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Daniel W. Tripp Tonie E. Rocke Jonathan P. Runge Rachel C. Abbott Michael W. Miller 《EcoHealth》2017,14(3):451-462
Plague impacts prairie dogs (Cynomys spp.), the endangered black-footed ferret (Mustela nigripes) and other sensitive wildlife species. We compared efficacy of prophylactic treatments (burrow dusting with deltamethrin or oral vaccination with recombinant “sylvatic plague vaccine” [RCN-F1/V307]) to placebo treatment in black-tailed prairie dog (C. ludovicianus) colonies. Between 2013 and 2015, we measured prairie dog apparent survival, burrow activity and flea abundance on triplicate plots (“blocks”) receiving dust, vaccine or placebo treatment. Epizootic plague affected all three blocks but emerged asynchronously. Dust plots had fewer fleas per burrow (P < 0.0001), and prairie dogs captured on dust plots had fewer fleas (P < 0.0001) than those on vaccine or placebo plots. Burrow activity and prairie dog density declined sharply in placebo plots when epizootic plague emerged. Patterns in corresponding dust and vaccine plots were less consistent and appeared strongly influenced by timing of treatment applications relative to plague emergence. Deltamethrin or oral vaccination enhanced apparent survival within two blocks. Applying insecticide or vaccine prior to epizootic emergence blunted effects of plague on prairie dog survival and abundance, thereby preventing colony collapse. Successful plague mitigation will likely entail strategic combined uses of burrow dusting and oral vaccination within large colonies or colony complexes. 相似文献
3.
Jonathan H. Clarke Judith I. Laurie Harry J. Gilbert Geoffrey P. Hazlewood 《FEMS microbiology letters》1991,83(3):305-309
Cellulomonas fimi genomic DNA encoding xylanase activity has been cloned and expressed in Escherichia coli. As judged by DNA hybridization and restriction analysis, twelve xylanase-positive clones carried a minimum of four different xylanase (xyn) genes. The encoded enzymes were devoid of cellulase activity but three of the four bound to Avicel. 相似文献
4.
Most Serratia marcescens strains produce a new type of cytolysin (hemolysin) which is also found in other Serratia species. The hemolytic polypeptide ShlA (M(r) 162 101) is secreted across the outer membrane through the help of the ShlB protein which also involves conversion of an inactive precursor in an hemolytically active form. Both proteins are synthesized with signal sequences which are released during export across the cytoplasmic membrane. Mutants expressing inactive ShlB derivatives are impaired in activation and secretion suggesting a tight coupling between both processes. The region of ShlA for activation and secretion is confined to the N-terminal 16% of the polypeptide which contains the sequence NPNG which is also found in the Proteus hemolysin, the Bordetella pertussis filamentous hemagglutinin and two highly expressed outer membrane proteins of Haemophilus influenzae. Substitution of the first asparagine (N) residue by isoleucine converts the Serratia hemolysin into an inactive secretion incompetent form. It is concluded that this region is recognized by ShlB for activation and secretion of ShlA. The Serratia hemolysin forms defined pores in erythrocyte membranes. 相似文献
5.
Emmanuel Serrano Russell Alpizar-Jara Nicolas Morellet Aidan Jonathan Mark Hewison 《European Journal of Wildlife Research》2008,54(4):675-680
From a literature review of five wildlife ecology journals since 1937, we document how using indices to monitor ungulate body
condition is common practice, with the kidney fat index (KFI = weight of fat around the kidneys/weight of kidneys without
fat × 100) as the favoured tool (82% of studies). In this context, we highlight the problems of using indices when underlying
statistical assumptions are not met (isometry, parallel slopes between treatments). We show, with real and simulated data
for two cervids with contrasting fat storage strategies, how results from analysis of variance of KFI values differ from analysis
of covariance (ANCOVA) of raw data. We conclude that the KFI is affected by the restrictions typically associated with derived
index values, and as a consequence, statistical analysis of the KFI could generate spurious results leading to erroneous interpretations
concerning variation in body condition of ungulate populations. Thus, we recommend analysing fat weight as an untransformed
variable in ANCOVA (kidney weight as covariate) to describe body condition variation in ungulates.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
6.
Jonathan Marks 《Evolutionary anthropology》2017,26(4):184-188
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Susan Morrison Grace John-Stewart John J. Egessa Sezi Mubezi Sylvia Kusemererwa Dennis K. Bii Nulu Bulya Francis Mugume James D. Campbell Jonathan Wangisi Elizabeth A. Bukusi Connie Celum Jared M. Baeten Partners PrEP Study Team 《PloS one》2015,10(10)
During an HIV-1 prevention clinical trial in East Africa, we observed 16 cases of primary HIV-1 infection in women coincident with pregnancy or breastfeeding. Nine of eleven pregnant women initiated rapid combination antiretroviral therapy (ART), despite having CD4 counts exceeding national criteria for ART initiation; breastfeeding women initiated ART or replacement feeding. Rapid ART initiation during primary HIV-1 infection during pregnancy and breastfeeding is feasible in this setting. 相似文献
9.
Effect of domestic cattle stocking on the nutritional condition of white-tailed deerOdocoileus virginianus (Zimmermann, 1780) was assessed using physiological indices of collected specimens. Three study areas were delineated in McCurtain County, Oklahoma (heavy cattle stocking), and Howard (moderate to light cattle stocking) and Pike (no cattle stocking) counties, Arkansas that were similar with respect to soils and vegetation but differed with respect to cattle stocking rate. Female white-tailed deer were collected from study areas in February and August 1987–1988 to assess nutritional condition. Deer collected from study areas exposed to cattle grazing in February had lower carcass weights, fat attributes (femur marrow and kidney fat), and reproductive rates (fetuses/doe) than deer that were not exposed to cattle grazing. In August, deer collected from the moderate cattle area had heavier eviscerated carcass weights, serum glucose, albumin, and albumin/globulin ratios than deer collected from the heavy cattle area. Results suggest that if cattle are removed from managed forests in winter, nutritional condition of deer would be improved because of reduced competition for food. 相似文献
10.
A unified framework to model the potential and realized distributions of invasive species within the invaded range 下载免费PDF全文
Tarek Hattab Carol X. Garzón‐López Michael Ewald Sandra Skowronek Raf Aerts Hélène Horen Boris Brasseur Emilie Gallet‐Moron Fabien Spicher Guillaume Decocq Hannes Feilhauer Olivier Honnay Pieter Kempeneers Sebastian Schmidtlein Ben Somers Ruben Van De Kerchove Duccio Rocchini Jonathan Lenoir 《Diversity & distributions》2017,23(7):806-819