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蝗虫的俗名又叫蚂蚱,是危害草地的重要害虫。按生活习性蝗虫分两类:一类是具有成群远距离迁飞习性的大型蝗虫叫飞蝗;第二类是只能近距离迁移的中小型蝗虫叫土蝗。1 发生情况 辽宁省发生的主要蝗虫种类有东亚飞蝗、小车蝗、短星翅蝗和长翅燕蝗等。1998年以来,辽宁省以土蝗为主,年草地蝗虫发生面积13.3-36万hm2,平均虫口密度15-56只/m2,最高达1400只/m2。2001年是自建国以来东亚飞蝗首次在辽宁发生的1年,发生面积 相似文献
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中国奶牛之乡——安达市地处松嫩平原腹地，黑龙江省中西部。全市奶牛存栏 95 540头，拥有草原 251万亩。由于今年气候变化，长期干旱致使草原蝗灾比较严重，发生面积在 70万亩左右，严重制约了草地畜牧业的发展。为此，我们在草原蝗虫发生严重地段进行了牧鸡灭蝗工作，实践证明，牧鸡灭蝗投入低、效益高，灭蝗效果显著。 1蝗灾情况 根据往年蝗虫危害牧草的程度， 5月初对全市的人工草场和天然草场进行了挖虫卵的调查，从挖虫卵的情况看，该市任民、升平、中本镇的 3.5万亩草原虫卵较多，每平方米平均有 400～ 500粒虫卵， 6月初对三个… 相似文献
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青海四种土蝗(直翅目:斑翅蝗科)染色体核型分析 总被引：1，自引：0，他引：1
严林 《青海畜牧兽医杂志》2002,32(4):5-7
用常规染色体制片方法研究了青海高山草地的四种土蝗：黄胫异痂蝗（Bryodemella bolderei holdereri Krauss,)、白边痂蝗（Bryodema luctuosum luctuosun Stoll)，黄胫小车蝗（Oedaleus infernalis Sauss）、亚洲小车蝗（Oedaleu asiatisc B.-Bienko）的染色体数目和核型。四种土蝗染色体数目均为，（2n♂）＝23＝27＝22＋XO；全部染色体都为近端着丝点类型；四种土蝗染色体的核型公式均为K(2n,♂）＝23＝23T＝4L＋14M＋4S＋XO。结果表明，斑翅蝗科3属间的蝗虫主要区别为常染色体和性染色体相对长度有明显差异，小车蝗属内2种间区别主要为常染色体相对长度的差异。 相似文献
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塔城地区总面积10.45万km~2,约占全疆总面积的6.5%。现有草场总面积703.4hm~2,其中可利用面积572hm~2,由于草场面积大,类型多,历来是新疆蝗虫高发地区之一。为此自2000年起,塔城地区的草原工作者以"保护草原生态环境、增加农牧民收入,实现生态、经济、社会效益三赢"的思路和目的,致力于草原牧鸡治理草原蝗虫灾害的推广工作,经过多年推广牧鸡治蝗工作得出结论,一是控制草原蝗害,免去农药对草原带来的负面影响;二是为当地农户增加收入;三是为各级政府节省大量药物治蝗开支,集 相似文献
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近几年来,由于受气候条件和周边地区蝗灾的影响,辽宁省一些地区的草场、农田多次遭受蝗虫侵害,且有逐年加重发生的趋势。蝗虫种类除本地土蝗(黄颈小车蝗、星翅蝗等)外,首次出现了东亚飞蝗,密度均在每平方米30～100只,最高达到每平方米2000只以上。草地蝗虫来势猛、蔓延快,在很短时间内迅速扩散,所到之处牧草被啃食殆尽,给农牧业生产造成不可估量的损失。因此,预测和防治虫害已成为各省畜牧业生产不可忽视的一个问题。针对本省草地蝗虫发生特点及造成的危害,省政府和地方政府高度重视,仅2001年省政府就动用省长预备金600万元用于草地灭蝗。各… 相似文献
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渭源县黄香沟牧区气候湿润，草地资源丰富，是县内主要牧区。近年来受蝗虫危害，牧区草原退化，2010年开始，渭源县采用牧鸡灭蝗技术，经试用推广，牧鸡灭蝗具有“灭效高、见效快、无公害、收益好”等特点，逐步发展为草原保护，维护生态平衡，促进畜牧业发展的一项有重要措施。 相似文献
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塔城地区总面积10.45万km2,约占全疆总面积的6. 5%.现有草场总面积703.4hm2,其中可利用面积572hm2,由于草场面积大,类型多,历来是新疆蝗虫高发地区之一.为此自2000年起,塔城地区的草原工作者以"保护草原生态环境、增加农牧民收入,实现生态、经济、社会效益三赢"的思路和目的,致力于草原牧鸡治理草原蝗虫灾害的推广工作,经过多年推广牧鸡治蝗工作得出结论,一可控制草原蝗害,免去农药对草原带来的负面影响,二可为当地农户增加收入,三可为各级政府节省大量药物治蝗开支,集生态、经济、社会效益于一体,是实现草原蝗虫可持续治理的根本途径之一,具有广阔的推广应用前景和市场前景. 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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以国际标准强毒Ｒ株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离ＭＧ,并收集感染鸡所产蛋分离ＭＧ。结果表明,人工感染４８小时后上、下呼吸道及肺已被全面感染,９６小时气囊已被感染,１２０小时输卵管已能分离到ＭＧ,卵巢始终分离不到ＭＧ。人工感染鸡自１４４小时便能在其所产蛋中分离出ＭＧ。药物治疗能在７２小时内消除感染,油乳剂苗则需２４天后逐渐降低蛋内ＭＧ分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内ＭＧ,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献