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21.
众所周知,目前市场上有多种形式的金属复合物可供在动物营养中使用;当特定的微量元素与有机分子络合或结合的时候,这些复合物统称为“有机微量元素”。  相似文献   
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过去的二十多年里,有机矿物质已作为微量矿物质的部分替代品使用,用以提高家禽某些方面的生产性能,如种鸡受精率、蛋壳强度及胴体和肉品质量.但是,当前研究发现:用更低水平但更易吸收的OTMs替代无机微量元素,可以最大限度减少矿物质排泄量并使与矿物质相关的生长性能性状最优化,这便给了我们更大的想象空间.  相似文献   
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An 11-year-old, female, spayed cocker spaniel was presented with dysphonia caused by a solitary laryngeal mass. Excisional biopsy was performed, and a diagnosis of plasmacytoma was made on the basis of histological examination. Further investigations showed no signs of systemic involvement. Coarse fractionated radiation therapy failed to control the tumour. Therapy was successfully instituted with a conventional combination chemotherapy protocol over a period of 14 months. The dog remains disease free 30 months after diagnosis. Most solitary, extramedullary plasmacytomas in dogs arise in the gastrointestinal tract, with fewer reports in other sites. The larynx is an uncommon sight of involvement in any species, and to the authors' knowledge, this is the first report of this tumour type in the canine larynx. In contrast to the therapeutic benefits reported in humans, the combination of surgery and radiation therapy was unsuccessful in this case, although sustained remission was gained following chemotherapy.  相似文献   
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Otitis externa, inflammation of the externa ear canal, is relatively easy to diagnose based on the history and physical examination findings. The diagnosis of otitis media, inflammation of the middle ear cavity, is more challenging, with the work-up being both costly and, at times, invasive. The pathogenesis of otitis externa has been classified into predisposing, primary, and perpetuating factors. It is critical to the management of ear disease that the clinician recognize and investigate which factors are contributing to each individual patient's ear disease. Failure to identify and address the primary and/or predisposing factors is the most common cause of chronic recurrent otitis externa. Chronic inflammation of the ear canal leads to the development of the perpetuating factors, which may be the major reason for treatment failure, regardless of the primary cause of the ear disease. In this article, the predisposing, primary, and perpetuating factors involved in ear disease will be presented, along with a review of the techniques used in the diagnosis of otitis externa and otitis media.  相似文献   
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Reference intervals for serum protein electrophoresis (SPE) were created from a group of 75 clinically healthy dogs and compared with SPE results obtained from clinical cases presented to the University of Bristol over an eight-and-a-half-year period. A total of 147 dogs, in which SPE had been performed, had complete case records available and thus met the inclusion criteria. Signalment and final diagnoses taken from the case records and SPE results were divided into normal and abnormal based on the newly established reference intervals. Cases were grouped according to the SPE protein fraction abnormalities and diagnosis using the DAMNITV classification system. Of the 147 cases, 140 (95.2 per cent) had abnormal SPE results. The most common protein fraction abnormality was decreased albumin (59.3 per cent) followed by a polyclonal increase in γ globulins (38.6 per cent). Decreased β-1 globulins and increased β-2 globulins were documented in 36.4 and 30.0 per cent of cases, respectively. The most common DAMNITV classification associated with abnormal SPE results was infectious/inflammatory disease, which was diagnosed in 79 of 140 cases (56.4 per cent). Monoclonal gammopathies were noted in eight dogs (5.7 per cent), and underlying lymphoproliferative disease was present in all cases where a diagnosis was achieved, including multiple myeloma (four dogs), splenic plasmacytoma (one dog), hepatic plasmacytoma (one dog) and lymphoma (one dog).  相似文献   
26.
Oral mucocutaneous lymphoma is rare in dogs. Surgery and chemotherapy do not usually provide effective long-term control. The objective of this study was to retrospectively evaluate survival of dogs with localized oral lymphoma treated with radiation therapy. The medical database of three institutions was searched for dogs with diagnosis of oral lymphoma treated with radiotherapy. Dogs with evidence of systemic disease were excluded. Survival was calculated with the Kaplan-Meier method and prognostic variables analysed with log-rank test. Fourteen dogs were included in the study. Mean survival was 1129 days [95% confidence interval (CI) 711-1546] with median survival of 770 days. The overall response of radiotherapy was 67% (five complete and three partial responses). A survival advantage was seen in dogs with no evidence of lymph node metastasis (P = 0.002) and that achieved a complete response to radiation therapy (P = 0.013). Radiation therapy was a well-tolerated and effective treatment for localized oral lymphoma.  相似文献   
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本试验的氮源是纯化大豆蛋白(IsolatedSoybeanProtein,ISP)和尿素(NPN),按80:20、50:50和20:80分3组;碳水化合物源分别是从干草中提取的中性洗涤纤维(NDF)、玉米淀粉和蔗糖,按10:85:5、10:80:10、10:75:15、30:65:5、30:60:10、30:55:15、50:45:5、50:40:10和50:35:15分9组的3×9因子实验设计。应用体外尼龙袋发酵技术,研究了奶牛日粮不同来源氮和碳水化合物及其比例对干物质(DM)体外降解率的影响。结果表明,过量补充尿素及随着日粮中淀粉和蔗糖比例的增加,日粮干物质的体外降解率均下降。根据试验结果,建议在泌乳期奶牛的全混合日粮中尿素的补充量应低于干物质的2.8%,非结构性碳水化合物的含量不应超过干物质的45%。  相似文献   
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