Veterinarians and public practice at the Virginia-Maryland Regional College of Veterinary Medicine: building on a tradition of expertise and partnership     

Feldman KA  Walters BK 《Journal of veterinary medical education》2008,35(2):225-230

The Virginia-Maryland Regional College of Veterinary Medicine (VMRCVM), a regional veterinary college for Maryland and Virginia, has a long and unique tradition of encouraging careers in public and corporate veterinary medicine. The VMRCVM is home to the Center for Public and Corporate Veterinary Medicine (CPCVM), and each year approximately 10% of the veterinary students choose the public/corporate veterinary medicine track. The faculty of the CPCVM, and their many partners from the veterinary public practice community, teach in the veterinary curriculum and provide opportunities for students locally, nationally, and internationally during summers and the final clinical year. Graduates of the program work for government organizations, including the US Department of Agriculture, the Food and Drug Administration, and the Centers for Disease Control and Prevention, as well as in research, in industry, and for non-governmental organizations. Recent activities include securing opportunities for students, providing career counseling for graduate veterinarians interested in making a career transition, delivering continuing education, and offering a preparatory course for veterinarians sitting the board examination for the American College of Veterinary Preventive Medicine. As the VMRCVM moves forward in recognition of the changing needs of the veterinary profession, it draws on its tradition of partnership and capitalizes on the excellence of its existing program. Future plans for the CPCVM include possible expansion in the fields of public health, public policy, international veterinary medicine, organizational leadership, and the One Health initiative. Quality assurance and evaluation of the program is ongoing, with recognition that novel evaluation approaches will be useful and informative.  相似文献   

Comparative Aspects of the Endotoxin- and Cytokine-Induced Endocrine Cascade Influencing Neuroendocrine Control of Growth and Reproduction in Farm Animals     

BK Whitlock  JA Daniel  RR Wilborn  TH Elsasser  JA Carroll  JL Sartin 《Reproduction in domestic animals》2008,43(S2):317-323

Disease in animals is a well-known inhibitor of growth and reproduction. Earlier studies were initiated to determine the effects of endotoxin on pituitary hormone secretion. These studies found that in sheep, growth hormone (GH) concentration was elevated, whereas insulin-like growth factor-I (IGF-I) was inhibited, as was luteinizing hormone (LH). Examination of the site of action of endotoxin in sheep determined that somatotropes expressed the endotoxin receptor (CD14) and that both endotoxin and interleukin-Iβ activated GH secretion directly from the pituitary. In the face of elevated GH, there is a reduction of IGF-I in all species examined. As GH cannot activate IGF-I release during disease, there appears to be a downregulation of GH signalling at the liver, perhaps related to altered nitration of Janus kinase (JAK). In contrast to GH downregulation, LH release is inhibited at the level of the hypothalamus. New insights have been gained in determining the mechanisms by which disease perturbs growth and reproduction, particularly with regard to nitration of critical control pathways, with this perhaps serving as a novel mechanism central to lipopolysaccharide suppression of all signalling pathways. This pathway-based analysis is critical to the developing novel strategies to reverse the detrimental effect of disease on animal production.  相似文献   

Gene Expression of Monocarboxylate Transporters and Oocyte‐secreted Factors in Bovine Cumulus‐oocyte Complexes Selected by Brilliant Cresyl Blue          下载免费PDF全文

EF Lopes  LS Marques  RG Duranti  ATD de Oliveira  RFF Lopes  JL Rodrigues 《Reproduction in domestic animals》2015,50(5):763-770

  相似文献   

Comparing trophic position of stream fishes using stable isotope and gut contents analyses   总被引：1，自引：0，他引：1  

S. M. Rybczynski  D. M. Walters  K. M. Fritz  B. R. Johnson 《Ecology of Freshwater Fish》2008,17(2):199-206

Abstract –  Stable isotope analysis (SIA) and gut contents analysis (GCA) are commonly used in food web studies, but few studies analyse these data in concert. We used SIA (δ¹⁵N) and GCA (% composition) to identify diets and trophic position (TP) of six stream fishes and to compare TP estimates between methods. Ordination analysis of gut contents identified two primary trophic groups, omnivores and predators. Significant differences in TP_GCA and TP_SIA were similar in direction among-species and among-trophic groups; neither method detected seasonal changes in omnivore diets. Within-species TP_GCA and TP_SIA were similar except for one omnivore. TP_GCA was less variable than TP_SIA for predators, but variation between methods was similar for omnivores. While both methods were equally robust at discriminating trophic groups of fishes, TP_SIA is less laborious to estimate and may facilitate cross-stream comparisons of food web structure and energy flow.  相似文献   

Control of foliar diseases in barley: towards an integrated approach     

Dale R. Walters  Anna Avrova  Ian J. Bingham  Fiona J. Burnett  James Fountaine  Neil D. Havis  Stephen P. Hoad  Gareth Hughes  Mark Looseley  Simon J. P. Oxley  Alan Renwick  Cairistiona F. E. Topp  Adrian C. Newton 《European journal of plant pathology / European Foundation for Plant Pathology》2012,133(1):33-73

Barley is one of the world??s most important crops providing food and related products for millions of people. Diseases continue to pose a serious threat to barley production, despite the use of fungicides and resistant varieties, highlighting the impact of fungicide resistance and the breakdown of host plant resistance on the efficacy of control measures. This paper reviews progress towards an integrated approach for disease management in barley in which new methods may be combined with existing measures to improve the efficacy of control in the long-term. Advances have been made in genetic mapping of resistance (R) genes and in identifying novel sources of genes in wild barley populations and land races. Marker assisted selection techniques are being used to pyramid R genes to increase the durability of resistance. Elicitors to induce host resistance used in combination with fungicides can provide effective disease control in the field and could delay the evolution of fungicide insensitivity. Traits that may contribute to disease tolerance and escape have been identified and the extent of genetic variation within barley germplasm is being determined. Tools are being developed to integrate the above methods via an assessment of the risk of economic injury occurring from disease to guide decisions on the requirement for fungicide treatment. Barriers exist to the adoption of integrated management approaches from growers and end-users further down the supply chain (e.g. acceptance of variety mixtures) and policy incentives from government may be required for it to be taken up in practice.  相似文献   

Gas chromatographic determination of captan, folpet, and captafol residues in tomatoes, cucumbers, and apples using a wide-bore capillary column: interlaboratory study.     

D M Gilvydis  S M Walters 《Journal of the Association of Official Analytical Chemists》1991,74(5):830-835

An interlaboratory study of the determination of captan, folpet, and captafol in tomatoes, cucumbers, and apples was conducted by 4 laboratories using wide-bore capillary column gas chromatography with electron capture detection. The 3 fungicides were determined using the Luke et al. multiresidue method modified to include additional solvent elution in the optional Florisil column cleanup step used with this method. The crops were fortified with each fungicide at 3 levels per crop. Mean recoveries ranged from 86.2% for a 25.1 ppm level of captan in apples to 115.4% for a 0.288 ppm level of captafol in apples. Interlaboratory coefficients of variation ranged from 3.4% (24.7 ppm folpet) to 9.7% (0.243 ppm captafol) for tomatoes; from 2.8% (2.0 ppm captafol) to 8.2% (24.8 ppm captan) for cucumbers; and from 1.5% (0.234 ppm folpet) to 22.1% (0.266 ppm captafol) for apples.  相似文献   

Insect life history patterns. Habitat and geographic variation: Edited by Robert F. Denno and Hugh Dingle. 1981. Springer Verlag,New York,Heidelberg, Berlin. 225 pp. 24 × 15·5 cm. ISBN 0 540 90591 X. Price: DM 64·00; US$30·50     

S.M. Walters 《Biological conservation》1983,27(1):94-95

  相似文献   

Classification of octadecyl-bonded liquid chromatography columns     

M J Walters 《Journal of the Association of Official Analytical Chemists》1987,70(3):465-469

The differences in performance characteristics exhibited by columns available under the same octadecyl (C-18) label cause difficulties for the authors and users of official methods. This paper presents a simple scheme for classifying C-18 columns on the basis of the 2 predominant reverse phase retention mechanisms-hydrophobic and silanophilic interactions, which are dependent on the hydrocarbon coverage and the unreacted silanol sites, respectively. Hydrophobic interactions are represented by the ratio of anthracene k:benzene k in an acetonitrile-water (65 + 35) mobile phase. The unreacted silanols are represented by the N,N-diethyltoluamide k:anthracene k ratio with acetonitrile as the mobile phase. Column efficiency, which is largely dependent on particle size and packing technique, is included as a third classification criterion. Twelve brands of C-18 packings were subjected to this test scheme and qualitatively classified into 3 major groups on the basis of 3 criteria:hydrophobicity index, free silanol index, and efficiency. This scheme is intended as an aid in the selection of similar or equivalent columns and in defining the type of column suitable for an analytical method.  相似文献   

Residues of captan and folpet in strawberries and grapes     

D M Gilvydis  S M Walters  E S Spivak  R K Hedblad 《Journal of the Association of Official Analytical Chemists》1986,69(5):803-806

Fresh strawberries and grapes grown in Michigan and Indiana were surveyed for residues of captan and folpet, 2 fungicides commonly used on these crops. The fungicides were reportedly applied to the crops by overhead irrigation, tractor sprayer, or aerial spraying, in amounts ranging from 0.5 to 6 lb formulation/acre for captan and from 1 to 4 lb formulation/acre for folpet. Reported dates of last application ranged from just 2 days to nearly 5 months before samples were collected. Twenty-eight strawberry samples and 24 grape samples were collected of crops field-treated with one or both of these fungicides. Samples were analyzed by previously described methodology. Captan residues were found in all strawberry samples, ranging from less than 0.01 to 1.5 ppm. Folpet was found in only one strawberry sample at 0.041 ppm. Captan residues were found in only 6 grape samples, ranging from less than 0.01 to 0.082 ppm. Folpet residues were found in 12 grape samples, ranging from less than 0.01 to 0.50 ppm. All residues were well below the current tolerances of 25 ppm for both captan and folpet in strawberries and 50 ppm for captan and 25 ppm for folpet in grapes. Residue levels of these surface-applied, nonsystemic fungicides were inconsistent with amounts and dates of application, most likely because of variations in weather conditions, especially rainfall. Residues were quite stable in frozen sample homogenates, declining only 5-10% after 2 months.  相似文献   

Ion-pairing liquid chromatographic determination of benzimidazole fungicides in foods     

D M Gilvydis  S M Walters 《Journal of the Association of Official Analytical Chemists》1990,73(5):753-761

A method is described for determining residues in foods of thiabendazole, thiophanate methyl, the di-oxygen analogue metabolite [dimethyl 4,4'-O-phenylene bis (allophanate)] that is the metabolite name of the latter, and methyl-2-benzimidazole carbamate, which is the major metabolite and fungitoxic principle common to both thiophanate methyl and benomyl. The residues are extracted from the product using methanol and are partitioned into dichloromethane after initial acidification and again after subsequent alkalinization of the extract. Residues are separated and quantified by reverse-phase liquid chromatography using an ion-pairing mobile phase with UV and fluorescence detectors in tandem. Recoveries from 7 different food crops fortified at 0.2-35 ppm levels ranged from 64 to 105%.  相似文献