Characterizing historical and modern fire regimes in Michigan (USA): A landscape ecosystem approach   总被引：4，自引：0，他引：4  

Cleland  David T.  Crow  Thomas R.  Saunders  Sari C.  Dickmann  Donald I.  Maclean  Ann L.  Jordan  James K.  Watson  Richard L.  Sloan  Alyssa M.  Brosofske  Kimberley D. 《Landscape Ecology》2004,19(3):311-325

We studied the relationships of landscape ecosystems to historical and contemporary fire regimes across 4.3 million hectares in northern lower Michigan (USA). Changes in fire regimes were documented by comparing historical fire rotations in different landscape ecosystems to those occurring between 1985 and 2000. Previously published data and a synthesis of the literature were used to identify six forest-replacement fire regime categories with fire rotations ranging from very short (<100 years) to very long (>1,000 years). We derived spatially-explicit estimates of the susceptibility of landscape ecosystems to fire disturbance using Landtype Association maps as initial units of investigation. Each Landtype Association polygon was assigned to a fire regime category based on associations of ecological factors known to influence fire regimes. Spatial statistics were used to interpolate fire points recorded by the General Land Office. Historical fire rotations were determined by calculating the area burned for each category of fire regime and dividing this area by fifteen (years) to estimate area burned per annum. Modern fire rotations were estimated using data on fire location and size obtained from federal and state agencies. Landtype Associations networked into fire regime categories exhibited differences in both historical and modern fire rotations. Historical rotations varied by 23-fold across all fire rotation categories, and modern forest fire rotations by 13-fold. Modern fire rotations were an order of magnitude longer than historical rotations. The magnitude of these changes has important implications for forest health and understanding of ecological processes in most of the fire rotation categories that we identified.This revised version was published online in May 2005 with corrections to the Cover Date.  相似文献   

Validation of the specificity and sensitivity of species-specific primers that provide a reliable molecular diagnostic for <Emphasis Type="Italic">Xiphinema diversicaudatum</Emphasis>, <Emphasis Type="Italic">X. index</Emphasis> and <Emphasis Type="Italic">X. vuittenezi</Emphasis>     

Judith Hübschen  Lilo Kling  Ulrike Ipach  Volker Zinkernagel  Nathalie Bosselut  Daniel Esmenjaud  Derek J.F. Brown  Roy Neilson 《European journal of plant pathology / European Foundation for Plant Pathology》2004,110(8):779-788

Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry.  相似文献   

Diagnosis of Congenital Cardiac Right-to-left Shunts with ^99mTc-macroaggregated Albumin     

Federica Morandi  DVM  MS    Gregory B. Daniel  DVM  MS    Rebecca E. Gompf  DVM  MS    Anne Bahr  DVM  MS 《Veterinary radiology & ultrasound》2004,45(2):97-102

Diagnosing right-to-left congenital cardiac shunts can be difficult. Cardiac catheterization and angiocardiography represent the traditional gold standard for diagnosis, but they are invasive. Nuclear scintigraphy using 99mTc-macroaggregated albumin (MAA) has been employed in humans as an alternate method of diagnosis. This study reviews eight dogs presented for evaluation of a suspect right-to-left cardiac shunt that were examined using 99mTc-MAA. In all, 2-4 mCi (74-148 MBq) of reduced particle 99mTc-MAA were injected IV in a cephalic vein and static images of the whole body, including right and left lateral, dorsal, and ventral views, were acquired for 60 s and stored into a 256 x 256 x 16 matrix. Shunt fractions were calculated. One dog with radiopharmaceutical distribution limited to the lungs did not have a shunt. Seven dogs had distribution of the radiopharmaceutical outside the pulmonary capillary bed, indicating bypassing of the pulmonary capillary circulation due to a right-to-left shunt. Four dogs had 99mTc-MAA within the brain. Three dogs that did not have brain uptake, but instead had a sharp cutoff of radioactivity at the level of the front limbs and neck, were diagnosed with reverse patent ductus arteriosus (PDA). The asymmetric distribution of the radiopharmaceutical is due to the location of the shunt, distal to the brachiocephalic trunk and left subclavian artery. Shunt fractions of dogs with extrapulmonary radioactivity ranged from 40% to 59%. Nuclear scintigraphy with 99mTc-MAA is a quick alternative method of diagnosing right-to-left cardiac shunts that permits quantification of shunt fraction. Distinguishing between reverse PDA and other right-to-left shunts may be possible based on the radiopharmaceutical distribution.  相似文献   

Manipulation of Ovarian Function for the Reproductive Management of Dairy Cows     

Thatcher  W.W.  Bartolome  J.A.  Sozzi  A.  Silvestre  F.  Santos  J.E.P. 《Veterinary research communications》2004,28(1):111-119

Veterinary Research Communications -  相似文献   

Kinematic discrimination of ataxia in horses is facilitated by blindfolding          下载免费PDF全文

E. Olsen  N. FouchÉ  H. Jordan  T. Pfau  R. J. Piercy 《Equine veterinary journal》2018,50(2):166-171

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Fecal microbiota transplantation in puppies with canine parvovirus infection          下载免费PDF全文

Giorgio Q. Pereira  Lucas A. Gomes  Iago S. Santos  Alice F. Alfieri  J. S. Weese  Marcio C. Costa 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(2):707-711

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Caprine toxoplasmosis in Southern Brazil: a comparative seroepidemiological study between the indirect immunofluorescence assay,the enzyme-linked immunosorbent assay,and the modified agglutination test     

Fortes  Maira Salomão  Lopes-Mori  Fabiana Maria Ruiz  Caldart  Eloiza Teles  Constantino  Caroline  Evers  Fernanda  Pagliari  Sthefany  de Almeida  Jonatas Campos  Barros  Luiz Daniel  Freire  Roberta Lemos  Garcia  João Luis  Headley  Selwyn Arlington  Navarro  Italmar Teodorico 《Tropical animal health and production》2018,50(2):413-419

Tropical Animal Health and Production - This study investigated the prevalence of caprine toxoplasmosis in goat herds from Southern Brazil by the indirect immunofluorescence assay (IFA), and...  相似文献   

Genomic characterization of the first oral avian papillomavirus in a colony of breeding canaries (<Emphasis Type="Italic">Serinus canaria</Emphasis>)     

Daniel A. Truchado  Michaël A. J. Moens  Sergio Callejas  Javier Pérez-Tris  Laura Benítez 《Veterinary research communications》2018,42(2):111-120

Papillomaviruses are non-enveloped, DNA viruses that infect skin and mucosa of a wide variety of vertebrates, causing neoplasias or simply persisting asymptomatically. Avian papillomaviruses, with six fully sequenced genomes, are the second most studied group after mammalian papillomaviruses. In this study, we describe the first oral avian papillomavirus, detected in the tongue of a dead Yorkshire canary (Serinus canaria) and in oral swabs of the same bird and other two live canaries from an aviary in Madrid, Spain. Its genome is 8,071 bp and presents the canonical papillomavirus architecture with six early (E6, E7, E1, E9, E2, E4) and two late open reading frames (L1 and L2) and a long control region between L1 and E6. This new avian papillomavirus L1 gene shares a 64% pairwise identity with FcPV1 L1, so it has been classified as a new species (ScPV1) within the Ethapapillomavirus genus. Although the canary died after showing breathing problems, there is no evidence that the papillomavirus caused those symptoms so it could be part of the oral microbiota of the birds. Hence, future investigations are needed to evaluate the clinical relevance of the virus.  相似文献   

Laryngeal mask airway and transient hypercapnic hyperpnea for video‐endoscopic assessment of unilateral laryngeal paralysis in dogs          下载免费PDF全文

Daniel M. Sakai MV  DACVAA  Manuel Martin‐Flores MV  DACVAA  Amanda K. Jones PhD  Galina M. Hayes BVSc  PhD  DACVECC  DACVS‐SA  Marina J. McConkey DVM  DACVS‐SA  Jonathan Cheetham VetMB  PhD  DACVS‐LA 《Veterinary surgery : VS》2018,47(4):543-548

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Protocol changes to reduce implant‐associated infection rate after tibial plateau leveling osteotomy: 703 dogs, 811 TPLO (2006‐2014)          下载免费PDF全文

Samantha L. Stine DVM  Susan M. Odum PhD  W. Daniel Mertens DVM  Diplomate ACVS 《Veterinary surgery : VS》2018,47(4):481-489

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