Search results for "zoología"
showing 10 items of 134 documents
A QUANTITATIVE APPROACH TO THE EXPERIMENTAL TRANSMISSION SUCCESS OF ECHINOSTOMA FRIEDI (TREMATODA: ECHINOSTOMATIDAE) IN RATS
2006
Using a range of parameters, the ability of rats (Rattus norvegicus) to successfully transmit Echinostoma friedi to the next host was examined under experimental conditions. The concept of Experimental Transmission Success (TM), defined as the number of hosts that become successfully infected after exposure to a number of infective stages produced by a previous host per unit of inoculation at which this latter host was exposed, was introduced. Using data for the egg output and miracidium hatching and infectivity, the TM permits us to estimate the ability of a particular defintive host species to successfully transmit a parasite species. This concept may be also useful to compare the transmi…
Gastrointestinal helminths of cuvier’s beaked whales, ziphius cavirostris, From the Western Mediterranean
2004
We examined the gastrointestinal helminth fauna of 2 Cuvier's beaked whales, Ziphius cavirostris, stranded on the Spanish Mediterranean coast. Information regarding intestinal parasites of this species is provided for the first time. Six helminth taxa were identified. Thirty type II larvae of the nematode Anisakis sp. were found in the stomach and the intestine of both hosts; 2 type I larvae of Anisakis sp. were found in the intestine of 1 host. One juvenile of the acanthocephalan Bolbosoma vasculosum was found in the intestine; the metacestode Scolex pleuronectis was found mainly in the terminal colon and the anal crypts of both hosts; adult cestodes of Tetrabothrius sp., which may represe…
Growth and emigration of third-stage larvae of Hysterothylacium aduncum (Nematoda: Anisakidae) in larval herring Clupea harengus
2000
The growth and emigration of Hystherothylacium aduncum in laboratory-reared herring larvae Clupea harengus was studied. Experimental infections of 36-day-old herring larvae resulted in 126 hosts infected with 306 H. aduncum larvae. Regression analyses showed a significant worm emigration from the rectum to the head of the fish, accompanied by an increase in worm body length. The emigration was independent of worm intensity, which suggests an ontogenetic process. Some worms departed from this pattern by moving posteriorly or by penetrating into the muscle, and in 5 cases, the larvae were observed to leave living fish. This individual variation has not been observed in previous studies and mi…
A new genus and species of asteraceae-inhabiting aphid (hemiptera: aphididae) from Costa Rica and Mexico
2013
P. 323-331 Ucrimyzus villalobosi Mier Durante & Pérez Hidalgo gen. n., sp. n. (Hemiptera: Aphididae: Macrosiphini) are described from apterous and alate viviparous females collected on species of genera Bidens, Schkuhria, Senecio and Stevia (Asteraceae: Asteroideae) in Costa Rica and Mexico. Principal components analysis (PCA) was done to verify that the studied aphids belong to a single species regardless of their geographical origin or host plant. Molecular analyses were carried out on the sequences of a fragment of the mitochondrial gene encoding for cytochrome c oxidase subunit 1 (COI) and of a fragment of the nuclear gene encoding elongation factor 1α (EF1α). The taxonomic discussion t…
Caracterización de los mecanismos moleculares y neuroendocrinos mediados por las kisspeptinas en el cerebro de machos de lubina europea (dicentrarchu…
2015
La kisspeptina es el producto peptídico del gen KISS1. Los primeros estudios que se llevaron a cabo en mamíferos, concretamente en humanos y en ratones, revelaron que ciertas mutaciones que inactivaban al receptor de la kisspeptina (GPR54) daban lugar al desarrollo de hipogonadismo hipogonadotrópico. Este hecho sugirió que el sistema KISS1/GPR54 juega un papel importante en la función reproductiva de los mamíferos. En los mamíferos placentarios hay un solo gen KISS1 y otro que codifica GPR54. Sin embargo en diferentes especies de teleósteos se ha descrito un segundo parálogo ancestral tanto de kiss1 como de gpr54-1b, denominados kiss2 y gpr54-2b, respectivamente. Los mecanismos funcionales,…
Estudio faunístico de los mosquitos (Díptera, Culicidae) de la comarca del Somontano de Barbastro y su posible relevancia en la difusión del paludismo
2013
Se han capturado 1.106 ejemplares larvarios de culícidos pertenecientes a 12 especies en la Comarca del Somontano de Barbastro, de las cuales dos (Culex impudicus y Cx. territans) se citan por primera en la provincia de Huesca. Pese a que la especie más abundante fue Cx. pipiens, desde un punto de vista epidemiológico señalar la elevada presencia de mosquitos del género Anopheles, potenciales vectores de la malaria, en diversas regiones de la comarca. Especialmente relevante es la destacada densidad que presenta An. atroparvus, importante vector palúdico, en biotopos concretos de la región más meridional del área de estudio. Adicionalmente, también se han detectado especies muy antropofílic…
Holidays? Not for all. Eagles have larger home ranges on holidays as a consequence of human disturbance
2019
Human-wildlife conflicts are the object of raising concern in conservation biology. People living in urban areas are rapidly increasing worldwide and consequently the temporal pattern of occupation of natural areas for recreation is changing as well, resulting in an ever-increasing concentration of people during weekends and holidays. This is particularly evident in affluent societies, where more recreationists visit natural areas on holidays and weekends, causing disturbance to wildlife in the so-called “weekend effect”. Here, we tested the response to disturbance of 30 Bonelli's eagles tracked by high-frequency GPS/GSM telemetry. We analysed daily home-range size, a measure of changing be…
Sevend Pounds y Biología. Zoología y transplante de órganos en el epílogo del film, una experiencia en formación de docente
2015
Las experiencias didácticas vividas en formación docente inicial tienen un fuerte impacto en la conformación del perfil profesional del profesor. Estas deben ser coincidente con los fines que se tienen para la enseñanza de las ciencias en el nivel educativo medio: formar ciudadanos críticos. Propuestas de enseñanza de la zoología con un enfoque CTS ofrecen una visión integrada, interdisciplinar, y problematizadora del saber científico, que conectan la ciencia con la realidad que vive el individuo en la sociedad. La utilización del cine como recurso didáctico permite vincular de manera muy favorable los avances científicos y tecnológicos con aspectos sociales. La experiencia didáctica que pr…
Effectiveness of different vaccine formulations against vibriosis caused by Vibrio vulnificus serovar E (biotype 2) in European eels Anguilla anguilla
2001
Vibriosis due to Vibrio vulnificus serovar E (biotype 2) is one of the main causes of mortality in European eels cultured in Europe. The main objective of this study was to develop a vaccine and a vaccination procedure against this pathogen. With this aim, we tested several vaccine formulations (inactivated whole-cells with and without toxoids‹inactivated extracellular products‹from capsulated and uncapsulated strains, attenuated live vaccines and purified lipopolysaccharide [LPS]) on eels maintained under controlled laboratory conditions using different delivery routes (injection and immersion). To study the immune response we estimated antibody titers and bactericidal/bacteriostatic activ…
Field testing of a vaccine against eel diseases caused by Vibrio vulnificus
2001
The field results of a vaccination programme against Vibrio vulnificus serovar E (biotype 2) in a Spanish eel farm are reported. A total of 9.5 million glass eels were vaccinated from January 1998 to March 2000 by prolonged immersion followed by 2 subsequent reimmunisations after 12 to 14 and 24 to 28 d, respectively. The acquired protection and the immune response against serovar E were estimated over a period of 6 mo after vaccination. A similar vaccination schedule was conducted with elvers in a Danish eel farm. In this case, the acquired protection and the immune response against serovar E and the new eel-pathogenic serovars, recently described in Denmark, were evaluated over a short te…