溶菌酶在饲料中的应用

正溶菌酶(Lysozyme)又称胞壁质酶或N-乙酰胞质聚糖水解酶,是动物体内一种非特异性免疫因子,具有抗菌消炎、抗病毒、增强免疫力、促进双歧杆菌等有益菌增殖的作用。本文介绍了溶菌酶的特性、分类,重点综述了溶菌酶作为饲料添加剂在猪、鸡、鸭以及反刍动物等饲料中的应用。1溶菌酶的特性溶菌酶,又称胞壁质酶或N-乙酰胞壁质聚糖水解酶,能水解肽聚糖中的N-乙酰葡萄糖和N-乙酰胞壁酸之间的β-1,4糖苷键,以此破坏细菌的细胞壁,具有较强的抑菌抗菌活性。溶菌酶是一种白色、微白色结晶型或无定型粉末,无臭、味甜且易溶于     

牦牛胃溶菌酶抗小鼠腹泻的研究

本研究采用PichiaPinkTM毕赤酵母表达系统对牦牛胃溶菌酶进行异源表达,以探索提高重组牦牛胃溶菌酶表达量的方法以及重组牦牛胃溶菌酶对大肠杆菌O111所致小鼠腹泻的治疗作用。试验选取10只体重相近的无特定病原体昆明小鼠,用大肠杆菌O111建立小鼠腹泻模型;建模成功后取30只小鼠随机分为6组,每组5只,设对照组、腹泻模型组、牦牛胃溶菌酶组、重组牦牛胃溶菌酶组、抗生素治疗组、溶菌酶产品治疗组,除对照组和腹泻模型组外其余各组灌胃给药,记录小鼠采食量及体重;第4天采血后全部扑杀,取小鼠十二指肠组织制切片做形态学观察;取肠道内容物进行肠道菌群Alpha和Beta多样性分析。结果表明：重组牦牛胃溶菌酶在诱导96 h时表达量最高,分子质量约为15.6 ku,比活性为1 428.58 U/mg。攻毒后腹泻模型组、溶菌酶产品治疗组与对照组相比采食量显著降低（P<0.05）;腹泻模型组与对照组相比,白细胞数、淋巴细胞数和中性粒细胞数均有极显著升高（P<0.01）;十二指肠病理解剖观察发现,牦牛胃溶菌酶组肠道绒毛有所增长且厚度增加;重组牦牛胃溶菌酶组肠绒毛有所恢复。Alpha多样性分析发现,...     

发酵活性剂黄储饲草育肥肉牛试验效果

反刍动物利用其庞大的瘤胃微生物(每克胃内容物含210～430万个)如纤毛虫、细菌等,以及这些微生物分泌的纤维素酶,淀粉酶等活性物质能将其反刍动物摄人的大量粗纤维素、木质素分解成纤维二糖、葡萄糖,最终产生乙酸、丙酸、丁酸等挥发性脂肪酸,连同这些微生物被反刍动物以菌体蛋白形式吸收利用,形成了反刍动物吃的是草,生产的是乳、肉、毛等高蛋白畜产品的复杂生产过程.     

反刍动物前胃疾病诊治技术探讨

前胃疾病是反刍动物最为普遍、发病率较高的一种疾病,前胃疾病对反刍动物养殖业危害最为普遍和严重。文章结合作者长期在大型奶牛场和基层兽医站从事奶牛和水牛、黄牛、山羊、绵羊等反刍动物的疾病诊治,现就反刍动物前胃疾病的诊治技术进行简述。     

反刍兽几种常见前胃疾病的鉴别诊断

<正>反刍动物前胃疾病是最常见的病,也是多发病,为了解反刍动物前胃疾病的发生原因及其防治方法,首先必须了解反刍动物的前胃形态以及与临床有关的几个问题。反刍动物的胃是复室胃,由瘤胃、网胃、瓣胃和皱胃四个部分组成,前三个部分因为没有腺体不能分泌胃液,称其为前胃,皱胃有腺体,分泌胃液。瘤胃最大占全胃的80%,皱胃最小仅占5%。反刍动物的前胃有一个微生物群系,其独特的生理作用受前胃的内环境所影响,如瘤胃内的温度、pH值以及菌群平衡等。     

反刍动物的营养代谢特性

正反刍动物营养学是动物营养学的重要分支,研究反刍动物营养物质摄入、消化代谢和转化利用与生产和生命活动相互关系对饲养反刍动物意义十分重大。用单胃动物的营养观点指导反刍动物的饲养,难免造成饲养管理不当。反刍动物具有四个胃,依次为瘤胃、网胃(蜂窝胃)、瓣胃和皱胃(真胃)。前三个称谓前胃,皱胃相当于单胃动物的胃,具有胃腺。前胃的一部分则不具有胃腺,前两个胃室(瘤胃和网胃)将食物软化,特别是利用共     

瘤胃酸中毒的救治

瘤胃酸中毒主要是过食碳水化合物精料、酸度较高的青贮饲料、糖类多汁饲料致使瘤胃内发生伴有显著的乳酸异常发酵,乳酸大量产生并在瘤胃内过度积聚使胃内微生物群落活性降低,引起前胃机能障碍,导致全身中毒为主要症状的反刍动物疾病。     

乐至黑山羊肾溶菌酶基因克隆及原核表达

本研究对乐至黑山羊肾溶菌酶(LZLyK)基因进行了克隆、表达,并对其活性进行了测定。采用比较基因组技术,成功克隆了LZLyK基因,其cDNA长444 bp,编码147个氨基酸。同源性分析结果表明,氨基酸同源性与绵羊溶菌酶2(M32498.1)最高,达96.9%。构建原核表达质粒pET- LZLyK,转化大肠杆菌BL21(DE3)并诱导表达。SDS-PAGE分析结果表明,重组蛋白LZLyK得到正确表达,分子质量约为16、30 ku。采用比浊法测定了LZLyK蛋白的活性,其活性为15 U/mL,表明LZLyK蛋白具有一定抗菌活性。运用实时荧光定量PCR发现在乐至黑山羊肝脏、肾脏、气管和皱胃中均有肾溶菌酶基因的表达,在胃中表达量较高。     

奶牛常见前胃疾病的防治

<正>前胃疾病是指反刍动物的前三胃(瘤胃、网胃、瓣胃)发生的病变,在反刍动物中前三胃无腺体,主要起贮存食物和发酵分解粗纤维的作用。笔者着重对奶牛前胃常见疾病的防治进行了讨论。     

泌乳奶牛的维生素一矿物质添加剂

<正> 单胃动物与反刍动物对活性物质的要求是有差别的,一般情况日粮中的天然饲料中就能满足反刍动物的要求。但是,近年来日粮中的主要饲料的化学成分出现了相当大的变化,其原因是往土壤里施用高剂量的无机肥料,特别含氮物质和应用人工降雨灌溉,     

藏绵羊溶菌酶1基因的克隆、原核表达及生物信息学分析

试验旨在研究藏绵羊溶菌酶(lysozyme,LZM)1基因在瘤胃、瓣胃、皱胃、气管、肝脏和肾脏各组织中的表达情况、进化关系及抑菌活性.采用RT-PCR技术克隆藏绵羊LZM1基因,定量PCR检测LZM1基因在瘤胃、瓣胃、皱胃、气管、肝脏和肾脏中的表达情况,并将该基因的氨基酸序列与普通牛胃LZM等氨基酸序列进行比对,根据邻位连接法构建系统进化树;将该基因插入pET-32a质粒后构建得到pET-32a-LZM1重组质粒,转化大肠杆菌BL21(DE3)感受态细胞并诱导表达,SDS-PAGE法鉴定表达产物;采用比浊法测定LZM1蛋白的活性;采用琼脂糖平板扩散法研究异源表达蛋白的抑菌活性.结果表明,从藏绵羊瘤胃、瓣胃、皱胃、气管、肝脏和肾脏各组织中成功克隆藏绵羊LZM1基因,其在瘤胃、瓣胃、皱胃、气管、肝脏和肾脏中均有表达,在皱胃中表达量最高;其氨基酸序列与普通牛胃LZM(GenBank登录号:NM_001080339.1)序列的同源性最高(96%);重组蛋白LZM1分子质量约为35 ku;其比活力约为400 U/mL;该重组LZM1对金黄色葡萄球具有良好的抑菌活性.     

The role of lysozyme in killing and lysis of coliform bacteria in the bovine animal 2. Effect of absorbing serum with bentonite or bacteria

Adding lysozyme in the presence of EDTA to bentonite-absorbed serum produced variable results in bacteriolytic tests either restoring lytic activity, potentiating existing activity or not affecting activity depending on the organism and serum used. Bactericidal activity, when removed by bentonite, was not restored by adding lysozyme. Absorbing sera with bacteria removed both bacteriolytic and bactericidal activity, the amount removed depending on the number of absorptions. Bacteriolytic, but not bactericidal, activity of sera absorbed with bacteria was restored by added lysozyme in the presence of EDTA. Serum absorbed with zymosar or antigen— antibody precipitates is inactive in bacterial killing.A requirement for added C′ in the bactericidal system can only be demonstrated in high dilutions of serum suggesting that C′ activity rather than antibody is the limiting factor.The experiments show that absorption techniques for removing lysozyme or antibody are non-specific and that lysozyme is involved in lysis but not in the killing of coliforms by bovine serum.     

牛前胃驰缓发病原因及防治对策

牛是特殊的反刍类动物,在生长发育阶段与其他动物养殖有较大的差别,一旦养殖管理不当,易造成胃部疾病的发生,其中前胃驰缓是很易发生的一类胃部疾病。该疾病虽然不是传染性疾病,不会造成严重的死亡,但是会影响牛的正常生长发育。该文主要论述牛前胃驰缓的发病原因和具体的防治对策。     

Early organogenesis of the caprine stomach

Early organogenesis of the caprine stomach was studied in a series of 11 embryos ranging from 6.5 mm neck-rump length (NRL) to 13.3 mm crown-rump length (CRL). In embryos with 6.5-6.7 mm NRL, a part of the primordial proper esophagus extended to the dorsal side of the primordial stomach. The primordial proper esophagus and its extension were lined with a simple epithelium and stained dark brown with Con A III, while the primordial stomach was weakly stained. In embryo with 7.3 mm NRL, the esophageal extension was separated from the proper esophagus by constriction, and became a primordial forestomach situated in an area outside the omental sac. In embryos with 8.3 mm NRL-10.7 mm CRL, primordial forestomach and primordial stomach were united and formed a spindle shaped primordial ruminant stomach with foregut rotation. The primordial ruminant stomach was similar to the primordial simple stomach except that it was more flattened laterally with the convex at the area of 'lesser curvature'. Primordial rumen, omasum and abomasum appeared from the spindle shaped primordial ruminant stomach in an embryo with 12.9 mm CRL. In an embryo with 13.3 mm CRL, primordial reticulum originated from an area between the primordial rumen and omasum.     

Modelos Matematicos Aplicados al Crecimiento Gástrico Ovino durante la Vida Intrauterina

Mathematical models describing the histomorphometric growth of ruminant stomach during prenatal life One hundred forty four ovine embryos and feti were used in an investigation to determine mathematical models describing the histomorphometric growth of tissues and compartments of the ruminant stomach. The results indicate that during prenatal life the diameter of the gastric chambers increase more slowly than the length. The tissue layers of the gastric walls, particularly the muscular tunic of all compartments demonstrated a uniform tendency toward more rapid development than the compartment walls proper.     

A comparative study on certain enzymes of the granulocyte from different ruminant species

In the present study the level of enzyme hydrolases (alkaline phosphatase, myeloperoxidase, elastase, arginase, lysozyme and β-galactosidase) of polymorphonuclear cell (PMN) granules in different ruminant species and their release in response to activation was studied. Buffalo PMN alkaline phosphatase activity was higher (P < 0.01) than in PMNs of cattle and goats. Interestingly, myeloperoxidase was higher in cattle PMNs and least in goat PMNs (P < 0.01), a similar pattern was observed in the distribution of enzyme arginase. As far as lysozyme is concerned, its activity was significantly higher (P < 0.01) in PMNs of buffaloes than in the case of cattle and goat PMNs. On activation, these cells released MPO and elastase, in all the species studied, while lysozyme was secreted only in buffalo PMN cells. Activity of certain enzymes related to oxidant defence systems such as glutathione peroxidase and glutathione reductase were higher in cattle and goats compared to that in buffaloes. These observations are likely to have bearing on immunodefense roles played by PMNs and reflected differences among the ruminant species studied.     

反刍动物瘤胃上皮的结构特点

反刍动物的胃是复胃,与单胃动物的胃不同。反刍动物主要以瘤胃中发酵产生的短链脂肪酸（SCFA）作为机体的能量物质,而绝大部分的SCFA又通过瘤胃上皮直接吸收,为宿主供能。因此,深入了解瘤胃上皮结构特点有助于对其吸收功能进行深入的研究。笔者主要对瘤胃上皮的解剖学特点、细胞学特点及超微结构进行了综述。     

山羊胃的腹腔镜探查

将腹腔镜从山羊胸骨柄后缘的腹中线插入腹腔,观察山羊在仰卧状态下瘤胃、网胃、瓣胃和皱胃,以及它们与肝脏、膈肌、腹壁和肠管的位置关系,并获得清晰的图片,为诊断和治疗反刍动物胃部疾病提供依据。     

糖蜜在反刍动物营养中的应用

糖蜜是甘蔗、甜菜等榨糖后的一种副产品.近年来,糖蜜已经成为了反刍动物饲养中一种必不可少的辅助性饲料.本文主要综述了糖蜜的营养特性及其在反刍动物营养中的作用,为其在反刍动物饲料中的研究、开发和应用提供理论依据.