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101.
1994年6月中旬从韩国出口7~13g/尾牙鲆苗8万尾,利用室内循环水锅炉升温进行工厂化养殖9个月,平均体重500g以上,达到商品规格,养殖过程中,试验了放养密度,投饵,水质管理及腹水病,纤毛虫病的防治技术。 相似文献
102.
R.H Dunlop S.A McEwen A.H Meek R.C Clarke W.D Black R.M Friendship 《Preventive veterinary medicine》1998,34(4):1610-305
Logistic regression was used to model associations between antimicrobial treatment and resistance among fecal Escherichia coli of finisher pigs at the farm level. Four sets of potential risk factors representing different levels of refinement of antimicrobial use on farms were modelled on resistance to antimicrobials. Final models for each antimicrobial were constructed from treatment and management variables significant on initial screening, and corrections for overdispersion were made. In general, in-feed antimicrobial treatment of pigs was more consistently associated with an increased risk of resistance than individual-animal treatment. Antimicrobial treatment in starter rations was significant in final models of resistance to ampicillin, carbadox, nitrofurantoin, sulfisoxizole, and tetracycline. Treatment in grower–finisher rations was significantly associated with resistance to ampicillin, spectinomycin, sulfisoxizole, and tetracycline. There was little evidence that in-feed antimicrobials increased the risk of resistance to gentamicin, which is a drug used only for individual-pig treatment in this study population. These results suggest that antimicrobial medication of rations of post-weaning pigs selects for and maintains antimicrobial resistance among E. coli of finisher pigs. Although resistance was common on farms that did not medicate rations of post-weaning pigs, the results indicate that antimicrobial use does increase the risk of resistance to the antimicrobials studied. 相似文献
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Retrospective evaluation of cats with elapid snake envenomation associated neurotoxicity requiring mechanical ventilation: 12 cases (2005–2014) 下载免费PDF全文
105.
Christopher R. Lamb MA VetMB Lawrence J. Kleine DVM MS Majorie C. McMillan DVM 《Veterinary radiology & ultrasound》1991,32(5):211-220
A wide variety of normal and pathologic factors may induce intraabdominal calcification. In general, the most reliable indication of the cause of a calcification is its location; therefore, if the affected organ can be identified the radiographic diagnosis is often straightforward or, at least, limited to relatively few possibilities. With this principle in mind, a series of patients with abdominal calcification are described for the purpose of illustrating the appearance of calcification of various abdominal organs. In addition, etiology for the calcification in each patient is discussed. Certain extraabdominal calcifications which may be seen on abdominal radiographs are also mentioned. 相似文献
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生物技术在畜牧业上的应用研究 总被引:1,自引:0,他引:1
从生物技术与畜禽品种、动物遗传育种,动物饲料资源开发,动物疫病的预防与诊断几个方面,论述了其在畜牧业中的应用,以期用生物技术来推动我国畜牧业的更快发展。 相似文献
110.
摘要:针对大棚辣椒多年连续种植,导致大棚辣椒病虫害发生逐年加重、辣椒大幅减产、品质下降等问题,基于大棚辣椒主要病虫害发生特点及规律,通过试验和示范、推广,形成了1套以生态调控技术、生物防治技术、害虫诱杀技术和科学用药技术等为主要内容的全程绿色防控模式,并在生产中不断推广应用,病虫害防治效果达95%以上,化学农药使用量减少50%以上,农药残留合格率100%,提高了辣椒产量和品质,保证了农产品质量安全,生态效益显著;绿色防控区产投比(6.781)明显高于常规防控区(4.681),667 m2净收益较常规防控区高出4 111.0元,经济效益较好。 相似文献