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微生态制剂是指将动物体内正常的有益的微生物菌株经过特殊的加工制成的活菌制剂,一般用于畜牧业的饲料添加剂,还有小部分用于人类的消化器官疾病的治疗。从20世纪后半叶以来,水产养殖业中逐渐应用了许多微生态制剂,现在市场上主要用于虾的养殖和病害治疗的微生态制剂有光合细菌,酵母菌和芽孢杆菌类、益生素以及双歧杆菌制剂等。微生态制剂可以对虾养殖的环境进行改善,调节虾的生长质量,抑制虾体内的病原生长繁殖从而防止病害。 相似文献
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光合细菌与水产健康养殖 总被引:1,自引:0,他引:1
光合细蓖(PSB)是一种以光作能源并以二氧化碳或小分子有机物作碳源、以硫化氢等作供氢体,进行完全自养性或光能异养性生长但不产氧的一类微生物的总称,在自然界中分布极广,生命力极强.光合细菌无毒、无害,能被鱼体充分利用,对推动水产健康养殖具有重要意义. 相似文献
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微生态制剂在水产养殖中的作用机理及应用研究进展 总被引:9,自引:0,他引:9
介绍了微生态制剂在水产动物健康养殖中的作用机制,以及微生态制剂在刺参养殖中的应用前景。微生态制剂在水产动物中的作用机理包括通过竞争来抑制病原菌生长(如黏附位点、营养、能源等)、通过代谢物(如抑菌物质、消化酶等)调节微生态平衡、提高免疫机能、改善水质、群体感应(quorum sensing,QS)。刺参生理生化反应、生活习性的研究为刺参微生态制剂的开发奠定了基础,也存在一些问题限制了它在刺参养殖中的应用,但微生态制剂仍然是抗生素最有潜力的替代品,具有广阔的应用前景。 相似文献
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生物修复菌Rhodopseudomonas palustris的分离与培养特性研究 总被引:2,自引:0,他引:2
近年来,水产养殖病害频繁发生,水体富营养化,水产品失去固有的鲜味而带有土腥味,海洋赤潮多发,给水产养殖业造成严重损失。因此,水产养殖环境的净化已成为水产养殖业生产持续发展的关键技术,具有生物修复功能的光合细菌等菌种成为研究的热点。光合细菌是一种营养价值高且组分较全的微生物,广泛分布于海洋、湖泊、水田、污泥等处,能充分利用光能和各种有机物为其营养源,进行自身营养繁殖。光合细菌的菌体在生长繁殖过程中能利用有机酸、氨、硫化氢、烷类以及低分子有机物作为碳源和供氢体进行光合作用,同时降解和清除水体环境中的过量有机物… 相似文献
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本文综述微生态制剂的概念、作用机理、在水产养殖中的应用及微生态制剂的合理使用与注意事项.概括了水产微生态制剂具有抑制病原菌、刺激免疫系统、提高免疫力、提供营养、改善机体代谢、促进动物生长、改善水质的作用和功效.为水产微生态制剂的进一步研究提供了理论依据。 相似文献
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在刺参幼参培育水体中,定期加入由乳酸杆菌、海洋红酵母、芽孢杆菌、光合细菌4种微生态制剂按不同比例复合成的复合微生态制剂,通过测定幼参培育水体中的p H、化学需氧量(COD)、氨态氮、亚硝酸态氮、活性磷等水质指标和幼参的生长指标,探讨微生态制剂对幼参培育水体氨氮等水质变化的影响以及对幼参生长的影响。结果表明:在幼参培育水体中加入一定配比乳酸杆菌、海洋红酵母、芽孢杆菌和光合细菌,在一定程度上能降低水体中的氨态氮、亚硝酸态氮等有害物质。其中试验Ⅴ组(按配方5添加)对养殖水体中氨态氮、亚硝酸态氮等物质的调节作用和对幼参生长的促进作用最显著(P0.05)。 相似文献
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浅析水产养殖中的有益菌与生态防治 总被引:2,自引:0,他引:2
论述了水体生态平衡在水产养殖中的重要意义;微生物生态在水体生态平衡中的作用,与微生态的关系;生态防治的特点,微生物生态与微生态制剂在水产养殖中应用情况,有益菌与益生菌问题等。 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