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1饲料粉碎粒度控制
粉碎粒度的大小直接影响动物的消化吸收和饲料后续加工工序及产品质量。控制好物料的粉碎粒度是饲料生产的关键环节。合适的粉碎粒度对饲料营养价值和其他品质的贡献主要表现在增加动物肠道消化酶或微生物作用的机会,提高饲料的消化利用率, 相似文献
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饲料粉碎粒度对饲料品质的影响 总被引:3,自引:0,他引:3
粉碎是饲料加工过程中必不可少的一个重要环节,也是提高畜禽对饲料消化利用率的一个有效途径。其目的和作用:一是提高物料的利用价值;二是提高饲料产品的加工质量。粉碎工艺是饲料加工过程中提高饲料质量的重要环节,是使饲料得到合理利用的必要手段之一。粉碎粒度的大小应根据原料种类、饲喂动物的种类、生长阶段 相似文献
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调质是对颗粒饲料制粒前的粉状物料进行水热处理的一道加工工序,国内外研究表明调质是影响颗粒饲料质量的重要因素之一,它在颗粒饲料总体质量中所起的作用为20%左右。随着市场对颗粒饲料品质要求的提高,各饲料加工企业也越来越重视饲料加工中的调质工序,改进或升级调质设备是他们当前改善颗粒饲料产品质量、提高市场竞争力的重要手段之一。1调质器在颗粒饲料加工中的作用1.1对粉状物料作熟化处理。大多数动物消化淀粉的能力很低,但能较大程度地消化熟淀粉,调质器使物料在水热作用下,淀粉的糊化度大幅度增加,同时还促进物料中的蛋白质受热变… 相似文献
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粉碎工艺对饲料加工和营养价值及对动物生产性能的影响 总被引:4,自引:0,他引:4
粉碎是饲料生产7大工序(原料接受、清理、粉碎、配料、混合、成形及计量打包)中重要的环节之一。一般饲料中需粉碎的原料占配方比例的50%~80%,粉碎工序的电耗占饲料厂生产车间总电耗的30%~70%。谷物经粉碎后,表面积增大,与肠道消化酶或微生物作用的机会增加,消化利用率提高;粉碎使配方中各组分均匀的混合,减少了混合后的自动分级,可提高饲料的调质与制粒效果以及适口性等。粉碎工艺中的重要指标是原料粉碎的粒度、粒度的均匀性、粉碎产量和加工电耗等。这些指标对饲料加工生产性能、饲料营养价值和动物的生产性能均… 相似文献
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饲料是畜禽生产上开支最大的一项,在我国饲料支出约占总成本的65%70%,通过恰当的加工方法可以获得较好的经济效益。饲料加工的目的正是为了充分发挥饲料营养价值的潜力,提高产品质量和饲养效果。饲料加工对动物营养的影响一直是饲料加工工艺学家和动物营养学家关心的问题,将加工工艺学和动物营养学有机结合起来能够更大提高禽生产性能。1粉碎粉碎,是饲料加工中的标准,粉碎的主要目的是增加饲料接触消化酶的表面积,以使之更易于消化,这也是饲料搅拌、制粒和接受其它处理所必需的。目前许多研究结果表明:粉碎对禽生产性能有明… 相似文献
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加工工艺对饲料营养价值及动物生产性能的影响 总被引:10,自引:1,他引:9
饲料是畜禽生产上开支最大的一项,在我国饲料支出约占总成本的65%~70%,通过恰当的加工方法可以获得较好的经济效益。饲料加工的目的正是为了充分发挥饲料营养价值的潜力,提高产品质量和饲养效果。饲料加工对动物营养的影响一直是饲料加工工艺学家和动物营养学家关心的问题,将加工工艺学和动物营养学有机结合起来能够更大提高动物生产性能。1粉碎粉碎的主要目的是增加饲料接触消化酶的表面积,以使之更易于消化,这也是饲料搅拌、制粒和接受其它处理所必需的。目前许多研究结果表明:粉碎对饲料营养价值和畜禽的生产性能有明显的… 相似文献
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饲料原料的粉碎是饲料加工中非常重要的环节,通过粉碎可增大单位质量原料颗粒的总表面积,增加饲料养分在动物消化液中的溶解度,提高动物的消化率。我国每年粉碎加工总量达2亿多吨。饲料粉碎机作为饲料工业的主要装备,对饲料质量、饲料报酬、饲料加工成本的形成是一个重要因素。所以,恰当地掌握粉碎技术,选用适当的粉碎机型是饲料生产不可忽视的问题。 相似文献
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粉碎机是决定饲料粉碎质量的设备,锤片和筛片是主要工作件,对粉碎的颗粒产生重要影响,锤片的线速度、数量和截面以及筛片的尺寸和厚度、筛孔的比例都将是影响粒度的参数。 根据饲喂动物的不同,要求粉碎后的物料粒径也不同。锤片状态对物料粉碎质量有很大影响,比如磨掉棱角的锤片与新锤片相比,其加工物料的细度有很大不同,饲料粒度的突然变化,会使蛋鸡产生应激反应,影响产蛋率。为 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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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
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献