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141.
H. T. Koch R. A. I. Norval J. G. R. Ocama F. C. Munatswa 《Preventive veterinary medicine》1992,12(3-4):197-203
In two trials, Theileria parva bovis (which causes ‘January disease’ of cattle in Zimbabwe) produced a carrier state, over the 7–12 months after infection. Very severe clinical reactions were caused by infections from small numbers (29–43) of adult Rhipicephalus appendiculatus ticks, which had engorged on immunized cattle in the field. The transmission from healthy recovered cattle housed indoors was less efficient, even with high numbers of ticks (300). Two out of seven attempts were successful and disease reactions were rather severe. A non-pathogenic Theileria assumed to be Theileria taurotragi was transmitted in three out of seven attempts. 相似文献
142.
桑蚕摘除部分感觉器对人工饲料摄食性的影响 总被引:4,自引:0,他引:4
桑蚕摘除了触角,下颚须或下颚瘤状体后,对人工饲料的摄食性均显著提高,摄食性个体差异减小,对桑叶或人工饲料正趋性强的个体,其摄食性较高,人工饲料中不仅存在蚕的味觉有明显抑制作用的物质,也存在对嗅觉有忌避作用的成分,嗅觉在决定对人工饲料摄食性方面具有重要作用。 相似文献
143.
通过计算ELD50,将已知效价的鸡传染性法氏囊病(B87株)生产种毒分几个滴度进行稀释,分别接种SPF鸡胚,结果各组鸡胚随病毒接种量的提高,高峰期死亡时间逐渐靠前,高峰期死亡率也逐渐增加,抗原效价也逐渐提高,抗原产量也有明显变化,病毒滴度以102.0ELD50/0.1mL接种鸡胚更合适。 相似文献
144.
Epidemiological studies on bovine ocular carcinoma were reviewed. Reports on the frequency and the distribution of the disease indicate that it is still a very prevalent and economically important disease. It is recognized throughout North America, but is more frequent in lower latitudes under range conditions. Etiological factors including ultraviolet light, circumocular apigmentation and viruses, as well as the pathogenesis, are considered in light of current knowledge on carcinogenesis of this tumor. It is likely that the induction of bovine ocular carcinoma is multifactorial and the precise roles played by each of the various factors are not yet understood. 相似文献
145.
146.
A puppy was evaluated for rapid growth and large stature. Extensive diagnostic evaluation suggested a growth hormone independent disorder. As the sole detected abnormality was elevated leptin concentration, an obesity syndrome causing leptin resistance was speculated to explain the puppy's condition but was not confirmed. Except for large body size, the puppy remained clinically normal. 相似文献
147.
Two dogs were presented within 24 hours to the Department of Small Animal Medicine and Surgery at the University of Veterinary Medicine Hannover for investigation of the sudden onset of neurological abnormalities following a walk in the same park. One dog was observed ingesting a piece of meat. Analysis of urine by gas chromatography-mass spectrometry from each of the dogs identified the presence of barbiturates. Both dogs recovered with supportive treatment. This is the first report to describe the use of toxicological urinalysis with gas chromatography-mass spectrometry for the diagnosis of barbiturate intoxication in dogs. 相似文献
148.
149.
重庆蚕丝业在 2 0世纪 80年代末期至 90年代中期居全国第四位 ,不仅是重庆出口创汇的重要支柱 ,也是财政和蚕农收入的重要来源。我国“入世”后 ,蚕丝业是重要的受益行业 ,面临巨大的市场需求与发展空间。根据中央西部大开发战略 ,结合我国丝绸产业结构调整、东桑西移的历史机遇和重庆得天独厚的茧丝绸资源 ,就新世纪重庆蚕丝业发展存在的问题和应采取的措施谈几点意见。1 重庆蚕丝业的发展现状及问题1 .1 现状在重庆 40个区县 (市 )行政区划中 ,有养蚕的区县 (市 ) 35个 ,蚕种场 2 7个 ,蚕种冷库6座 ,年制种能力 1 30余万张、年冷藏能力2… 相似文献
150.
A computer program for calculation of doses and prices of injectable medications based on body weight or body surface area 总被引:1,自引:0,他引:1 下载免费PDF全文
A computer program (CalcAnesth) was developed with Visual Basic for the purpose of calculating the doses and prices of injectable medications on the basis of body weight or body surface area. The drug names, concentrations, and prices are loaded from a drug database. This database is a simple text file, that the user can easily create or modify. The animal names and body weights can be loaded from a similar database. After typing the dose and the units into the user interface, the results will be automatically displayed. The program is able to open and save anesthetic protocols, and export or print the results. This CalcAnesth program can be useful in clinical veterinary anesthesiology and research. The rationale for dosing on the basis of body surface area is also discussed in this article. 相似文献