饲料酸化剂在防治动物疾病中的应用前景

饲料酸化剂，故名思义，是能酸化饲料的一类物质。可作为饲料酸化剂的物质很多，有天然的和人工合成的酸制剂，有无机酸和有机酸。单一的无机酸或有机酸，均各自具有其特定的优点和缺点，近年来，为克服单一使用的缺点，利用多种特定的有机酸和无机酸混合制成复合酸化剂，从而使饲料酸化剂的功能作用进一步优化和提高。最初，应用饲料酸化剂，往往仅作为改善饲料适口性的一种风味添加剂。随着科学进展，对各种动物消化道吸收功能的深入研究，饲料组分在动物消化系统中的代谢过程和消化道环境对动物生长的重大影响越来越详尽地被人们认识。添…     

青年獭兔消化能、粗蛋白水平研究

用 72只 10 0日龄左右青年獭兔进行能量、粗蛋白等营养需要量试验 ,设高能量高蛋白 (第 1组 :DE 11 17MJ/kg ,CP18 44 % )、高能量中蛋白 (第 2组 :DE 10 98MJ/kg ,CP 16 2 9% )、低能量高蛋白 (第 3组 :DE 10 5 3MJ/kg ,CP 19 2 9% )和低能量中蛋白 (第 4组 :DE 10 2 6MJ/kg ,CP 16 0 5 % ) 4个组。 74天生长发育和被毛质量测定结果 :①饲喂消化能为10 98～ 11 17MJ/kg的饲料 ,有利于青年獭兔生长速度和饲料利用率的提高 ,也有利于屠宰率的改善。其中以消化能为11 17MJ/kg、粗蛋白 19 2 9%的饲料 ,其生长速度和饲料利用率最好。②饲喂消化能为 10 2 6～ 10 5 3MJ/kg、粗蛋白16 0 5 %～ 19 2 9%的饲料 ,有利于毛皮质量的提高。③综合本研究结果 :生产优质商品兔皮的青年兔饲喂含消化能为10 2 6～ 10 5 3MJ/kg、粗蛋白 16 0 5 %～ 19 2 9%的饲料为宜。     

酸化剂在养鸡业中的应用及前景

预防疾病发生的一条重要措施就是确保饲料干净,尽可能不被病原菌污染。有机酸对大肠杆菌、沙门氏菌等有害微生物抑制作用效果良好,在饲料中添加有机酸,能够抑制饲料中大量有害微生物的生长,从而维持家禽消化道中微生物菌群的正常平衡,使得家禽的生产性能得到最大程度地提高。作为有机酸、无机酸制成的无毒无副作用的酸化剂,近年来国内外对其进行广泛性研究、制作,并作为添加剂应用来保护鸡群的胃肠健康,取得了良好的效果。1酸化剂的作用机理酸化剂的作用机理为:具有抑杀胃肠道有害细菌,促进有益菌生长、繁殖,降低病理性腹泻的发生率,降低胃…     

酸化剂在早期断奶仔猪日粮中的应用

自1963年《Nature》杂志报道在仔猪饲料中添加乳酸可以减少仔猪粪便中大肠杆菌的数量、提高生长速度后,人们对日粮酸化产生了极大兴趣,先后对一些酸化剂(包括无机酸、有机酸及其盐)的应用效果进行了大量研究。近年来,逐步转向酸化剂作用机理的研究(如对动物血液生化指标、消化酶活性、肠道微生物的影响等),并开展了与其它饲料添加剂(如寡糖、益生素、抗生素等)互作效应的研究。本文就早期断奶仔猪的消化生理与酸化日粮、酸化剂的应用现状及发展趋势等方面进行探讨。1早期断奶仔猪消化生理与酸化日粮1.1早期断奶仔猪的消化生理特点[1]仔猪在…     

不同饲粮结构及能量水平对后备特种野母猪生长性能的影响

通过调制不同的饲粮结构,探讨不同能量来源及水平对特种野母猪后备期生长性能的影响。选择玉米和以40%的稻谷代替部分玉米组成的能量饲料,能量水平依次为饲粮消化能12.00MJ/kg、12.50 MJ/kg、13.00 MJ/kg、13.50 MJ/kg。试验结果表明,利用玉米作为能量饲料在一定程度上可以提高猪只的生长速度。但利用40%稻谷替代部分玉米作为能量饲料可以显著降低特种野母猪的腹泻率、增强免疫力,提高猪的健康水平。     

酸化剂在母猪上应用的研究进展

酸化剂在畜禽生产中应用广泛,其主要作用是提高饲料蛋白质的利用率和改善肠道微生物菌群。酸化剂通过降低胃肠道pH,促进蛋白质变性、激活胃蛋白酶原提高动物对蛋白质的消化利用;有机酸通过进入微生物机体破坏细菌细胞的合成和繁殖,从而对胃肠道病原菌起到抑菌和杀菌作用。诸多研究表明,酸化剂在提高蛋白消化率和改善仔猪生产性能方面均有改善作用。目前酸化剂应用的相关研究中,其在母猪上的应用研究较少,本文对母猪的生理特点、酸化剂在母猪上应用的可能作用方式以及酸化剂在母猪饲粮中应用的作用效果进行综述,以期为酸化剂在母猪饲粮中的推广应用提供理论依据。     

饲用复合酸化剂的作用机理与应用实效

饲用复合酸化剂是新型生长促进剂,在动物保健和营养两方面都发挥重要作用。复合酸化剂对畜禽的良好作用,经多年的各地应用,已为广大养殖者所共识。用作饲料酸化剂的物质,有天然的,也有人工合成的;有无机酸也有有机酸。在生产上以往多用有机酸,因其具有良好的风味,能改善饲料的适口性,可直接进入动物体内参与新陈代谢,故有提高饲料品质和动物生长性能的作用,但成本较高。无机酸因其酸性强和成本低,且具有良好的加工性能所以也有应用。应用效果表明,使用单一酸化剂有其特定的优点和缺陷,若使用特殊配制的复合酸化剂,可达到有机…     

饲料酸化剂对畜禽保健作用的研究

1　酸化剂的种类和保健作用的机理1 .1　酸化剂的种类酸化剂分为单一酸化剂和复合酸化剂两大类。单一酸化剂包括有机酸和无机酸 ,饲料中常用的无机酸添加剂有盐酸、磷酸等 ,有机酸添加剂有柠檬酸、富马酸、乳酸、丙酸、苹果酸、山梨酸及其盐类。复合酸化剂是由不同种酸化剂或酸     

酸化剂的生物学功能及其在猪禽生产中的应用

酸化剂在动物肠道无残留、无耐药性且具有降低胃肠道pH、激活胃肠道消化酶、抑制有害细菌生长繁殖和作为肠道上皮细胞的能源物质等功能,是重要的“替抗”饲料添加剂之一,被广泛应用于养殖生产中。文章主要阐述酸化剂的种类及其在动物饲料与胃肠道中的作用机理,同时对酸化剂在猪禽生产中的应用进行综述,以期为养殖生产中合理使用酸化剂提供理论参考。     

肉仔鸡能量营养研究进展

1　肉用仔鸡的能量需要各国肉仔鸡能量需要标准不尽相同。我国肉用仔鸡饲养标准的日粮浓度比NRC低 1 0 %左右 ,见表 1。表 1　肉用仔鸡能量需要中国0～5周 5周以上NRC0～3周 3～ 6周 6～8周代谢能 (MJ/kg) 1 2 1 3 1 2 55 1 3 391 3 391 3 39　　注 :引自动物营养学 ,杨凤主编 ,1 991 ,农业出版社。吴成坤等 ( 1 980 )测定了 1～ 1 0周龄白洛克肉仔鸡的能量需要 ,对进食代谢能和增重能量进行回归分析 ,得出肉仔鸡的维持代谢能需要量为0 5 38MJ/kgW0 75。肉仔鸡增重代谢能需要量平均约为每千克增重 :1～ 4周龄 1 0 46MJ/kg ,5～ 1…     

商会自治的基石——商会自治规范研究

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。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

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.