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Stein T Martineau GP Morris R Charette R 《The Canadian veterinary journal. La revue veterinaire canadienne》1987,28(6):355-362
It is proposed that just as the stethoscope and thermometer are fundamental tools for individual medicine, production and health recording systems are fundamental tools for effective population medicine. Treatment and control of clinical diseases as the primary objective is no longer considered appropriate for livestock population. Disease in populations now describes a deviation between what is happening and what is expected to happen. This redefinition of disease implies that it is of multifactorial origin and thus a different problem solving approach must be implemented. Therefore, a swine enterprise must be considered as a system, a set of interdependent components continuously interacting to produce pork. As a system, it is characterized by certain properties: change, environment, counterintuitive behavior, drift to low performance, interdependency, and organization. A redefinition of diseases implies also that they are not only “treated” but managed. Management consists of planning, monitoring, evaluation, and analysis. For this process to be implemented successfully, a goal-directed recording system providing a farm-based infrastructure for problem solving is essential. Clinical problem solving (diagnosis) is thus based on epidemiological and demographic methods. 相似文献
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Evaluation of a Killed Vaccine Against Porcine Pleuropneumonia Due to Haemophilus pleuropneumoniae 总被引:20,自引:2,他引:18
Higgins R Larivière S Mittal KR Martineau GP Rousseau P Cameron J 《The Canadian veterinary journal. La revue veterinaire canadienne》1985,26(2):86-89
A bacterin containing serotypes 1 and 5 of Haemophilus pleuropneumoniae was developed for the prevention and the control of porcine pleuropneumonia. It was injected intramuscularly into three groups of ten piglets, the first group with one dose, the second one with two doses and the third one with three doses at two-week intervals. Another group of ten piglets did not receive the vaccine. All the piglets were then challenged by an aerosol of mixed suspensions of H. pleuropneumoniae serotypes 1 and 5. Two and three injections of vaccine completely prevented mortality, whereas half of the control piglets and of those receiving only one dose of vaccine died. All surviving piglets, both control and vaccinated, had severe signs of respiratory disease for at least 36 hours after exposure to challenge. Moreover, vaccination did not induce the production of antibodies at high titers. Local reactions were not noted after vaccination and at postmortem; ten weeks after the challenge, there were no signs of abscess formation or induration. 相似文献
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英国农业部为家禽饲养者制定了一些新指标,以防止沙门氏菌传染引起家禽流行病。要求饲养产蛋鸡的农民们改善鸡的饲养卫生并进行饲料细菌监测,以保证鸡饲料不受沙门氏菌污染。人们在食过受污染的肉类(尤其是家禽)会引起食物中毒。把研究着重于鸡蛋上是解决这个长期危害大众健康问题的最新方法。目前,一种致病力更强的细菌肠炎沙门氏菌[Salmonella enterit dis]在英国和美国大量增加。由于它能侵入母鸡 相似文献
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Schmitz JA Vogt RJ Rupp GP Brodersen BW Abel JM Wohlers AR Marx DB 《Journal of veterinary medical education》2007,34(3):340-349
Nebraska veterinary practitioners were surveyed to collect data about background characteristics and other factors related to veterinarians' decision to include or not include food animals in their practices and to practice in rural versus urban communities. Background characteristics that were significantly (p < or = 0.05) associated with choosing food-animal practice included growing up on a working farm or ranch; having parents who owned livestock; growing up in a town with a population of less than 10,000; majoring in animal science at university; being male; and having a primary interest, at the time of entering veterinary college, in food animal-exclusive or mixed-animal veterinary practice. The primary factor for choosing the community in which to practice was rural/urban lifestyle for rural veterinarians, while this factor was second for urban veterinarians. For all groups of veterinarians, the primary consideration in selecting their current practice was the species orientation of the practice. The primary reason for not choosing food-animal practice was better working conditions and lifestyle in companion-animal practice, followed by greater interest elsewhere. 相似文献
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Liu WH Yong GP Fang L Wang SK Bai HJ Jiang JH Liu SM 《Journal of agricultural and food chemistry》2008,56(1):185-189
Although phytosterols in tobacco leaves have specific effects on tobacco quality, there is little research on the distribution of free and conjugated phytosterols in various tobacco leaves. In this paper, we explored the content and composition of phytosterols in representative cured tobacco leaves by gas chromatography of TMS-ether derivatives. We found that phytosterol contents in tobacco leaves ranged from 1.0 to 2.5 mg/g of dried leaf tissue, depending on different types of tobacco leaves. The majority of phytosterols (75-85%) were conjugated as ester and glycosides, with only about 15-25% existing in the free form. Furthermore, the genetic variability gives rise to the significant differences among different tobacco types with phytosterol levels: the contents of phytosterols in tobacco leaves decreased in the order of flue-cured tobacco, Oriental tobacco, Burley tobacco, cigar tobacco, and Maryland tobacco. At the same time, the tobacco curing process leads to a difference in phytosterol existing-form distribution in some variation laws. 相似文献
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Role of adenine nucleotide translocator 1 in mtDNA maintenance 总被引:1,自引:0,他引:1
Kaukonen J Juselius JK Tiranti V Kyttälä A Zeviani M Comi GP Keränen S Peltonen L Suomalainen A 《Science (New York, N.Y.)》2000,289(5480):782-785
Autosomal dominant progressive external ophthalmoplegia is a rare human disease that shows a Mendelian inheritance pattern, but is characterized by large-scale mitochondrial DNA (mtDNA) deletions. We have identified two heterozygous missense mutations in the nuclear gene encoding the heart/skeletal muscle isoform of the adenine nucleotide translocator (ANT1) in five families and one sporadic patient. The familial mutation substitutes a proline for a highly conserved alanine at position 114 in the ANT1 protein. The analogous mutation in yeast caused a respiratory defect. These results indicate that ANT has a role in mtDNA maintenance and that a mitochondrial disease can be caused by a dominant mechanism. 相似文献