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随着现代养殖业规模化和专业化的发展,畜禽感染各种疾病的危险性大大增加。为了预防畜禽疾病、促进动物生长发育、提高饲料转化效率及经济效益,多种抗生素药物用作饲料添加剂。抗生素添加剂的应用曾创造了养殖业和饲料工业的革命,规模养殖在全世界得到了迅速发展,动物的生产数量得到了大幅度的提高。 但是,饲料中长期使用抗生素类药物添加剂所产生的负面效益也日益明显地暴露出来。主要表现在:引起病原微生物产生抗药性;破坏动物体内正常菌群的生态平衡;降低机体免疫功能及畜禽产品中的药残直接危害人体健 相似文献
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饲料中抗生素与益生素的联合应用初探 总被引：2，自引：0，他引：2
1929年英国的Fleming发现抗生素以来熏给人类生产和生活带来了巨大变化熏同时在畜牧业和饲料工业生产当中熏抗生素也得到了极其广泛的应用熏多种抗生素等作为生长促进剂在全世界被普遍用作饲料添加剂熏以提高动物的生产性能、预防动物疾病的发生等。随着抗生素的滥用熏其各种弊端也日益暴露出来,如造成动物正常菌群失调,产生耐药菌株,大量药物残留、污染环境等,对人类健康造成了严重威胁。一方面消费者要求禁止滥用抗生素作为饲料添加剂,另一方面要加大抗生素替代品研制开发力度。在二十世纪六七十年代人类发现抗生素的种种弊端后,益生素作… 相似文献
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导读：随着饲料工业发展,饲料添加剂在我国得到了迅速地应用和推广,添加剂的种类在增加,其作用也不仅仅是促进生长,一些添加剂已成为促进营养物质消化吸收或保证动物营养生理功能正常发挥所必需的物质,成为全价饲粮中必不可少的组成部分。但是,有些饲料添加剂使用不当或过量也会对动物和人体健康及生态环境产生不良影响。比如抗生素添加剂具有刺激动物生长、提高动物增重速率、改善动物对饲料的利用效率、防治畜禽疾病、保障动物健康生长等作用。但是,专家们认为长期食用有抗生素残留的食品,会降低人体的免疫力。由于抗生素的“三致”作用,易产生耐药性,并降低人体免疫力。因此,抗生素已被称为“人类健康的超级隐形杀手”。 相似文献
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《中国畜牧兽医文摘》2012,(6)
<正>抗生素作为饲料添加剂在全球范围内应用已有50多年的应用历史。但抗生素的滥用,导致了耐药菌株的产生,给人类和动物健康带来极大的危害。近年来,导致人类和动物感染耐药菌的问题愈显突出。有些病原菌的抗药性问题之严重,以至于针对该病 相似文献
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酸化剂对蛋鸡饲粮利用率和血液指标的影响 总被引：2，自引：0，他引：2
近年来,我国养殖业得到了迅速发展,动物疾病的发生也比较多.饲料中添加抗生素在预防疾病、促生长和提高饲料报酬等方面发挥了积极的作用.但抗生素的长期使用却导致了动物抗药性的产生,畜产品中残留的药物也影响到人类的健康.因此,无毒,无不良反应的饲料添加剂越来越受到人们的青睐. 相似文献
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《北方牧业》2006,(13)
<正> 在畜牧生产中,提高养殖经济效益,首先要防止疫病的发生,其次是提高饲料转化率、缩短饲养周期。人们为了预防疫病,除了正常的疫苗预防外,还不间断地在饲料中添加抗生素。抗生素的大量使用,甚至滥用,会导致耐药菌株的产生以及动物食品中的药物残留,直接或间接给人类健康造成危害。同时,抗生素的长期使用还会使动物体内的免疫系统产生依赖性,使动物自身的免疫能力下降,从而导致抗应激能力下降。近些年来,许多发达国家已纷纷采取措施来禁止抗生素在饲料中的滥用;人们为了提高畜禽的生产性能,除了进行品种的改良外,还在饲料中大量的使用了各种人工合成的以促长为目的的药源性饲料添加剂,现在人们已经发现过去曾经使用过的添加剂的残留是对人体有相当危害的,如:盐酸克仑特罗、喹乙醇等。另外,由于饲料中促长剂的应用及营养成分的全面与均衡,使得动物的生产性能得到大幅提高,但同时却打破了动物体内各系统的平衡关系,使所生产的畜禽产品品质降低。中草药属纯天然物质,有促进动 相似文献
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20世纪40年代以来,在养殖业和饲料工业的发展过程中,养殖户为促进动物的生产性能,追求利益最大化,大量滥用各种激素、防病促生长的化学药物、抗生素等饲料添加剂,致使动物性产品质量的下降和动物对药物耐药性的产生,最终给人类的健康带来了极大危害。如今,激素的禁用、抗生素的限用、饲料资源的短缺,使得动物性产品数量和质量的 相似文献
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随着现代饲料工业的快速发展,大量人工合成的饲料添加剂如抗生素、促长素、驱虫剂、激素、调味剂、改良剂、防腐剂在饲料中普遍添加。这些添加剂的应用,对畜牧业无疑起到了巨大的推动作用,但是随着研究的不断深入及生产中出现的问题,人们已经逐渐认识到了这些添加剂带来的负面效应。特别是抗生素的大量使用,导致产生的耐药性和残留以及给人和动物健康 相似文献
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随着饲料工业的快速发展,大量人工合成的饲料添加剂如抗生素、促长素、驱虫剂、激素、调味剂和改良剂、防腐剂等在饲料中普遍添加。这些添加剂的应用,对畜牧业发展起到了巨大的推动作用,但是也带来了负面效应。特别是抗生素的大量使用,产生的耐药性和残留给人类健康带来了危害,已经引起了广大科技工作者和消费者的关注和忧虑,现在有些国家和地区已经用立法形式禁止或限制在饲料中添加抗生素。在发达国家,发展天然物饲料添加剂,已是大势所趋。 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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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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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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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