The Experts below are selected from a list of 249 Experts worldwide ranked by ideXlab platform

Simon C Griffith - One of the best experts on this subject based on the ideXlab platform.

Henrik Jeldtoft Jensen - One of the best experts on this subject based on the ideXlab platform.

Gabriele Sorci - One of the best experts on this subject based on the ideXlab platform.

  • new polymorphic microsatellite loci in the house sparrow Passer Domesticus
    Molecular Ecology Resources, 2009
    Co-Authors: Stephane Garnier, Patrick Durand, Celine Arnathau, Angemarie Risterucci, R Esparzasalas, Elise Cellierholzem, Gabriele Sorci
    Abstract:

    We developed 13 new polymorphic microsatellite loci in the house sparrow (Passer Domesticus), which exhibited from 2 to 15 alleles. Observed and expected heterozygosities ranged from 0.17 to 0.77 and from 0.35 to 0.85, respectively. We detected no linkage disequilibrium between loci. Allele frequencies supported Hardy-Weinberg equilibrium for 8 loci out of 13 after Bonferroni correction. Combined with loci previously isolated in the house sparrow, these new microsatellite markers provide valuable tools to study population genetics of this species. (Resume d'auteur)

  • PERMANENT GENETIC RESOURCES NOTE New polymorphic microsatellite loci in the house sparrow, Passer Domesticus
    2009
    Co-Authors: Stephane Garnier, Patrick Durand, Celine Arnathau, Gabriele Sorci, R. Esparza-salas, Boulevard Gabriel
    Abstract:

    We developed 13 new polymorphic microsatellite loci in the house sparrow (Passer Domesticus), which exhibited from 2 to 15 alleles. Observed and expected heterozygosities ranged from 0.17 to 0.77 and from 0.35 to 0.85, respectively. We detected no linkage disequilibrium between loci. Allele frequencies supported Hardy–Weinberg equilibrium for 8 loci out of 13 after Bonferroni correction. Combined with loci previously isolated in the house sparrow, these new microsatellite markers provide valuable tools to study population genetics of this species.

  • testosterone and sexual signalling in male house sparrows Passer Domesticus
    Behavioral Ecology and Sociobiology, 2001
    Co-Authors: Guillermo Gonzalez, Gabriele Sorci, Linda C Smith, Florentino De Lope
    Abstract:

    Female preference for mates with elaborated ornaments has often been explained on the basis that exaggerated secondary sexual traits might reflect individual quality and females might gather direct and indirect benefits in mating with such males. Sexual signals must however also entail costs to be reliable indicators of male quality. Androgens have been suggested as a physiological link between sexual signals and individual quality for several reasons, including their immunosuppressive effect. In this study, we tested two hypotheses linked to the hormonal basis of sexual signal expression. First, we investigated whether testosterone is correlated with the size of the black feather bib on the throat of male house sparrows (Passer Domesticus) – a trait involved in intra- and inter-sexual selection. Second, we tested whether testosterone affects the seasonal exposure of the trait. Observational work conducted in 1998 showed that the testosterone level was positively correlated with badge size both in spring and in the subsequent fall, after molt. In 1999, we experimentally reduced spring testosterone levels using silastic implants filled with cyproterone acetate, an antiandrogen. Male house sparrows implanted with cyproterone acetate showed reduced exposure of the badge, because the white tips of the black feathers of the badge wore off later than in control males implanted with empty silastic tubes. This result suggests that testosterone can be causally involved in the expression of a secondary sexual trait in house sparrows, at least in terms of its seasonal exposure.

Richard A Bowen - One of the best experts on this subject based on the ideXlab platform.

  • persistent west nile virus infection in the house sparrow Passer Domesticus
    Archives of Virology, 2009
    Co-Authors: Nicole M Nemeth, Ginger Young, Christina Ndaluka, Helle Bielefeldtohmann, Nicholas Komar, Richard A Bowen
    Abstract:

    Long-term persistence of West Nile virus (WNV) infection within vertebrate reservoir hosts is a potential mechanism for overwintering of this (and other) arbovirus(es) at temperate latitudes. The house sparrow (Passer Domesticus), an established amplifying host for WNV and other arboviruses, was used as a model to confirm chronicity of WNV infection in Passerine birds and to evaluate the feasibility of two overwintering mechanisms: blood-borne infection of arthropod vectors (recrudescence) and oral infection of vertebrate reservoir hosts (ingestion of infected tissues through predation). WNV-inoculated sparrows were monitored for persistent infection for up to 2 years. Infectious virus persisted in tissues through 43 days, but not in sera beyond 6 days. Viral RNA persisted in tissues through 65 days. Chronicity of WNV infection in some tissues, but not blood, supports the predation mechanism of WNV overwintering, but not recrudescence. RNA persistence impacts interpretation and etiologic determination of avian mortality.

  • variation in virulence of west nile virus strains for house sparrows Passer Domesticus
    American Journal of Tropical Medicine and Hygiene, 2005
    Co-Authors: Stanley A Langevin, Richard A Bowen, Aaron C Brault, Nicholas A Panella, Nicholas Komar
    Abstract:

    The observation of avian mortality associated with West Nile virus (WNV) infection has become a hallmark epidemiologic feature in the recent emergence of this pathogen in Israel and North America. To determine if phenotypic differences exist among different WNV isolates, we exposed house sparrows (Passer Domesticus) to low passage, lineage 1 WNV strains from North America (NY99), Kenya (KEN), and Australia (KUN; also known as Kunjin virus). House sparrows inoculated with the NY99 and KEN strains experienced similar mortality rates and viremia profiles. The KUN strain elicited significantly lower-titered viremia when compared with the other strains and induced no mortality. This study suggests that natural mortality in house sparrows due to Old World strains of WNV may be occurring where the KEN strain occurs.

Terry Burke - One of the best experts on this subject based on the ideXlab platform.