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31.
This paper reports physical, psychological, and chemical hazards relevant to western Canadian veterinarians as obtained by a self-administered mailed questionnaire. Nine-three percent (750/806) of veterinarians reported some form of injury during the previous 5 years; 17% of respondents (131/791) indicated injuries that resulted in 1 or more days off work. Median stress levels were similar across work environments; overall, 7% (57/813) indicated either no stress or severe stress, while 53% (428/813) indicated moderate stress. Twenty percent (3/15) of food animal practitioners and 37% (114/308) of companion animal practitioners who took X-rays reported accidental exposure. Accidental exposure to gas anesthetic was reported by 69% (394/570) of those in private practice. Exposure to chemicals occurred in all work environments. Veterinarians in western Canada are at risk of minor to severe injury due to both animal and non-animal related causes.  相似文献   
32.
Passive surveillance of ticks on horses in Saskatchewan revealed that the horses were parasitized by 3 species, Dermacentor albipictus, D. andersoni, and D. variabilis. The nymphs and adults of D. albipictus occurred on horses earlier in the year than did adults of the 2 other species.  相似文献   
33.
From 2007 to 2019, the Western College of Veterinary Medicine Disease Investigation Unit conducted lead investigations in 12 beef cow-calf herds and tested 1104 presumed exposed but clinically unaffected cattle, 49 of which were unsafe for slaughter (blood lead ≥ 0.1 ppm). In all investigations, the lead source should be evaluated, and all potentially exposed animals intended for food should be tested. Clinically affected animals should be tested individually. Individual testing of clinically unaffected animals may be expensive for large groups. However, pooling a conservative number of blood samples (n = 2 to 5) from clinically unaffected cattle may efficiently identify groups that are safe for slaughter. If a pooled test produces a blood lead concentration over the minimum threshold (0.1 ppm/n), these samples should be individually re-tested. Herd size, lead toxicity prevalence, pool size, and number of pools that require individual re-testing all affect the potential cost savings of pooled testing.  相似文献   
34.
This study investigated the relationship between treatment protocol, survival to discharge, and relapse in 46 dogs diagnosed with primary immune-mediated thrombocytopenia (ITP) at the Western College of Veterinary Medicine between 2000 and 2013. Treatment was at the discretion of the attending clinician and consisted of either a corticosteroid alone or a corticosteroid plus a secondary therapy. There was no association between survival to discharge and treatment protocol (P = 0.23). Of the surviving in-patients, 39% experienced a relapse. Our study failed to show a significant difference in survival and relapse based on treatment protocol.  相似文献   
35.
Grigg RW  Epp D 《Science (New York, N.Y.)》1989,243(4891):638-641
Coral islands drown when sea level rise exceeds the maximum potential of coral reefs to grow upward (about 10 millimeters per year). During the Holocene transgression (18,000 years ago to present) sea levels rose at rates of up to 10 to 20 millimeters per year, and most coral island reefs situated deeper than a critical depth of30 to 40 meters below present day sea level drowned. Coral islands that did not drown during the Holocene transgression apparently all developed on antecedent foundations shallower than critical depth. During low stands in sea level during the Pleistocene, these islands were elevated and subject to subaerial erosion. Today, in the Hawaiian Archipelago, the depth of drowned banks is inversely related to summit area; smaller banks are progressively deeper, evidently because of erosional truncation during low sea level stands. Bank summit area may therefore be an important factor determining the failure or success of coral islands.  相似文献   
36.
The aim of this work was to optimize a supercritical fluid extraction (SFE)/enzymatic reaction process for the determination of the fatty acid composition of castor seeds. A lipase from Candida antarctica (Novozyme 435) was used to catalyze the methanolysis reaction in supercritical carbon dioxide (SC-CO(2)). A Box-Behnken statistical design was used to evaluate effects of various values of pressure (200-400 bar), temperature (40-80 degrees C), methanol concentration (1-5 vol %), and water concentration (0.02-0.18 vol %) on the yield of methylated castor oil. Response surfaces were plotted, and these together with results from some additional experiments produced optimal extraction/reaction conditions for SC-CO(2) at 300 bar and 80 degrees C, with 7 vol % methanol and 0.02 vol % water. These conditions were used for the determination of the castor oil content expressed as fatty acid methyl esters (FAMEs) in castor seeds. The results obtained were similar to those obtained using conventional methodology based on solvent extraction followed by chemical transmethylation. It was concluded that the methodology developed could be used for the determination of castor oil content as well as composition of individual FAMEs in castor seeds.  相似文献   
37.
The primary objectives of this study were to determine the seroprevalence of West Nile virus (WNV) infection of horses in Saskatchewan in 2003 and to identify risk factors for the infection. Blood samples were collected in August and October from 212 horses in 20 herds in 5 geographic zones. After accounting for within-herd clustering, the proportion of horses that had been infected with WNV, as determined by IgG and IgM antibody response, was 55.7% (95% confidence interval, 44.9% to 65.8%). The proportion of antibody-positive horses differed among herds (0% to 100%) and across ecoregions (20% to 76%). Horses in southern ecoregions were more likely to have either IgM antibodies or IgG concentrations suggesting infection than were horses in northern ecoregions. The use of mosquito-control measures was associated with decreased risk. After accounting for ecoregion, there was no difference between recipients of an inactivated WNV vaccine and nonrecipients in the occurrence of antibodies reflecting natural infection.  相似文献   
38.
Spores, pollen, and charcoal taken from two wells drilled near the tip of Cape Cod have been identified as Eocene. These are the first Eocene rocks to be identified in Massachusetts. Interpretation of seismic records taken in the Gulf of Maine and Cape Cod Bay will be influenced by this discovery.  相似文献   
39.
Ultrasonography was used to capture a coronal–sagittal image of the veins of the pampiniform plexus (PP) and the testicular artery of 327 maternal‐line boars at approximately 6 months of age at the University of Nebraska—Lincoln. Varicocoele was diagnosed by two methods. Method 1 diagnosed varicocoele when the average vessel area on one side of the scrotum was 1.5 times larger than the average vessel area on the other side of the scrotum. Method 2 diagnosed varicocoele when the average vessel area on one side of the scrotum of a boar was 1.5 times larger than the average vessel on the same side of the scrotum of the boar's cohorts (same population and year). Varicocoele was diagnosed in 23.17% and 15.1% of boars measured using method 1 and method 2, respectively. Ultrasonography showed to be an effective means to measure PP vessel size in boars and may even allow for earlier detection of varicocoele than by using palpation. Animal models were employed to estimate the heritability for: average area of right PP vessels (0.52), average area of the left PP vessels (0.46), varicocoele presence using method 1 (0.26) and varicocoele presence using method 2 (0.25). These heritability estimates suggest that vessel size and varicocoele could be selected against in breeding programmes to potentially improve boar semen quality.  相似文献   
40.
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