Isolation and characterization of 8 microsatellite loci for the ‘‘killer shrimp’’, an invasive Ponto-Caspian amphipod Dikerogammarus villosus (Crustacea: Amphipoda)

Dikerogammarus villosus is a freshwater amphipod of the Ponto-Caspian origin recognized as one of the 100 worst alien species in Europe, having negative impact on biodiversity and functioning of the invaded aquatic ecosystems. The species has a wide ecophysiological tolerance and during the last 20 years it has rapidly spread throughout European inland waters. In consequence, it presents a major conservation management problem. We describe eight polymorphic microsatellite loci developed for D. villosus by combining a biotin-enrichment protocol and new generation 454GS-FLX Titanium pyrosequencing technology. When genotyped in 64 individuals from two locations, the loci exhibited a mean diversity of 4.87 alleles per locus (2–13). The mean observed and expected heterozygosities were, respectively, 0.439 (0.091–0.844) and 0.468 (0.089–0.843). Gametic disequilibrium was not detected for any pair of loci. The microsatellite markers will be a valuable tool in assessing the demographic processes associated with invasion of the killer shrimp from a genetic point of view

Dikerogammarus villosus (Sowinsky, 1894) (Crustacea, Amphipoda) colonizes next alpine lake – Lac du Bourget, France.

4 pagesDikerogammarus villosus has been recorded for the first time in the alpine lake – Lac du Bourget, French Alps. Low abundance of the alien species in gathered samples suggests that the colonization is just in its initial stage. Two native gammarid species: Gammarus fossarum (Koch, 1835) and G. pulex (Linnaeus, 1758) are still present in the lake. The invader has most probably reached the lake through the Canal de Savières joining the lake to the Rhone River in which it has been already present since late 1990s

A co-invasive microsporidian parasite that reduces the predatory behaviour of its host Dikerogammarus villosus (Crustacea, Amphipoda).

5 pagesInternational audienceParasites are known to affect the predatory behaviour or diet of their hosts. In relation to biological invasions, parasites may significantly influence the invasiveness of the host population and/or mediate the relationships between the invader and the invaded community. Dikerogammarus villosus, a recently introduced species, has had a major impact in European rivers. Notably, its high position in trophic web and high predatory behaviour, have both facilitated its invasive success, and affected other macroinvertebrate taxa in colonized habitats. The intracellular parasite Cucumispora dikerogammari, specific to D. villosus, has successfully dispersed together with this amphipod. Data presented here have shown that D. villosus infected by this parasite have a reduced predatory behaviour compared with healthy individuals, and are much more active suggesting that the co-invasive parasite may diminish the predatory pressure of D. villosus on newly colonized communities

Is the host or the parasite the most locally adapted in an amphipod-acanthocephalan relationship? A case study in a biological invasion context.

8 pagesInternational audienceManipulative endoparasites with complex life cycles can alter their intermediate host immunity and behaviour in ways that increase survival probability within the host body cavity and enhance successful transmission to the definitive host. These parasitic manipulations are variable among and within parasite species and may result from co-evolutionary processes, in which the parasite is constrained for adaptation to the local intermediate host. Hence, arrival of a new host species in a local host population may promote local parasite maladaptation. This study tested the occurrence of local adaptation in two distantly located populations of the acanthocephalan parasite Pomphorhynchus laevis and its effect on the immunity and behaviour of its gammarid intermediate host Gammarus roeseli. This was done in France (an area for which G. roeseli is a recent invader) and Hungary (an area from which G. roeseli was believed to be native). As expected, we found no alteration in G. roeseli's immune defence and behaviour associated with infection by P. laevis in localities, where the gammarid is invasive. Unexpectedly, we found similar results in Hungarian populations, where the parasite was even more exposed to the host immune response. Whilst these results suggest maladaptation of the parasite to the gammarid in both countries, they also suggest that the gammarid host might be locally adapted to the parasite. Genetic analyses were performed on both the parasite and the host and the results suggest that the two subsets of populations we studied harbour rather isolated host-parasite systems, both probably deriving from a common ancestral population. We propose that G. roeseli is also of recent acquisition in Hungary, and that a recent co-evolutionary history between P. laevis and G. roeseli in association with a long generation time in the parasite has constrained parasite adaptations in Europe or even favoured host adaptation to the parasite

DataPlosOne

Capture mark recapture data (from summer 1995 to winter 2010) for greater flamingos captured as fledglings and ringed between 1995 and 1998 which were genotyped for microsatellite multi-locus heterozygosity. Body condition of fledgling also provided

Microsporidian disease of the invasive amphipod Dikerogammarus villosus and the potential for its transfer to local invertebrate fauna.

12 pagesInternational audienceInvasive species may introduce novel pathogens to a colonised area. Most of the time emerging pathogens are detected a posteriori, but recognition of a priori emergence of an invasive disease by host shift may be useful for predictive purposes. Here, we studied if the microsporidian parasite Cucumispora dikerogammari infecting the invasive Ponto-Caspian amphipod Dikerogammarus villosus, has the potential to become an emergent disease in invaded rivers in Western and Central Europe. We first showed that this parasite decreases the survival of D. villosus in the later stages of infection development. However, the host reproduces earlier in response to the infection, which could potentially reduce the negative impact of the parasite on host populations. Cucumispora dikerogammari is able to infect other crustacean species as revealed by our experimental infections. However, field census showed that it was found in other Ponto-Caspian species of amphipods only when it was observed in high prevalence in its native host, and when this host was at moderate frequencies in the community. Therefore, adaptation of C. dikerogammari to native gammaridean hosts has probably not been realized in the wild yet. However, since several environmental factors may promote future adaptations of the parasite to novel host species, we suggest C. dikerogammari should be included in surveillance networks for emergent disease in freshwater

Estudio de filtros cerámicos impregnados con plata coloidal, como un sistema de tratamiento de agua para procesos agroindustriales

TesisEl presente trabajo de investigación tuvo como objetivo evaluar la factibilidad de la utilización de filtros cerámicos, conformados por jipi de quinua (Chenopodium quinoa Willd.) y arcilla, impregnadas con plata coloidal, como alternativa para la potabilización de agua cruda de pozo para procesos agroindustriales. En el análisis microbiológico se utilizaron los métodos de Número Más Probable y Unidades Formadoras de Colonia, en el análisis fisicoquímico se utilizaron los métodos electrométrico, colorimétrico y volumétrico y para la determinación del caudal se utilizó el método volumétrico. De acuerdo a la caracterización microbiológica y fisicoquímica del agua cruda de pozo, se tiene que no cumplen con los límites máximos permisibles exigidos por el Ministerio de Salud. Para su tratamiento se elaboraron filtros a diferentes proporciones de jipi de quinua y arcilla (20/80; 30/70; 40/60) % e impregnados con plata coloidal a diferentes concentraciones (20; 35; 55) ppm. La evaluación estadística de la efectividad de los filtros en la eliminación de carga microbiológica y variación de características fisicoquímicas del agua cruda de pozo, fue contrastado bajo el diseño completamente al azar, basado en un arreglo factorial de 3x3x3, haciendo 27 observaciones con un nivel de significancia al 5%. Donde se optimizaron los tratamientos con el análisis de varianza, que tuvo diferencia estadística altamente significativa y el método de comparación múltiple Duncan nos indica el mejor tratamiento: tratamiento 1 (filtro 01 con 20% jipi de quinua y 80% arcilla y concentración de plata coloidal 55 ppm) con un caudal de 0.474 L/min, el cual presenta la mayor eliminación de carga microbiológica: coliformes totales 0 NMP/100 ml, coliformes fecales 0 NMP/100 ml, bacterias heterotróficas 0 UFC/ml y a la vez tiene una mayor variación de características fisicoquímicas: Conductividad eléctrica (900 µS/cm), Turbiedad (0.036 NTU), pH (6.87), Dureza Total CaCO_3 (201.4 mg/L), Calcio Ca^(++) (12.67mg/L), Sólidos Totales (420.0mg/L), Alcalinidad (50.01mg/L), Cloruro Cl^- (123.40 mg/L), Sulfatos SO=4 (49.90 mg/L), Hierro (0.041 mg/L), Manganeso (0.038 mg/L), todo estos resultados cumplen con los límites máximos permisibles para la calidad de agua que el Ministerio de Salud exige. Por lo tanto se concluye que es factible utilizar filtros cerámicos, conformados por jipi de quinua (Chenopodium quinoa Willd.) y arcilla e impregnados con plata coloidal, para el proceso de tratamiento del agua cruda de pozo, convirtiéndolo en apto para consumo y uso en procesos agroindustriales

Data from: Evidence for an association between post-fledging dispersal and microsatellite multilocus heterozygosity in a large population of greater flamingos

Dispersal can be divided into three stages: departure, transience and settlement. Despite the fact that theoretical studies have emphasized the importance of heterozygosity on dispersal strategies, empirical evidence of its effect on different stages of dispersal is lacking. Here, using multi-event capture-mark-recapture models, we show a negative association between microsatellite multilocus heterozygosity (MLH; 10 loci; n = 1023) and post-fledging dispersal propensity for greater flamingos, Phoenicopterus roseus, born in southern France. We propose that the negative effects of inbreeding depression affects competitive ability and therefore more homozygous individuals are more likely to disperse because they are less able to compete within the highly saturated natal site. Finally, a model with the effect of MLH on propensity of post-fledgling dispersers to disperse to the long-distance sites of Africa was equivalent to the null model, suggesting that MLH had low to no effect on dispersal distance. Variations in individual genetic quality thus result in context-dependent heterogeneity in dispersal strategies at each stage of dispersal. Our results have important implications on fitness since sites visited early in life are known to influence site selection later on in life and future survival