. All dogs in this report had surgical resection, and three of four dogs were treated with cisplatin chemotherapy. Cisplatin is widely recognized as the most active agent in testicular cancer in human medicine.


Asunto(s)
Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/terapia , Seminoma/veterinaria , Tumor de Células de Sertoli/veterinaria , Neoplasias Testiculares/veterinaria , Animales , Perros , Masculino , Seminoma/diagnóstico , Seminoma/terapia , Tumor de Células de Sertoli/diagnóstico , Tumor de Células de Sertoli/terapia , Neoplasias Testiculares/diagnóstico , Neoplasias Testiculares/terapia
9.
Trends Ecol Evol ; 11(6): 253-4, 1996 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21237833
10.
Trends Ecol Evol ; 9(2): 62, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21236768
11.
J Vet Intern Med ; 7(2): 65-7, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-7684785

RESUMEN

Recombinant canine granulocyte colony-stimulating factor (rcG-CSF) was administered subcutaneously at a dosage of 5 micrograms/kg/day to five healthy, young adult cats for 42 days. Mean neutrophil counts +/- standard deviation increased significantly (P < 0.001) from 10,966/microL +/- 2324 to 30,688/microL +/- 5296 within 24 hours after administration of the first dosage of rcG-CSF. Mean neutrophil counts reached 52,978/microL +/- 11,207 on day 6, representing a second significant increase (P < 0.01) over the previous 5 days. Mean neutrophil counts continued to increase, reaching 66,994/microL +/- 12,419 on day 14, then remaining within a range of 66,994 to 87,839/microL throughout the remainder of the study. The maximum mean neutrophil count was 87,839/microL +/- 8,695 on day 42. Neutrophil counts remained high until the administration of recombinant canine granulocyte colony-stimulating factor was discontinued 42 days after initiation of therapy. Once the rcG-CSF administration was discontinued, neutrophil counts returned to pretreatment values within 5 days. There were no significant changes in numbers of any of the other cell lines. There was no clinically significant toxicosis associated with the administration of rcG-CSF.


Asunto(s)
Gatos/sangre , Factor Estimulante de Colonias de Granulocitos/farmacología , Neutrófilos/efectos de los fármacos , Animales , Perros , Femenino , Recuento de Leucocitos/veterinaria , Masculino , Proteínas Recombinantes/farmacología
12.
Trends Ecol Evol ; 8(8): 271-3, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21236166
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