Metaphase I orientation of Robertsonian trivalents in the water-hyacinth grasshopper, Cornops aquaticum (Acrididae, Orthoptera)

Trivalents resulting from polymorphic Robertsonian rearrangements must have a regular orientation in metaphase I if the polymorphisms are to be maintained. It has been argued that redistribution of proximal and interstitial chiasmata to more distal positions is necessary for a convergent orientation, the only one that produces viable gametes. Cornops aquaticum is a South-American grasshopper that lives and feeds on water-hyacinths, and has three polymorphic Robertsonian rearrangements in its southernmost distribution area in Central Argentina and Uruguay. The orientation of trivalents in metaphase I, the formation of abnormal spermatids and the frequency and position of chiasmata in the trivalents, was analysed in a polymorphic population of C. aquaticus. In this study we observed a correlation between the number of trivalents with the frequency of abnormal spermatids; additionally, the number of chiasmata, especially proximal and interstitial ones, was strongly correlated with the frequency of the linear orientation. Therefore we confirmed our previous assumption, based on other evidence, that the chiasmata redistribution in fusion carriers is essential to the maintenance of the polymorphisms

PLAN DE ACCIÓN PARA LA CONSERVACIÓN DEL AGUARÁ GUAZÚ EN SANTA FE VERSIÓN 01 PERÍODO 2009 – 2014

El presente plan fue realizado usando de base los capítulos 1, 2, 3 y 4 del trabajo: Estado  de  conocimiento  y  conservación  del  aguará  guazú  (Chrysocyon  brachyurus)  en  la  provincia  de Santa Fe, Argentina. . Se tomó como base orientaciones generales de Margoluis y Salafsky (1998) y en la estructura general se siguió de modelo práctico a Jiménez Pérez (2006). Para asignar la prioridad se utilizaron las categorías desarrolladas por el Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais Renováveis (Baz Hughes, et al. 2006), estas son: Esencial: una actividad específica cuyo cumplimiento es necesario para evitar una declinación de las poblaciones que pueda llevar a la extinción de la especie en la naturaleza y/o en cautiverio. Alta: una actividad específica cuyo cumplimiento es necesario para evitar una declinación poblacional de más del 20% de una población en 20 años o menos. Media: una actividad específica cuyo cumplimiento es necesario para evitar una declinación poblacional de hasta el 20% de una población en 20 años o menos. Baja: una actividad específica cuyo cumplimiento es necesario para prevenir declinaciones poblacionales  locales o que se estima que dicha acción apenas tiene un pequeño impacto sobre las poblaciones en un área grande. Se trata de una planificación para cinco años pues la experiencia indica que a Santa Fe le falta mucho  trabajo  y experiencia para  fortalecer  su  forma de  ver  y de actuar en  la  recuperación de  las especies amenazadas.  Por ejemplo muchas de  las amenazas  indirectas (generadoras de amenazas directas) que afectan a esta especie son producto de  la  falta de coordinación, compromiso, metas y objetivos comunes entre  los profesionales de  la conservación, sea sociedad civil u organismos estatales. Es así como se pretende en un corto plazo y monitoreando constantemente, las acciones y sus resultados, lograr un plan a futuro de mediano y largo plazo.Fil: Biassati, R. Secreataría de Medio Ambiente de Santa Fe; ArgentinaFil: Larriera, Alejandro. Secretaría de Medio Ambiente de Santa Fe; ArgentinaFil: Mosso, E.. Secretaría de Medio Ambiente de Santa Fe; ArgentinaFil: Rozztti, J.C.. Secretaría de Medio Ambiente de Santa Fe; ArgentinaFil: Moggia, L.. Secretaría de Medio Ambiente, Santa Fe; ArgentinaFil: Pautasso, A.. Museo de Cs Naturales Florentino Ameghino; ArgentinaFil: Nebozuk, M. A.. Museo Provincial de Ciencias Naturales Ángel Gallardo; ArgentinaFil: Walker, C.. Universidad Nacional del Litoral; ArgentinaFil: Ramirez, C.. Universidad Nacional del Litoral; ArgentinaFil: Mirol, P.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Raimondi, Vanina Belén. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales "Bernardino Rivadavia"; ArgentinaFil: Beldomenico, Pablo Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina. Laboratorio de Ecología de Enfermedades; ArgentinaFil: Eberhardt, María Ayelen Teresita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina. Laboratorio de Ecología de Enfermedades; ArgentinaFil: Manzzoli, D.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - CONICET - Santa Fe. Instituto de Ciencias Veterinarias del Litoral; Argentina. Laboratorio de Ecología de Enfermedades; ArgentinaFil: Correa, A.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Terragona, E.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Magni, C.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Alvarado, S.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; ArgentinaFil: Barengo, E.. Universidad Nacional del Litoral. Facultad de Ciencias Veterinarias; Argentin

Cold adaptation drives population genomic divergence in the ecological specialist, Drosophila montana

Funding: UK Natural Environment Research Council (Grant Number(s): NE/L501852/1, NE/P000592/1); Academy of Finland (GrantNumber(s): 267244, 268214, 322980), Ella ja Georg Ehrnroothin Säätiö.Detecting signatures of ecological adaptation in comparative genomics is challenging, but analysing population samples with characterised geographic distributions, such as clinal variation, can help identify genes showing covariation with important ecological variation. Here, we analysed patterns of geographic variation in the cold-adapted species Drosophila montana across phenotypes, genotypes and environmental conditions and tested for signatures of cold adaptation in population genomic divergence. We first derived the climatic variables associated with the geographic distribution of 24 populations across two continents to trace the scale of environmental variation experienced by the species, and measured variation in the cold tolerance of the flies of six populations from different geographic contexts. We then performed pooled whole genome sequencing of these six populations, and used Bayesian methods to identify SNPs where genetic differentiation is associated with both climatic variables and the population phenotypic measurements, while controlling for effects of demography and population structure. The top candidate SNPs were enriched on the X and fourth chromosomes, and they also lay near genes implicated in other studies of cold tolerance and population divergence in this species and its close relatives. We conclude that ecological adaptation has contributed to the divergence of D. montana populations throughout the genome and in particular on the X and fourth chromosomes, which also showed highest interpopulation FST. This study demonstrates that ecological selection can drive genomic divergence at different scales, from candidate genes to chromosome-wide effects.Publisher PDFPeer reviewe

Lymnaea schirazensis, an Overlooked Snail Distorting Fascioliasis Data: Genotype, Phenotype, Ecology, Worldwide Spread, Susceptibility, Applicability

BACKGROUND: Lymnaeid snails transmit medical and veterinary important trematodiases, mainly fascioliasis. Vector specificity of fasciolid parasites defines disease distribution and characteristics. Different lymnaeid species appear linked to different transmission and epidemiological patterns. Pronounced susceptibility differences to absolute resistance have been described among lymnaeid populations. When assessing disease characteristics in different endemic areas, unexpected results were obtained in studies on lymnaeid susceptibility to Fasciola. We undertook studies to understand this disease transmission heterogeneity. METHODOLOGY/PRINCIPAL FINDINGS: A ten-year study in Iran, Egypt, Spain, the Dominican Republic, Mexico, Venezuela, Ecuador and Peru, demonstrated that such heterogeneity is not due to susceptibility differences, but to a hitherto overlooked cryptic species, Lymnaea schirazensis, confused with the main vector Galba truncatula and/or other Galba/Fossaria vectors. Nuclear rDNA and mtDNA sequences and phylogenetic reconstruction highlighted an old evolutionary divergence from other Galba/Fossaria species, and a low intraspecific variability suggesting a recent spread from one geographical source. Morphometry, anatomy and egg cluster analyses allowed for phenotypic differentiation. Selfing, egg laying, and habitat characteristics indicated a migration capacity by passive transport. Studies showed that it is not a vector species (n = 8572 field collected, 20 populations): snail finding and penetration by F. hepatica miracidium occur but never lead to cercarial production (n = 338 experimentally infected). CONCLUSIONS/SIGNIFICANCE: This species has been distorting fasciolid specificity/susceptibility and fascioliasis geographical distribution data. Hence, a large body of literature on G. truncatula should be revised. Its existence has henceforth to be considered in research. Genetic data on livestock, archeology and history along the 10,000-year post-domestication period explain its wide spread from the Neolithic Fertile Crescent. It is an efficient biomarker for the follow-up of livestock movements, a crucial aspect in fascioliasis emergence. It offers an outstanding laboratory model for genetic studies on susceptibility/resistance in F. hepatica/lymnaeid interaction, a field of applied research with disease control perspectives

Mitochondrial variability in the D-loop of four equine breeds shown by PCR-SSCP analysis

A fragment of 466 base pairs from a highly variable peripheral region of the mitochondrial D-loop of horses was amplified and analyzed by single stranded conformational polymorphism (SSCP). Fourteen distinct SSCP variants were detected in 100 horses belonging to four breeds (Arabian, ARB; Thoroughbred, TB; Argentinian Creole, ARC; and Peruvian Paso from Argentina, PPA). Each breed showed four to eight SSCP variants, many of which were shared between two or three of the studied breeds. Arabian horses were the most variable (eigth variants), with three variants unique to the breed. PPA and ARC showed two and one characteristic SSCP variants, respectively, while TB shared all its variants with at least one of the other breeds. An analysis based on the presence/absence of the variants revealed a closer relationship between PPA and TB, which was not completely unexpected considering the mixed ancestry of the PPA mares. The results also confirm the efficiency of SSCP to detect variability in horse mitochondrial DNA

Mitochondrial variability in the D-loop of four equine breeds shown by PCR-SSCP analysis

Abstract A fragment of 466 base pairs from a highly variable peripheral region of the mitochondrial D-loop of horses was amplified and analyzed by single stranded conformational polymorphism (SSCP). Fourteen distinct SSCP variants were detected in 100 horses belonging to four breeds (Arabian, ARB; Thoroughbred, TB; Argentinian Creole, ARC; and Peruvian Paso from Argentina, PPA). Each breed showed four to eight SSCP variants, many of which were shared between two or three of the studied breeds. Arabian horses were the most variable (eigth variants), with three variants unique to the breed. PPA and ARC showed two and one characteristic SSCP variants, respectively, while TB shared all its variants with at least one of the other breeds. An analysis based on the presence/absence of the variants revealed a closer relationship between PPA and TB, which was not completely unexpected considering the mixed ancestry of the PPA mares. The results also confirm the efficiency of SSCP to detect variability in horse mitochondrial DNA