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外翻肠囊法的应用研究 总被引：2，自引：0，他引：2
外翻肠囊法是在体外培养小肠肠环技术和刷状缘膜囊技术的基础上发展而来的.外翻肠囊法是指在动物麻醉无痛或屠宰状态下立即分离小肠,去掉肠系膜,用生理盐水或缓冲液冲洗干净,然后根据试验目的将所需肠段分割为若干小段,外翻使肠黏膜向外,结扎一端形成肠囊状,灌注人工培养液后结扎另一端,置于添加有被测物质的培养液中,通入95 %氧气和5 %二氧化碳的混合气体,培养一定时间后,根据囊内外被测物质的变化来反应肠道对物质吸收状况的一种生理学试验方法. 相似文献
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仔猪小肠对二肽吸收特点的研究 总被引：15，自引：1，他引：14
本试验采用体外外翻肠囊的方法研究了等摩尔浓度的Ｌ 甘氨酸 Ｌ赖氨酸组成的二肽（Ｇｌｙ－Ｌｙｓ）和游离甘氨酸和赖氨酸混合物（Ｇｌｙ＋Ｌｙｓ）在仔猪小肠各段的吸收特点。将仔猪小肠划分为空肠前段、中段、后段和回肠段,分别在各段设置了两个不同的培养液处理组,分别是浓度为２０ｍｍｏｌ／Ｌ的Ｇｌｙ－Ｌｙｓ和Ｇｌｙ＋Ｌｙｓ混合物培养液组。每个处理３个重复（回肠段无重复）,每个重复为一个外翻肠囊,将每个外翻肠囊置１０ｍｌ培养液中培养１５分钟。旨在比较：体外培养１５分钟后,同一浓度下的Ｇｌｙ－Ｌｙｓ和Ｇｌｙ＋Ｌｙｓ在外翻肠囊各部位的吸收差别,从而确定Ｇｌｙ－Ｌｙｓ在仔猪各肠段的吸收特点。结果表明,同等摩尔浓度下,Ｇｌｙ－Ｌｙｓ组中的赖氨酸和甘氨酸在仔猪空肠中段肠组织的累积量显著大于Ｇｌｙ＋Ｌｙｓ组;从肠囊在１５分钟培养后总的氨基酸摄入量上看,Ｇｌｙ－Ｌｙｓ组的赖氨酸和甘氨酸在空肠中段高于Ｇｌｙ＋Ｌｙｓ组,且二者在赖氨酸上的差异显著。这说明,二肽中甘氨酸和赖氨酸至少在空肠中段的运输系统有别于游离态的甘氨酸和赖氨酸,且对二肽的运输显得比对游离氨基酸的运载更有效。 相似文献
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培养液磷含量和pH值对鸡离体小肠磷吸收的影响 总被引：1，自引：0，他引：1
本研究主要探讨了培养液不同pH值和磷含量对鸡离体小肠磷吸收的影响,为体外培养鸡小肠合理选择培养液pH值和用外翻肠囊法评定饲料有效磷时合理选择培养液磷浓度提供参考依据。采用2个单因子随机试验,每个因子4个处理。48只30日龄体重相近的三黄肉公鸡的十二指肠、空肠和回肠肠囊随机分配到8个处理中,每个处理6个重复,每个重复1个肠囊,39℃培养50min。结果表明：pH5．0～7．0时,肠囊的磷吸收量线性增加;pH8．0时,肠囊的磷吸收量降低;与pH5．0比较,pH7．0时,肠囊的磷吸收量极显著增加（P〈0．01）。培养液磷含量在50～200μg／mL时,肠囊的磷吸收量与磷含量呈正相关;当磷含量增加到400μg／mL,十二指肠肠囊和空肠肠囊的磷吸收量开始降低;磷吸收率与培养液磷含量之间呈负相关,不同处理之间差异极显著（P〈0．01）。结果显示：以肉仔鸡为动物模型,用外翻肠囊法评定饲料有效磷时,培养液适宜pH为6．0～7．0;有效磷含量不能超过200μg／mL,以50μg／mL左右为宜。 相似文献
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用外翻肠囊法研究有机锰在肉仔鸡小肠中的吸收特点 总被引：8，自引：0，他引：8
用外翻肠囊法研究肉仔鸡十二指肠、空肠和回肠对无机锰和有机锰的吸收特点。共包括2个试验，试验1是以硫酸锰为锰源，根据单位时间锰的吸收率与外翻肠囊培养时间的曲线关系确定最佳培养时间，试验2是在此培养时间下比较不同形态锰在肉仔鸡小肠中的吸收特点。2个试验均采用单因子完全随机设计。试验1培养时间分别为20、40、60和80min 4个处理组，将48只28日龄商品代AA肉公鸡随机分到4个处理组，每组6个重复，每个重复2只鸡(为了扣除内源影响，其中1只鸡作为零添加锰水平处理)，每只鸡的十二指肠、空肠和回肠分别用作相应部位肠段外翻肠囊的1个重复。在试验2中共设8个处理组，分别为：硫酸锰、甘氨酸锰螫合物、蛋氨酸锰螫合物、弱络合强度的蛋氨酸锰(Mn—Met E)、中等络合强度的氨基酸锰(Mn—AA A)和强络合强度的氨基酸锰(Mn—AA B)、硫酸锰与甘氨酸混合物及硫酸锰与蛋氨酸混合物的处理组。为了扣除内源影响，另设1组作为零添加锰水平处理。用于试验1中日龄相同的AA肉公鸡72只，随机分到9个处理组，每组8个重复，每个重复1只鸡，每只鸡的十二指肠、空肠和回肠分别用作相应部位肠段外翻肠囊的1个重复。结果表明：(1)锰的吸收率和培养时间在40min内呈线性关系，因此选择30min为试验2的培养时间；(2)体外培养回肠肠囊对无机锰的吸收率一般是十二指肠和空肠肠囊的2～6倍；(3)回肠中锰的吸收率受到添加锰源的显著影响，其中合成蛋氨酸锰组锰的吸收率明显高于硫酸锰和合成甘氨酸锰，中等和强络合强度的氨基酸锰组锰的吸收率也明显高于无机锰和合成甘氨酸锰。试验结果提示，在体外简单缓冲溶液培养的肉仔鸡小肠各段外翻肠囊中，回肠是肉仔鸡小肠吸收锰的主要部位；络合或螫合的有机态锰在体外培养的小肠外翻肠囊中的吸收率比无机形态的锰高；作为配体而言，蛋氨酸比甘氨酸更有利于促进锰的吸收。 相似文献
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本试验用外翻肠囊法研究高钙对肉仔鸡不同肠段(十二指肠、空肠和回肠)吸收不同形态锰的影响,以比较有机锰和无机锰在高钙条件下吸收特点的差异。采用单因子完全随机设计,培养液中添加的4种锰源分别为:硫酸锰、弱络合强度的蛋氨酸锰(Mn-MetE)、中等络合强度的氨基酸锰(Mn-AAA)和强络合强度的氨基酸锰(Mn-AAB)。为了扣除内源的影响,设置1个零添加锰水平处理。将40只31日龄AA肉公鸡随机分到以上5个组,每组8个重复,每个重复1只鸡,每只鸡的十二指肠、空肠和回肠分别作为相应肠段外翻肠囊的一个重复。结果表明:1)体外培养回肠肠囊对锰的吸收率显著高于十二指肠(P<0.01);2)回肠肠囊对强络合强度的Mn-AAB中锰的吸收率显著高于硫酸锰或中等络合强度的Mn-AAA(P<0.05)。本试验结果表明:在高钙条件下,络合形态的有机锰在体外培养的肉仔鸡肠囊中的吸收率显著高于无机形态的锰;强络合强度有机锰源中的锰能更强地抵抗小肠内的解离,比弱或中等络合强度的有机锰源更有利于锰的吸收。 相似文献
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为研究深海鱼肽对肉仔鸡肠道氨基酸(苏氨酸、甘氨酸、脯氨酸、异亮氨酸、亮氨酸、组氨酸、赖氨酸)吸收的影响,选取健康体重差异不显著的6周龄爱拔益加肉仔公鸡10只,随机分为两个处理,分别是深海鱼肽处理组和游离氨基酸处理组,每个处理5个重复.采用外翻肠囊法,将肠段进行离体培养.结果显示:在深海鱼肽系统中,7种氨基酸回肠中的总吸收高于游离氨基酸系统;对苏氨酸、甘氨酸、脯氨酸、组氨酸,深海鱼肽能很好的促进它们在小肠的吸收,且在小肠后段效果更明显;深海鱼肽系统中异亮氨酸、亮氨酸、赖氨酸的吸收相对于游离氨基酸系统要低.结果表明,深海鱼肽对不同肠段不同氨基酸作用效果不同. 相似文献
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通过研究探讨不同培养温度对鸡离体小肠磷吸收和肠黏膜细胞活性的影响,旨在为鸡小肠离体培养温度的合理选择提供参考依据。采用单因子随机试验,选用24只35日龄体重相近的三黄肉公鸡,取十二指肠、空肠和回肠肠囊,分别随机分配到4个处理中,每个处理6个重复,每个重复1个肠囊,分别在30、34、38和42℃条件下水浴振荡培养50min。结果表明:培养温度在30～38℃时,肠囊磷吸收量与温度呈正相关,38℃时肠囊的磷吸收量显著高于30℃和34℃时肠囊的磷吸收量(P<0.05),42℃时,肠囊的磷吸收量极显著降低(P<0.01);培养液中LDH活性与培养温度呈线性关系,培养温度在30～38℃时,培养液中LDH活性部分有显著差异(P<0.05),42℃时培养液中LDH活性极显著高于其它处理(P<0.01)。结果提示:鸡离体小肠适宜的培养温度是38℃。 相似文献
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本试验采用离体外翻肠囊法研究了蛋鸡小肠对Gly-L-Leu肽的吸收和转运.将6只206日龄的海兰褐蛋鸡的小肠分割为十二指肠、空肠前、中、后段和回肠5段,分别制备外翻肠囊.每3只鸡的肠囊为1个试验组,将灌注浆膜液(含Ca2+/Mg2+PBS缓冲液)的各肠囊置于相同的二肽培养液(含20mmoL/LGly-L-Leu的Ca2+/Mg2+PBS缓冲液)中进行培养.试验1组培养液添加了肽酶抑制剂(10μmoL/L Bestatin和Amastatin),试验2组浆膜液添加了等量的肽酶抑制剂.培养15分钟后测定培养液、浆膜液、肠组织匀浆液中二肽和游离氨基酸的含量.结果表明,鸡十二指肠、空肠前、中段对Gly-L-Leu有强烈的水解作用,空肠后段和回肠的水解能力相对较弱.鸡各肠段均能迅速吸收Gly-L-Leu,并将其转运到浆膜液中.吸收量和转运量有沿肠道延伸而增强的趋势. 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
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献