Herpetofauna of Mormon Island Preserve Hall County, Nebraska

Introduction: Studies of reptiles and amphibians in the grasslands of North America have primarily concerned the compilation of state faunal lists (e.g. Smith 1956, Hudson 1942, Webb 1970, Wheeler and Wheeler 1966). There have been a large number of reports on range extensions to augment this basic data. With the exception of the extensive studies by Fitch (1954, 1956, 1958, 1960, 1963) primarily on reptiles and Bragg (1940a, 1940b, 1943, 1953) primarily on anurans, the ecology of the herpetiles of the grasslands are not well studied. Lynch (1978) provided an excellent analysis of the ecological distributions of the leopard frogs in Nebraska. Werth (1972) presented preliminary observations on the competition of lizards. Other recent studies have concerned the ecology of herpetiles of specific sites (Platt 1973, 1975, Ballinger et al. 1979, Jones and Droge 1980). Our future understmding of the ecology of the prairie will depend largely on detailed studies of these and comparably preserved sites because of the extensive fragmentation of the central grasslands by agricultural practices. The purposes of the present study were to determine the herpetofaunal composition of a newly. created nature preserve in south central Nebraska, and to outline the general natural history of the species present. Summary: A total of ten herpetiles were reported for the Mormon Island Preserve. Each of the ten species occurring on the preserve is associated at least to some degree with aquatic habitats or riparian woodlands. The grazing and agricultural practices currently carried out at Mormon Island have apparently restricted the herpetofauna to those habitats. Herpetiles requiring large, permanent bodies of water and those burrowing species which prefer areas characterized by low water tables as well as highly terrestrial herpetiles are conspicuously absent from the Mormon Island Preserve

Preservation of RNA and DNA from mammal samples under field conditions

Ecological and conservation genetics require sampling of organisms in the wild. Appropriate preservation of the collected samples, usually by cryostorage, is key to the quality of the genetic data obtained. Nevertheless, cryopreservation in the field to ensure RNA and DNA stability is not always possible. We compared several nucleic acid preservation solutions appropriate for field sampling and tested them on rat (Rattus rattus) blood, ear and tail tip, liver, brain and muscle. We compared the efficacy of a nucleic acid preservation (NAP) buffer for DNA preservation against 95% ethanol and Longmire buffer, and for RNA preservation against RNAlater (Qiagen) and Longmire buffer, under simulated field conditions. For DNA, the NAP buffer was slightly better than cryopreservation or 95% ethanol, but high molecular weight DNA was preserved in all conditions. The NAP buffer preserved RNA as well as RNAlater. Liver yielded the best RNA and DNA quantity and quality; thus, liver should be the tissue preferentially collected from euthanized animals. We also show that DNA persists in nonpreserved muscle tissue for at least 1 week at ambient temperature, although degradation is noticeable in a matter of hours. When cryopreservation is not possible, the NAP buffer is an economical alternative for RNA preservation at ambient temperature for at least 2 months and DNA preservation for at least 10 months. © 2013 John Wiley & Sons Ltd.Peer Reviewe

Host genetics and diet, but not immunoglobulin A expression, converge to shape compositional features of the gut microbiome in an advanced intercross population of mice

Background: Individuality in the species composition of the vertebrate gut microbiota is driven by a combination of host and environmental factors that have largely been studied independently. We studied the convergence of these factors in a G10 mouse population generated from a cross between two strains to search for quantitative trait loci (QTLs) that affect gut microbiota composition or ileal Immunoglobulin A (IgA) expression in mice fed normal or high-fat diets. Results: We found 42 microbiota-specific QTLs in 27 different genomic regions that affect the relative abundances of 39 taxa, including four QTL that were shared between this G10 population and the population previously studied at G4. Several of the G10 QTLs show apparent pleiotropy. Eight of these QTLs, including four at the same site on chromosome 9, show significant interaction with diet, implying that diet can modify the effects of some host loci on gut microbiome composition. Utilization patterns of IghV variable regions among IgA-specific mRNAs from ileal tissue are affected by 54 significant QTLs, most of which map to a segment of chromosome 12 spanning the Igh locus. Despite the effect of genetic variation on IghV utilization, we are unable to detect overlapping microbiota and IgA QTLs and there is no significant correlation between IgA variable pattern utilization and the abundance of any of the taxa from the fecal microbiota. Conclusions: We conclude that host genetics and diet can converge to shape the gut microbiota, but host genetic effects are not manifested through differences in IgA production