Search results for "MNA"
showing 10 items of 1167 documents
Relación entre la actividad física, los hábitos alimentarios y el consumo y actitud hacia las drogas en un instituto valenciano
2013
El presente estudio tiene como objetivo conocer el interés por la actividad física y la práctica deportiva de 224 (111 chicos y 113 chicas) alumnos de Educación Secundaria Obligatoria y Bachillerato en un instituto de la ciudad de Valencia, así como relacionar dichos hábitos con la alimentación y el consumo de drogas. Para realizar el estudio se utilizó un cuestionario de elaboración propia, formado por veintitrés ítems de los cuales se extrajeron los resultados. Los resultados mostraron que los adolescentes estudiados tienen, en general, buenos hábitos deportivos aunque obtienen peores valores en los hábitos de consumo de sustancias o tiempo dedicado a las nuevas tecnologías. En lo que se …
Evidence of enhanced bacterial invasion during Diplostomum spathaceum infection in European grayling, Thymallus thymallus (L.)
2006
Farmed grayling, Thymallus thymallus (L.), are susceptible to atypical Aeromonas salmonicida (aAS) infections. Interactions between bacteria and parasites were studied using grayling subjected to concomitant exposure to aAS bacteria and the digenean parasite Diplostomum spathaceum. Atypical AS was detected from fish by a combination of bacterial cultivation and polymerase chain reaction techniques. A detection level of 17 aAS cells per 100 mg intestine tissue sample was obtained. Concomitant bacterial exposure did not enhance the severity of grayling eye rupture and nuclear extrusion induced by D. spathaceum, but D. spathaceum invasion into grayling increased the proportion of fish carrying…
Immunostimulants in prevention of columnaris disease of rainbow trout, Oncorhynchus mykiss (Walbaum).
2009
Characterisation of fascioliasis lymnaeid intermediate hosts from Chile by DNA sequencing, with emphasis on Lymnaea viator and Galba truncatula.
2011
In South America, Fasciola hepatica infection poses serious health problems in both humans and livestock. In Chile, the medical impact appears yearly stable and mainly concentrated in central regions, where the veterinary problem is highlighted by higher animal prevalences. Studies were undertaken by rDNA ITS-2 and ITS-1 and mtDNA cox1 sequencing to clarify the specific status of the lymnaeids, their geographical distribution and fascioliasis transmission capacity in Chile, by comparison with other American countries and continents. Results change the lymnaeid scenario known so far. The lymnaeid fauna of mainland Chile shows to be poor, including only two authochthonous species, Lymnaea via…
Chondroitin AC lyase activity is related to virulence of fish pathogenic Flavobacterium columnare.
2006
The virulence of eight Flavobacterium columnare strains was studied to find correlations between several virulence-related factors and virulence. Virulence was tested in vivo using rainbow trout, Oncorhynchus mykiss (Walbaum). Suggested virulence-related factors such as production of the degradative enzyme chondroitin lyase, plasmid occurrence and adhesion capability were studied in vitro. Infection with the four most virulent strains resulted in 95-100% mortality within 114 h. Chondroitin lyase activity was found to be significantly related to the virulence of the strains at 25 degrees C and it was also shown to be temperature-dependent, being higher at 25 degrees C than at 20 degrees C. V…
Fasciola gigantica transmission in the zoonotic fascioliasis endemic lowlands of Guilan, Iran: experimental assessment.
2014
The lowland flatlands around the city of Bandar-Anzali, at the Caspian Sea shore, Guilan province, are an endemic area where Fasciola gigantica appears to be the fasciolid species involved and past outbreaks affecting around 15,000 people and the highest human infection rates in Iran have been reported. Fascioliasis transmission in that area has been experimentally analysed for the first time, by means of assays of monomiracidial (Group A: 120 snails) and pentamiracidial (Group B: 96 snails) infections of local Radix lymnaeid snails with a local cattle F. gigantica isolate. Ribosomal DNA ITS-2 sequencing proved that Lymnaea (Radix) gedrosiana should henceforth be considered a synonym of Rad…
Transmission, infectivity and survival of Diplostomum spathaceum cercariae
2003
The transmission dynamics of the cercariae of Diplostomum spathaceum were investigated under laboratory conditions using cercariae collected from naturally infected Lymnaea stagnalis. Cercariae were kept in a constant temperature of 20 °C and the survival and infectivity to naïve young rainbow trout recorded at 3-h intervals until few cercariae were alive. Mortality initially remained constant but increased rapidly after 20 h. While a model of constant mortality fitted the survival data, an age-dependent model provided a better fit and implied that cercariae tended to carry similar quantities of resources and once these were exhausted the cercariae died. Cercarial infectivity also showed an…
Influence of rearing conditions on Flavobacterium columnare infection of rainbow trout, Oncorhynchus mykiss (Walbaum).
2005
The influence of rearing conditions on Flavobacterium columnare infection of rainbow trout, Oncorhynchus mykiss (Walbaum), was studied experimentally in the laboratory and at a fish farm. In experiment I, the effect of parasitic infection on columnaris disease was studied using F. columnare carrier fish. The fish were exposed to Diplostomum spathaceum cercariae and a set of other stressors in order to induce clinical columnaris infection. Parasitic infection and other stressors failed to induce the disease. Disease occurred when the fish were challenged with F. columnare, but D. spathaceum infection did not enhance the severity of the infection. In experiment II, the influence of rearing de…
Environment may be the source of Flavobacterium columnare outbreaks at fish farms
2012
Summary Flavobacterium columnare, causing columnaris disease, was isolated for the first time from free water and biofilms in the environment outside fish farms. Fourteen isolates were found from Central Finland from a river by a water intake of a salmonid farm and 400 m upstream of the farm. One isolate was from a lake not under the influence of any fish farming. The bacterium could not be isolated from five other lakes in Central Finland or from three lakes in Eastern Finland, none of them in use for fish farming. Among the environmental isolates there was both genetic variability and difference in virulence, but the isolates were less virulent than the isolates originating from a disease…