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41.
周梅  徐成良  郭奎  王重龙 《猪业科学》2020,37(2):120-121
非洲猪瘟是由非洲猪瘟病毒感染家猪或野猪后引发的一种恶性传染病,该疫病在中国的暴发给整个养猪业造成了毁灭性的打击。然而,目前虽有报道称已经有科研单位研制出非洲猪瘟疫苗,但距离其实际应用于生产仍需要相当长的时间。中国是全球最大的猪肉生产和消费国,非洲猪瘟疫情在我国的快速传播使我国生猪产能遭受重创,直接导致猪肉供求失衡、猪肉价格翻番、猪肉市场异动。因此,文章从非洲猪瘟的传播方式、对非洲猪瘟相对有效的防控措施等方面探讨在非洲猪瘟形势下我国养猪业该如何维持产能、如何走好养殖之路。  相似文献   
42.
由副结核分枝杆菌引起牛的副结核病常导致感染牛的慢性增生性肠炎,以及体重、产奶量等生产性能下降,给畜牧业带来了严重的经济损失,目前尚无有效治疗药物。人们常采用不同的检测技术定期对牛群进行监测、淘汰活动带菌期的牛、对牛群进行疫苗接种、采用生物安全防控等措施比较有效地避免了副结核分枝杆菌在牛群中的传播。文章主要从副结核分枝杆菌背景,牛副结核病的危害及防控措施三个方面进行了综述,以期为牛副结核病的防控提供思路。  相似文献   
43.
杨发林 《草业科学》1993,10(1):55-57
对宁夏草原沙化现状、成因及其危害进行了论述,提出了以控制人口数量、提高人口素质为重点的各种治理措施。  相似文献   
44.
饲料中的霉菌毒素及其防制措施   总被引:2,自引:1,他引:2  
霉菌毒素是由真菌或霉菌产生的次级代谢产物,在动物体中,霉菌毒素的毒性是慢性的,很少引起动物死亡。但是霉菌毒素的存在降低了饲料的营养价值,以及动物的生产性能,从而影响生产力,且霉菌毒素在畜产品(肉、奶等)中的残留会给人类健康带来严重威胁。作者主要介绍了饲料中常见的霉菌毒素(黄曲霉毒素、赭曲霉毒素、玉米赤霉烯酮、脱氧雪腐镰刀菌烯醇、T-2毒素、伏马菌素等),以及其毒性和危害,并从预防与去毒两个方面,阐述了霉菌毒素的防制措施,进而减少霉菌毒素造成的危害。  相似文献   
45.
退耕还林还草地鼠类调查及控制对策研究   总被引:3,自引:3,他引:3  
2002-2003年对青海省大通县退耕还林还草地鼠类组成进行调查研究,捕获鼠类6种728只,以根田鼠Microtus oeconomus和高原鼢鼠Myospalax baileyi为绝对优势种.4种方法进行退耕还林还草地害鼠控制的结果表明:人工置夹和药物控制是地上害鼠控制的有效方法,人工地箭与灭鼠雷可有效控制地下高原鼢鼠的数量.但从长远来看,控制退耕还林还草地鼠害应采取生态治理的原则和方法.  相似文献   
46.
Juniper and piñon coniferous woodlands have increased 2- to 10-fold in nine ecoregions spanning the Intermountain Region of the western United States. Control of piñon-juniper woodlands by mechanical treatments and prescribed fire are commonly applied to recover sagebrush steppe rangelands. Recently, the Sage Grouse Initiative has made conifer removal a major part of its program to reestablish sagebrush habitat for sage grouse (Centrocercus urophasianus) and other species. We analyzed data sets from previous and ongoing studies across the Great Basin characterizing cover response of perennial and annual forbs that are consumed by sage grouse to mechanical, prescribed fire, and low-disturbance fuel reduction treatments. There were 11 sites in western juniper (Juniperus occidentalis Hook.) woodlands, 3 sites in singleleaf piñon (Pinus monophylla Torr. & Frém.) and Utah juniper (Juniperus osteosperma [Torr.] Little), 2 sites in Utah juniper, and 2 sites in Utah juniper and Colorado piñon (Pinus edulis Engelm). Western juniper sites were located in mountain big sagebrush (A. tridentata ssp. vaseyana) steppe associations, and the other woodlands were located in Wyoming big sagebrush (A. tridentata ssp. wyomingensis) associations. Site potential appears to be a major determinant for increasing perennial forbs consumed by sage grouse following conifer control. The cover response of perennial forbs, whether increasing (1.5- to 6-fold) or exhibiting no change, was similar regardless of conifer treatment. Annual forbs favored by sage grouse benefitted most from prescribed fire treatments with smaller increases following mechanical and fuel reduction treatments. Though forb abundance may not consistently be enhanced, mechanical and fuel reduction conifer treatments remain good preventative measures, especially in phase 1 and 2 woodlands, which, at minimum, maintain forbs on the landscape. In addition, these two conifer control measures, in the short term, are superior to prescribed fire for maintaining the essential habitat characteristics of sagebrush steppe for sage grouse.  相似文献   
47.
猪繁殖与呼吸综合征防控方法研究进展   总被引:2,自引:0,他引:2  
猪繁殖与呼吸综合征(PRRS)是危害养猪业的一种高度传染性疾病,在临床上以母猪流产、死胎等繁殖障碍以及仔猪呼吸道症状和高死亡率为特征,给养猪业造成了严重的经济损失.目前,PRRS的诊断与综合防治技术已成为国内外兽医学家研究的热点.论文简要概述了近几年来我国对PRRS病原学、临床症状、诊断学及其防控等方面的研究进展,并对当前存在的问题进行了讨论.  相似文献   
48.
Objective To report the presentation and treatment of traumatic elbow luxation and to evaluate success following closed or open reduction. Design Retrospective case series conducted between April 1999 and April 2009. Methods Records of 14 dogs and 11 cats were reviewed for signalment, history, radiographic findings and treatment; 14 owners were contacted via phone questionnaire to assess for limb function following treatment. Fisher's two‐tailed P test was used to evaluate potential risk factors for lameness. Results The majority of luxations were caused by car accident and 96% of the cases luxated in a lateral direction. Closed reduction was successful in all cats and 11 dogs; 3 dogs required open reduction. Owners rated the animals' limb function as excellent (71%), good (7%), fair (22%) or poor (0%). All cats were rated excellent. An excellent result following closed reduction was achieved in 67% of canine cases. All cases of open reduction achieved fair results. All owners were satisfied with the outcome. No risk factors were significantly associated with post‐reduction lameness. Conclusions Elbow joints with good stability following closed reduction have a favourable outcome. Poor stability following closed reduction is an indication for surgery. Results suggest that cats tolerate elbow luxation better than dogs.  相似文献   
49.
饲料安全隐患及对策   总被引:1,自引:0,他引:1  
饲料安全与食品安全密切相关.近年来,由饲料安全问题引发的食品安全事件屡见报道.笔者就影响饲料安全的主要问题进行了剖析,并提出改进措施.  相似文献   
50.
In the recent years, USUTU virus (USUV), a flavivirus of the Japanese encephalitis virus complex, has been reported in Central Europe. As part of a systematic surveillance programme to monitor possible entrance and/or circulation of vector-borne viruses, since 2001, sentinel-chicken flocks were placed throughout the Italian territory nearby areas considered at risk of virus introduction. They have been periodically checked for the presence of antibodies against flaviviruses by indirect ELISA, plaque reduction neutralization test for USUTU, West Nile and tick-borne encephalitis viruses. In July 2007, a sentinel chicken in a flock of 20 animals located within the Ravenna province seroconverted to USUV reaching neutralizing titres up to 1:5120. A second chicken seroconverted to the same virus 2 months later. Although no virus was rescued from these animals and from wild or farm birds sampled in the area, these results still provided evidence of the circulation of USUV in north-eastern Italy.  相似文献   
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