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101.
In the Boundary Waters Canoe Area Wilderness, the movement of fecal bacteria, N, and P from pit latrines was studied, as well as the effectiveness of peat latrine liners in reducing this movement. When latrines are constructed where only a thin layer of permeable soil overlies bedrock or other impermeable material, fecal bacteria can be carried considerable distances by subsurface flow. Lining latrine pits with acid peat appears to reduce bacteria transport. Most soils strongly adsorb P and prevent its movement. In this study no movement of P from latrine pits was seen except at one site with very sandy soil. In such soil a peat liner appears to be of some value, if a peat with a high P adsorption capacity is used. A peat liner should be viewed as an additional protection against P and bacteria movement rather than as a substitute for proper soil conditions. Latrines should not be built in thin, rocky soils. Nitrogen appears to move readily from toilet pits, regardless of soil type or presence of peat liners. But, because of dilution, N is not likely to have a discernible impact on water quality. 相似文献
102.
ABSTRACT: Q fever is a worldwide zoonosis caused by the bacterium Coxiella burnetii. The control of this infection in cattle is crucial: infected ruminants can indeed encounter reproductive disorders and represent the most important source of human infection. In the field, vaccination is currently advised in infected herds but the comparative effectiveness of different vaccination protocols has never been explored: the duration of the vaccination programme and the category of animals to be vaccinated have to be determined. Our objective was to compare, by simulation, the effectiveness over 10 years of three different vaccination strategies in a recently infected dairy cattle herd.A stochastic individual-based epidemic model coupled with a model of herd demography was developed to simulate three temporal outputs (shedder prevalence, environmental bacterial load and number of abortions) and to calculate the extinction rate of the infection. For all strategies, the temporal outputs were predicted to strongly decrease with time at least in the first years of vaccination. However, vaccinating only three years was predicted inadequate to stabilize these dynamic outputs at a low level. Vaccination of both cows and heifers was predicted as being slightly more effective than vaccinating heifers only. Although the simulated extinction rate of the infection was high for both scenarios, the outputs decreased slower when only heifers were vaccinated.Our findings shed new light on vaccination effectiveness related to Q fever. Moreover, the model can be further modified for simulating and assessing various Q fever control strategies such as environmental and hygienic measures. 相似文献
103.
Miller M Terrell S Lyashchenko K Greenwald R Harris B Thomsen BV Fontenot D Stetter M Neiffer D Fleming G 《Journal of zoo and wildlife medicine》2011,42(3):468-472
Two adult female bontebok (Damaliscus pygarus dorcas) were euthanized because of signs of pneumonia and weakness (case 1), and a nonresponsive lameness with draining fistula (case 2). Necropsy findings were similar in both cases and consisted of disseminated granulomatous lesions in the liver, kidneys, spleen, lungs, pleural surfaces, and multiple lymph nodes. Mycobacterium kansasii was isolated from both cases after multiple attempts on a variety of samples by two laboratories. The remaining four animals in the herd were tested for antibody responses using the Chembio ElephantTB STAT-PAK, DPP VetTB kits, and multi-antigen print immunoassay (MAPIA), for immune reaction using the intradermal tuberculin test, and by tracheal wash cultures, and thoracic radiographs. Banked serum samples collected in 2005 and obtained from the original institution, revealed 1/9 (11.11%) seropositive animals using the three immunoassays. Retesting the current herd in 2008 showed 2/6 (33.33%) seropositive animals by the three tests, with MAPIA demonstrating antibody reactivity to MPB83 and MPB70 proteins. Inconsistent intradermal tuberculin test results, cross-reactivity in serologic assays designed for tuberculosis detection, difficulty in obtaining definitive identification by culture, and inability to identify a source of infection created challenges in distinguishing the atypical mycobacteriosis due to M. kansasii from the initially suspected tuberculous infection in this herd. Owing to regulatory considerations, differences in host-to-host transmission, and source of infection between Mycobacterium tuberculosis complex and nontuberculous mycobacteria, correct diagnosis is crucial for management of these diseases in wildlife species. 相似文献
104.
Zamprogno H Hash J Hulse DA Lascelles BD 《Veterinary journal (London, England : 1997)》2011,190(2):220-224
The objective of this study was to develop a surgical technique for sensory denervation of the canine elbow joint and to assess the effects of denervation on limb function in normal dogs. Twenty cadavers (40 elbows) were used to characterize innervation and design the surgical protocol which was tested in 13 cadavers (26 normal elbows). The effect of denervation on limb function was assessed in vivo in four dogs with the elbow randomly selected for the procedure. Primary outcome measures were static bodyweight distribution and distal limb mechanical sensory thresholds; secondary outcome measures were subjectively scored lameness, neurological function and pain on manipulation. Histology was performed on all resected tissues to determine whether nerves had been resected. Denervation was achieved by separate medial and lateral surgical approaches. In testing the developed surgical protocol, 111/130 resected samples contained nerve tissue in the healthy cadaveric elbows and 18/20 in the in vivo study. Limb function and sensation were not altered by elbow joint denervation. The protocol developed for denervation of the canine elbow appears feasible and does not result in any sensory or motor deficits of the forelimb. 相似文献
105.
七株旋毛虫几项生物学特性的比较研究 总被引:6,自引:1,他引:5
对采自我国哈尔滨、长春、天津、西安、河南邓县、新野及云南保山的7株旋毛虫的成虫形态及幼虫在肌组织中寄生、成囊等作了比较研究。原始虫株除长春株采自犬外,其余6林原始宿主均为猪。虫株用大白鼠及小白鼠继代。结果表明,7个虫株在光镜形态学上无差异,但长春犬株3日龄及7日龄成虫的大小明显小于其它6个虫株,对小白鼠的感染性较低,幼虫卷曲、成囊均较晚,而且幼虫有钙化、死亡现象。 相似文献
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John B. Kaneene Martin Saffell Don J. Fedewa Kenneth Gallagher H.Michael Chaddock 《Preventive veterinary medicine》1997,29(4):263-275
The Michigan equine monitoring system (MEMS) was designed and implemented in the State of Michigan, starting in 1991. The program was designed systematically to track the State's equine population, its health, and its economic implications to the equine industry. The MEMS was designed as a two-phase program. Phase I (the population and economic survey; the subject of this paper) was designed to provide new and statistically valid information describing the size, composition, location and economic characteristics of the Michigan equine industry. A standardized questionnaire was used to collect data via mail, telephone and personal interviews.
Of the 3000 randomly selected list-frame samples, 2800 (93%) participated. However, 650 of these had no equids. There were 129932 equids reported compared with 160000 in 1984. The American Quarter Horse, Standardbred and Arabian breeds were the most numerous. Detailed results, including the size of equine operations/herds, uses, geographical distribution and the financial structure of the industry, are presented. A detailed account of the strategies used in designing and implementing the system is provided. 相似文献
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