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191.
The objective of this study was to generate demographic data on veterinarians working in western Canada. A sample of 551 veterinarians was randomly selected from a population of 2474 veterinarians employed in western Canada, 425 (77.1%) of whom responded to the survey. The respondents were evenly split between males (53.1%) and females (46.9%). More than half (58.0%) of the private practitioners practised exclusively on companion animals (small animals and horses), while 2.9% devoted 100% of their time to food animals. There were 351 respondents who had had ≥ 2 employers since graduation; 80% of those who had begun their careers in companion animal (CA) practice had remained in this type of practice, while 54.3% of those who had begun their careers in mixed animal practice had switched to CA practice. Analyses of wage and workload data from 85 full-time veterinary employees showed that CA practitioners worked the fewest hours/week (47.0), had the least number of evenings on-call/month (3.7), and earned the highest hourly wage ($35.79) as compared with non-CA practitioners.  相似文献   
192.
Surgical resection of a dysgerminoma in a mare   总被引:1,自引:1,他引:0  
A mare was referred for further evaluation of a mass found in the left caudal abdomen during a routine postpartum reproductive palpation. The mare was clinically normal with no history of health problems. Ultrasonographic examination of the mass confirmed its presence, but the origin of the mass could not be accurately determined. Routine haematology and serum biochemistry results were within normal limits. The mare was initially treated conservatively with antibiotics, but the mass continued to increase in size, so it was surgically excised. The mass involved the left ovary. The mare showed transient abdominal pain after surgery, but developed no other complications and was in foal 7 months later. On histology, the mass was diagnosed as a dysgerminoma, a rare ovarian tumour of germ cell origin.  相似文献   
193.
A series of abortions occurred in mares in New South Wales during 2004 that involved similar and unusual findings on post mortem examination of aborted fetuses and fetal membranes. The term Equine Amnionitis and Fetal Loss (EAFL) was developed to describe the condition. This form of abortion had not been previously recognised in Australia. The pathology alone is not specific for EAFL and diagnosis requires demonstration of a combination of certain pathological and bacteriological features. The purpose of this paper is to describe patterns considered consistent with EAFL cases as a working case definition for use by veterinarians and veterinary pathologists in identifying future cases of EAFL. More detailed papers are in preparation to fully describe the epidemiological, histopathological, and microbiological aspects of EAFL.  相似文献   
194.
The accuracy of the Rice pelvimeter for measuring pelvic area of double muscled Belgian Blue (BB) cattle was investigated by comparing measurements in the live animal with these obtained from the same animal after slaughter. Pelvic measurements from 466 BB-cows aged 2–10 years old and of an excellent carcass qualification (S and E in the SEUROP classification) were measured with the pelvimeter approximately 12 h prior to, and by graded ruler within 2 h after, slaughter. The mean difference of measurements between living and dead cattle were − 0.2 cm for pelvic width (95% limits of agreement − 2.5–2.1 cm), and 1.2 cm for pelvic height (95% limits of agreement − 1.8–4.1 cm). The correlation coefficient between all pelvic measurements was between 0.46 and 0.59 (p < 0.001). The age of the animals influenced only pelvic height whilst carcass weight influenced all the components of the pelvic area. There was a significant correlation between the pelvimetric measurements of the birth canal in living cattle obtained using a Rice pelvimeter compared to actual measurements obtained from the carcass. The Rice pelvimeter is a suitable tool for assessing accurate pelvic skeletal conformation and to select animals in this breed with a larger birth canal and hence less dystocia problems.  相似文献   
195.
196.
No gold standard assay exhibiting error‐free classification of results has been identified for detection of Renibacterium salmoninarum, the causative agent of salmonid bacterial kidney disease. Validation of diagnostic assays for R. salmoninarum has been hindered by its unique characteristics and biology, and difficulties in locating suitable populations of reference test animals. Infection status of fish in test populations is often unknown, and it is commonly assumed that the assay yielding the most positive results has the highest diagnostic accuracy, without consideration of misclassification of results. In this research, quantification of R. salmoninarum in samples by bacteriological culture provided a standardized measure of viable bacteria to evaluate analytical performance characteristics (sensitivity, specificity and repeatability) of non‐culture assays in three matrices (phosphate‐buffered saline, ovarian fluid and kidney tissue). Non‐culture assays included polyclonal enzyme‐linked immunosorbent assay (ELISA), direct smear fluorescent antibody technique (FAT), membrane‐filtration FAT, nested polymerase chain reaction (nested PCR) and three real‐time quantitative PCR assays. Injection challenge of specific pathogen‐free Chinook salmon, Oncorhynchus tshawytscha (Walbaum), with R. salmoninarum was used to estimate diagnostic sensitivity and specificity. Results did not identify a single assay demonstrating the highest analytical and diagnostic performance characteristics, but revealed strengths and weaknesses of each test.  相似文献   
197.
BACKGROUND: Captan is an important fungicide for controlling diseases in horticultural crops. Predicting its dissipation is important for estimating dietary risks and optimising pesticide application. Experiments were conducted to determine the relationship of captan loss on apple leaves with temperature, humidity and rainfall, and to investigate captan loss on fruit in dry conditions. RESULTS: There was large unit-to-unit variability in captan residues in spite of the controlled application. Temperature and humidity had negligible effects on captan loss. Captan loss is predominately due to washoff by rain, although a certain proportion of captan may bind to the plant surface tightly and hence may not be readily removed by rain. About 50% of captan can be washed off by as little as 1 mm of rain after an application, and the loss appeared not to relate to the amount of rain. Under dry conditions, daily loss of captan is estimated to be around 1% on both fruit and leaves, giving a half-life of ca 70 days. CONCLUSIONS: Captan loss on leaf and fruit surfaces is primarily due to rain washoff.  相似文献   
198.
Tallgrass prairie species have evolved with regular exposure to fire. However, burning has been used as a management tool for reducing plant disease in agricultural systems, posing the question of how plant pathogens of tallgrass prairie would be affected by burning. The rust fungus Puccinia dioicae, infecting Erigeron strigosus (Asteraceae), was studied for 8 years in long‐term experiments to evaluate the effects of burning in native tallgrass prairie. This experiment also allowed evaluation of the effects of nutrient additions, although E. strigosus was rare in the plots with added nutrients in most years. Burning reduced rust severity in most years, but effects from additions of nutrients were rarely observed. There was high interannual variation in rust severity within a location, suggesting that weather may be the most important of these three abiotic factors in determining infection. An analysis of weather variables associated with disease severity found that solar radiation in the month prior to sampling was associated with severity in unburned plots; temperature approximately 2 months prior to sampling was also associated with severity in burned plots. High interannual variation also suggests that the effects of this pathogen on its host would be sporadic and difficult to study in short‐term experiments.  相似文献   
199.
200.
Chagas disease is a parasitic infection that can result in a progressive dilated cardiomyopathy. Here, we present the epidemiologic details of a suspected locally acquired transmission case originating from the southern United States. This is the first published report of Chagas disease in a young, healthy United States veteran with repeat triatomine exposures in Arizona. Military personnel and Arizona residents should be aware of their Chagas disease transmission risks.  相似文献   
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