5 research outputs found
Moluscos dulceacu铆colas ex贸ticos en Chile Exotic freshwater mollusks in Chile
Las especies de moluscos ex贸ticas dulceacu铆colas registradas en esta contribuci贸n, corresponden a ejemplares recolectados en humedales en acuarios comerciales o interceptados en barreras aduaneras, as铆 como de referencias bibliogr谩ficas. Un total de 7 especies pertenecientes a 6 g茅neros fueron identificadas: Pomacea bridgesii; Helobia sp.; Thiara (Melanoides) tuberculata; Melanoides maculata; Physa sp.; Physella venustula y Biomphalaria sp. Melanoides maculata fue recolectada en el r铆o Lluta y clasificada como especie criptog茅nica. Los moluscos ex贸ticos recolectados podr铆an tener 茅xito en su establecimiento si se considera la vulnerabilidad de los h谩bitats nativos debido al cambio en las condiciones clim谩ticas globales o a las elevaciones t茅rmicas producidas en el sector costero por los fen贸menos de El Ni帽o. En este sentido, las especies subtropicales observadas se podr铆an considerar como no end茅micas y vectores potenciales de zoonosis parasitarias. Las principales v铆as de introducci贸n de moluscos dulceacu铆colas ex贸ticos se derivaron del intercambio comercial, por lo cual, y frente a su incremento interregional, se hace necesario recopilar datos ecol贸gicos y taxon贸micos adecuados que permitan evaluar el riesgo de su establecimiento, as铆 como servir de base para la aplicaci贸n de futuros tratamientos en bioseguridad.The exotic freshwater mollusk species we report here were collected in wetlands, commercial aquariums, or were given to us by government officials who intercepted some exotic species at customs offices. Other records came from the specialized literature. These species are Pomacea bridgesii; Helobia sp.; Thiara (Melanoides) tuberculata; Melanoides maculata; Physa sp., Physella venustula and Biomphalaria sp. It is not clear how Melanoides maculata, found in the R铆o Lluta, reached Chile. The exotic species collected could expand their ranges in Chilean territory given global environmental and climate change or the rises in temperature produced in the Chilean coastal areas by the oceanographic El Ni帽o events. Especially important are the subtropical mollusk species which are intermediate hosts/vectors of animal-borne parasitic diseases. The main route of introduction for these exotic freshwater species of mollusks has been commercial trade, either as a voluntary or a deliberate activity, especially due to the increase in commercial activity in the south-eastern Pacific. It is necessary to gather as much information as possible about exotic species to evaluate the possibility of their becoming established and to compile basic information to be applied for bio-security purposes in the future
Infecci贸n experimental de Erysipelothrix rhusiopathiae en un pez de agua dulce (cheirodon pisciculus)
Con el objeto de conocer la capacidad de infectar el pez Cheirodon pisciculus,聽se realiz贸 la inoculaci贸n experimental del serotipo 4 y de un serotipo Nuevo recientemente descrito de Erysipelothrix rhusiopathiae,聽aislados de artritis de cerdo. Se emple贸 96 peces distribuidos de 16 en seis peceras. Los grupos se inocularon para cada serotipo por las v铆as de inmersi贸n simple y de escarificaci贸n e inmersi贸n con 8 x 105聽UFC/ml, manteniendo dos grupos controles no inoculados: uno escarificado y otro sin tratamiento. Los seis grupos fueron observados diariamente durante 14 d铆as postinoculaci贸n para registrar modificaciones de conducta a est铆mulos de alimentaci贸n, ac煤sticos y visuales. En los d铆as 3, 7, 10 y 14 postinoculaci贸n, se sacrific贸 cuatro peces por grupo, obteni茅ndose de cada uno muestra de ri帽贸n posterior, para el aislamiento e identificaci贸n de E. rhusiophatiae.Los dos grupos de peces infectados con serotipo Nuevo disminuyeron el apetito especialmente entre los d铆as dos y ocho postinoculaci贸n y reaccionaron marcadamente a est铆mulos de movimiento y sonido desde el d铆a tres postinoculaci贸n hasta el final de la experiencia. Todos los cambios fueron m谩s moderados en el grupo inoculado s贸lo por inmersi贸n. Los grupos inoculados con serotipo 4, al igual que los grupos controles, no manifestaron cambios de comportamiento. Al cultivo bacteriano, s贸lo hubo aislamiento de E. rhusiopathiae聽en los peces de los grupos tratados con serotipo Nuevo, en 2/16 infectados por inmersi贸n y en 10/16 infectados por escarificaci贸n e inmersi贸n.Palabras claves: Erysipelothrix rhusiopathiae,聽inoculaci贸n experimental, infecci贸n en peces, peces.AbstractIn order to know the capacity of the Cheirodon pisciculus聽fish to be infected, strains of serotype 4 and of a new serotype of Erysipelothrix rhusiopathiae聽isolated from pig arthritis were experimentaly inoculated. Ninety six fish in groups of 16 were distributed in six aquaria. Two groups per serotype were inoculated by simple dipping or scratching and dipping into 8 x 105聽CFU/ml bacterial suspension. There were two control groups, one scratched and the other without treatment. The six groups were daily observed during 14 post inoculation days to register behaviour changes to visual, acustic and feeding stimula. At the 3, 7, 10 and 14 post inoculation day four fish per group were slaughtered to get back kidney sample for isolation of E. rhusiopathiae.The two infected groups with the new serotype diminished their appetite specially during 2nd to 8th post inoculation day and reacted notably to sound and movement stimula from 3rd post inoculation day till the end of the experience. More moderate changes were observed in those inoculated by simple dipping. Inoculated with serotype 4 and control groups did not show behaviour changes. E. rhusiopathiae聽bacteria was isolated only in inoculted with new serotype groups, 2/16 infected by simple dipping and 10/16 infected by scratching and dipping.Key words: Erysipelothrix rhusiopathiae,聽experimental inoculation, infected fish, fish.
Infecci贸n experimental de Erysipelothrix rhusiopathiae en un pez de agua dulce (cheirodon pisciculus)
Con el objeto de conocer la capacidad de infectar el pez Cheirodon pisciculus,聽se realiz贸 la inoculaci贸n experimental del serotipo 4 y de un serotipo Nuevo recientemente descrito de Erysipelothrix rhusiopathiae,聽aislados de artritis de cerdo. Se emple贸 96 peces distribuidos de 16 en seis peceras. Los grupos se inocularon para cada serotipo por las v铆as de inmersi贸n simple y de escarificaci贸n e inmersi贸n con 8 x 105聽UFC/ml, manteniendo dos grupos controles no inoculados: uno escarificado y otro sin tratamiento. Los seis grupos fueron observados diariamente durante 14 d铆as postinoculaci贸n para registrar modificaciones de conducta a est铆mulos de alimentaci贸n, ac煤sticos y visuales. En los d铆as 3, 7, 10 y 14 postinoculaci贸n, se sacrific贸 cuatro peces por grupo, obteni茅ndose de cada uno muestra de ri帽贸n posterior, para el aislamiento e identificaci贸n de E. rhusiophatiae.Los dos grupos de peces infectados con serotipo Nuevo disminuyeron el apetito especialmente entre los d铆as dos y ocho postinoculaci贸n y reaccionaron marcadamente a est铆mulos de movimiento y sonido desde el d铆a tres postinoculaci贸n hasta el final de la experiencia. Todos los cambios fueron m谩s moderados en el grupo inoculado s贸lo por inmersi贸n. Los grupos inoculados con serotipo 4, al igual que los grupos controles, no manifestaron cambios de comportamiento. Al cultivo bacteriano, s贸lo hubo aislamiento de E. rhusiopathiae聽en los peces de los grupos tratados con serotipo Nuevo, en 2/16 infectados por inmersi贸n y en 10/16 infectados por escarificaci贸n e inmersi贸n.Palabras claves: Erysipelothrix rhusiopathiae,聽inoculaci贸n experimental, infecci贸n en peces, peces.AbstractIn order to know the capacity of the Cheirodon pisciculus聽fish to be infected, strains of serotype 4 and of a new serotype of Erysipelothrix rhusiopathiae聽isolated from pig arthritis were experimentaly inoculated. Ninety six fish in groups of 16 were distributed in six aquaria. Two groups per serotype were inoculated by simple dipping or scratching and dipping into 8 x 105聽CFU/ml bacterial suspension. There were two control groups, one scratched and the other without treatment. The six groups were daily observed during 14 post inoculation days to register behaviour changes to visual, acustic and feeding stimula. At the 3, 7, 10 and 14 post inoculation day four fish per group were slaughtered to get back kidney sample for isolation of E. rhusiopathiae.The two infected groups with the new serotype diminished their appetite specially during 2nd to 8th post inoculation day and reacted notably to sound and movement stimula from 3rd post inoculation day till the end of the experience. More moderate changes were observed in those inoculated by simple dipping. Inoculated with serotype 4 and control groups did not show behaviour changes. E. rhusiopathiae聽bacteria was isolated only in inoculted with new serotype groups, 2/16 infected by simple dipping and 10/16 infected by scratching and dipping.Key words: Erysipelothrix rhusiopathiae,聽experimental inoculation, infected fish, fish.
Population biology of Trichomycterus sp. (Siluriformes, Trichomycteridae) in Passa Cinco stream, Corumbata铆 River sub-basin, S茫o Paulo State, southeastern Brazil
The aim of this work was to characterise the population of Trichomycterus sp. in Passa Cinco stream, regarding length structure, sex ratio, diet and reproductive aspects, in accordance with drought and rainy season periods and longitudinal gradient, as well as to analyse its corporal condition in a temporal dimension. Six samplings were accomplished with the use of electric fishing equipment in three different sites in Passa Cinco stream, contemplating sites of order two, three and four, during the months of May, July, September and November of 2005; and January and March of 2006. Three hundred and forty one individuals were captured, composed of 203 males, 99 females and 39 immatures. The smallest captured individual, an immature, presented 28 mm of standard length and the largest, a male, 85 mm. There was not significant variation in repletion degree and accumulated fat in the visceral cavity of the individuals analysed during the considered periods. Eleven different food items were found in the stomach contents. Considering the whole sampling period, immature Diptera was a preferential item and other items were found as occasionally ingested. Spearman and Friedman tests did not find significant differences in the diet of Trichomycterus sp. in the periods and sampling sites, respectively. The average of absolute fecundity was of 73 oocytes, and the parceled type of spawning was performed. Both males and females of Trichomycterus sp. presented significant differences in their corporal conditions in the considered periods, and in the rainy season, these fishes were in better condition