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1.
Abstract. Information on land resources and the capacity of land to support agricultural production is a prerequisite for the formation of sound agricultural policies. This paper summarizes Canadian experiences in developing national and regional land evaluation systems. Potential users expected the system to estimate the degree to which changes in biophysical and socio-economic conditions would alter options for land use and production, and to provide a context for more detailed analysis.
A broad-scale land evaluation system was designed to serve the needs identified by representative user groups. Two prototype systems were developed from available information to test the major features of the system design. Neither prototype was complete; one was national in extent and capable of addressing issues of national and provincial importance, the other covered a sub-provincial area but allowed for more detailed evaluation of the effects of soil modifying processes. A full range of applications was demonstrated using one or other of the prototype systems. As a result of this project, the broad-scale land evaluation system design was improved and verified, ongoing research and data collection activities were adjusted to ensure that they meet the needs of a macroscale land evaluation system, and approaches were developed to overcome problems of land evaluation system development. 相似文献
A broad-scale land evaluation system was designed to serve the needs identified by representative user groups. Two prototype systems were developed from available information to test the major features of the system design. Neither prototype was complete; one was national in extent and capable of addressing issues of national and provincial importance, the other covered a sub-provincial area but allowed for more detailed evaluation of the effects of soil modifying processes. A full range of applications was demonstrated using one or other of the prototype systems. As a result of this project, the broad-scale land evaluation system design was improved and verified, ongoing research and data collection activities were adjusted to ensure that they meet the needs of a macroscale land evaluation system, and approaches were developed to overcome problems of land evaluation system development. 相似文献
2.
Enzyme Immunoassays for the Determination of Ovine LH and FSH 总被引:2,自引:0,他引:2
GM Peclaris A Pappa K Deligiannis K Koutsotolis 《Reproduction in domestic animals》2003,38(5):367-372
The development of competitive enzyme immunoassays for ovine plasma LH (oLH) and FSH (oFSH) is described. Standards and plasma samples were preincubated with diluted antiserum to oLH or oFSH and the reacted solution (100 μl per well) was transferred to plates previously coated with oLH or oFSH, respectively. The second antibody used was anti‐rabbit IgG horseradish peroxidase. The measuring range was 0.39–50 ng/ml for each hormone and the 50% relative binding sensitivity was 9 ng/ml for oLH. The respective value for oFSH was 3.5 or 34 ng/ml with different hormone and antibody preparations used for the assay. The enzyme immunoassays were used to determine oLH and oFSH levels in plasma from ewes of two breeds during the oestrous cycle. The assays detected the first FSH surge coincident with the LH surge, the second FSH surge about 24 h later and the periodic fluctuations of FSH concentrations during the luteal phase of the oestrous cycle. These enzyme immunoassays are an efficient and economic alternative to the established radioimmunoassays (RIA) for oLH and oFSH. 相似文献
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Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study—A Randomized Clinical Trial
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A. Boswood J. Häggström S.G. Gordon G. Wess R.L. Stepien M.A. Oyama B.W. Keene J. Bonagura K.A. MacDonald M. Patteson S. Smith P.R. Fox K. Sanderson R. Woolley V. Szatmári P. Menaut W.M. Church M. L. O'Sullivan J.‐P. Jaudon J.‐G. Kresken J. Rush K.A. Barrett S.L. Rosenthal A.B. Saunders I. Ljungvall M. Deinert E. Bomassi A.H. Estrada M.J. Fernandez Del Palacio N.S. Moise J.A. Abbott Y. Fujii A. Spier M.W. Luethy R.A. Santilli M. Uechi A. Tidholm P. Watson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2016,30(6):1765-1779
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Luke A. J. Haydock Anthony C. G. Abrams-Ogg J. Scott Weese Michael R. Goldstein Amy B. Clifford Adrian Sebastian Elizabeth H. Rea Frances B. Jamieson Carla Duncan Olga Andrievskaia Mirjana Savic Durda Slavic Robert A. Foster Christopher J. Greenwood Tamara L. MacDonald Jacqueline E. Scott Andrea Sanchez 《Journal of veterinary diagnostic investigation》2022,34(2):292
A 4-y-old, female mixed-breed dog was presented to the Ontario Veterinary College for further evaluation of multiple pulmonary and hepatic masses, intrathoracic lymphadenitis, and recent development of a pyogranulomatous pleural effusion. Along with other comprehensive tests, a thoracic lymph node biopsy was performed, and Mycobacterium tuberculosis complex infection was confirmed by real-time PCR. The dog’s condition declined post-operatively, and euthanasia was elected. Postmortem examination confirmed severe granulomatous pneumonia, hepatitis, intrathoracic and intraabdominal lymphadenitis, omentitis, and nephritis. Line-probe assays performed on samples collected postmortem confirmed the species as M. tuberculosis. 24-loci MIRU-VNTR genotyping, spoligotyping, and whole-genome sequencing revealed relations to known human isolates, but no epidemiologic link to these cases was investigated. Given the concern for potential human exposure during this animal’s disease course, a public health investigation was initiated; 45 individuals were tested for M. tuberculosis exposure, and no subsequent human infections related to this animal were identified. Our case highlights the need for more readily available, minimally invasive testing for the diagnosis of canine mycobacteriosis, and highlights the ability of canid species to act as potential contributors to the epidemiology of M. tuberculosis infections. 相似文献
6.
J. Gordon Bell Douglas R. Tocher Fiona M. MacDonald John R. Sargent 《Fish physiology and biochemistry》1994,13(2):105-118
Three practical-type diets utilizing fishmeal and casein as the protein sources and containing fish oil (FO), safflower oil
(SO) or linseed oil (LO) were fed to duplicate groups of juvenile turbot (Scophthalmus maximus) of initial weight 1.2 g for a period of 12 weeks. No differences in final weight, mortality or development of pathological
lesions were evident either between duplicate tanks or between dietary treatments over this period. Fish fed diets containing
SO and LO contained significantly greater amounts of liver triacylglycerol compared to fish fed FO. The major C18 polyunsaturated fatty acids (PUFA) in SO and LO diets, 18:2(n-6) and 18:3(n-3) respectively, were readily incorporated into
both total lipid and individual phospholipids of turbot tissues. There was no accumulation of the Δ6-desaturation products
of these fatty acids, namely 18:3(n-6) and 18:4(n-3), in any of the tissues examined. The products of elongation of 18:2(n-6)
and and 18:3(n-3), 20:2(n-6) and 20:3(n-3) respectively, accumulated in both total lipid and phospholipids with the highest
levels of 20:2(n-6) in liver PC and 20:3(n-3) in liver PE. Eicosapentaenoic acid [EPA, 20:5(n-3)] levels exceeded those of
arachidonic acid [AA, 20:4(n-6)] in phosphatidylinositol (PI) from liver and gill of fish fed LO. EPA levels in liver PI from
fish fed LO were 3-fold and 2-fold greater than SO-fed and FO-fed fish, respectively. Fish fed diets containing SO and LO
had significantly reduced levels of AA in liver and muscle total lipid and lower AA in individual phospholipid classes of
liver and gill compared to FO-fed fish. The concentration of thromboxane B2 was significantly reduced in plasma and isolated gill cells stimulated with calcium ionophore A23187 of fish fed SO and LO
compared to those fed FO. Prostaglandin E produced by isolated gill cells stimulated with A23187 was significantly reduced
in fish fed both SO and LO compared to fish fed FO. 相似文献
7.
OBJECTIVE: To report clinical experience with arthrodesis of the proximal interphalangeal joint in horses using two parallel 5.5-mm cortical bone screws placed in lag fashion. STUDY DESIGN: Retrospective, clinical study. ANIMALS: Thirty-four horses, aged 1 to 19 years. METHODS: Medical records for all horses admitted (1991-1997) for pastern arthrodesis using two 5.5-mm ASIF cortical bone screws, in parallel orientation, and placed in lag fashion by use of a combined aiming device to facilitate accuracy were reviewed. Signalment, lameness diagnosis, duration of lameness, limb(s) involved, and outcome were recorded. Criteria for successful outcome were determined as return to previous level of function or future intended athletic use. RESULTS: Thirty-nine proximal interphalangeal joint arthrodeses were performed on 34 horses. One horse was euthanatized in the recovery room and was excluded from data analysis. Successful outcome occurred in 85% of frontlimbs and 89% of hindlimbs. Failure occurred in 5 joints; 1 horse had lameness directly associated with surgery, whereas 4 horses had unrelated lameness. CONCLUSION AND CLINICAL RELEVANCE: Age, breed, and initial disease did not affect outcome. Arthrodesis of the proximal interphalangeal joint by use of two 5.5-mm ASIF cortical bone screws, in parallel orientation, placed in lag fashion by use of a combined aiming device, resulted in sound use of the limb in >85% of the joints with shortened postoperative coaptation. 相似文献
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