Temporal fine-scale genetic variation in populations of the long-tailed pygmy rice rat from Patagonia, Argentina

Factors modeling the population genetic structure are of major importance when species involved in the transmission of zoonoses are considered. The long-tailed pygmy rice rat or ‘colilargo’ Oligoryzomys longicaudatus is a highly vagile rodent species which acts as the reservoir of the Andes hantavirus in southern Argentina and Chile. To contribute to the knowledge of the processes determining the microgeographical genetic structure of populations of this species, we used 10 microsatellite loci to estimate the levels of polymorphism, individual relatedness and the population effective sizes through time and to explore if the effective size correlated with density. Individuals were sampled seasonally during a 25-month period in a population from the Argentinean Patagonia located in the endemic area of Hantavirus Pulmonary Syndrome. We detected three genetic clusters. An important temporal change in cluster prevalence was detected after a population bottleneck. Individuals of the same period presented higher mean relatedness values than between consecutive periods. Density and effective population size estimations were correlated. All analyses performed in this study are in line with the conclusion that high levels of gene flow encompassing different habitats would be a major process producing fine-scale temporal changes in the genetic composition of the studied populationFil: González Ittig, Raúl Enrique. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Diversidad y Ecologia Animal; ArgentinaFil: Polop, Francisco Jose. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Andreo, Verónica Carolina. Universidad Nacional de Rio Cuarto. Facultad de Ciencias Exactas Fisicoquimicas y Naturales; ArgentinaFil: Chiappero, Marina Beatriz. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Diversidad y Ecologia Animal; ArgentinaFil: Levis, Silvana. Direccion Nacional de Instituto de Investigacion. Adm.nacional de Laboratorio E Instituto de Salud "dr.c.g.malbran". Instituto Nacional de Enfermedades Virales Humanas; ArgentinaFil: Calderón, Gladys. Direccion Nacional de Instituto de Investigacion. Adm.nacional de Laboratorio E Instituto de Salud "dr.c.g.malbran". Instituto Nacional de Enfermedades Virales Humanas; ArgentinaFil: Provensal, Cecilia. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Polop, Jaime. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Ciencias Naturales; ArgentinaFil: Gardenal, Cristina Noemi. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Cordoba. Instituto de Diversidad y Ecologia Animal; Argentin