单个氨基酸在人工配制饲料中的应用及其展望

<正> 单个氨基酸作为饲料添加剂正在日益受到世界各国的重视。饲料添加剂中第一、二限制氨基酸——蛋氨酸、赖氨酸,由于生产工艺成熟,世界年产量已经突破万吨关,尤其是蛋氨酸,1981年的产量已超过10万吨。它们在农、牧业发达的先进国家已经被广泛使用。最近被承认的第三限制氨基酸——色氨酸,过去一直因价格昂贵,只能作医药用。最近三年来,由于酶法新技术及新工艺的开发,使色氨酸的价格能大幅度的下降,这样一来作为饲料添加剂     

氨基酸在饲料中的应用

氨基酸在饲料中的应用（日）ＦＥＥＤＩＮＧ著朱海康,余毅译１日本的现状１．１饲料中添加氨基酸的种类现在,在日本作为饲料添加剂得到认可的氨基酸,在十种必须氨基酸中有：蛋氨酸、赖氨酸、色氨酸和苏氨酸四个品种,十种非必须的氨基酸中有：谷氨酸钠、甘氨酸和丙氨酸...     

添强L-赖氨酸、L-胱氨酸、L-酪氨酸对小猪增重的影响

<正> 高效又价廉地为人类提供更多高蛋白食品和工业原料,现代畜牧业都趋向以动物不同生长阶段,按需饲以全价混合饲料的饲养法。日粮采用氨基酸添加剂成为其中重要的技术措施之一。目前,许多科学技术先进的国家都制定了以氨基陵需要量为指标的营养标准。氨基酸添加剂的应用,有效地提高了畜牧饲养业的生产率和饲料利用率,节约了蛋白质饲料,降低了成本有力地促进了畜牧业的发展。     

植物性饲料添加剂

为了改善饲料的品质,提高饲料的利用率,防止畜禽疾病,人们已经广泛使用饲料添加剂。虽然它的用量很小,但作用很大,已为广大农村饲养业主所认识。 饲料添加剂的组成成分,大致可以分为四部分:一、维生素;二、氨基酸;三、矿质元素;四、其它成分,如抗生素、激素、酶制剂、抗氧化剂、驱虫剂、防毒剂等。     

日本用重组大肠杆菌酶法合成色氨酸

为扩大今后作为饲料添加剂的氨基酸的市场,三菱油化公司在农艺化学会上发表了酶法合成L-色氨酸产率的研究报告。     

真假饲料酵母的鉴别方法

真假饲料酵母的鉴别方法王艳华,张庆华,罗辉芬,马征远（辽宁省微生物研究所,朝阳１２２０００）随着饲料酵母工业均发展,饲料酵母作为一种饲料蛋白质添加剂,以其适应性强、菌体蛋白含量高、氨基酸种类齐全等优点而深受欢迎。近年来,由于原料供应紧张、价格上涨等因...     

欢迎复印氨基酸技术资料

1《胱氨酸厂废水利用研究资料》本刊编辑部收集了我国30年来关于“胱氨酸厂废水利用研究”中代表性的资料,集中介绍了废水的成份、去盐的方法和系统分离其他氨基酸、氨基酸饲料添加剂、氨基酸肥料生产工艺等。每套收复印费、邮寄费80元。[第一段]     

欢迎复印氨基酸技术资料

1《胱氨酸厂废水利用研究资料》本刊编辑部收集了我国30年来关于“胱氨酸厂废水利用研究”中代表性的资料,集中介绍了废水的成份、去盐的方法和系统分离其他氨基酸、氨基酸饲料添加剂、氨基酸肥料生产工艺等。每套收复印费、邮寄费80元。     

黄浦江的丝蚯蚓资源及其开发利用

丝蚯蚓是淡水底栖生物的组成部分,它具有较高的营养价值,于物中蛋白质含量高达70％以上,是鱼类及畜、禽的珍贵活饲料。又因其粗蛋白中氨基酸种类齐全,含量丰富,所以也是各种配合饲料的良好添加剂。     

合成苏氨酸的研究(Ⅰ)

<正> 苏氨酸(Threonine)是一种必需氨基酸,因此在氨基酸输液、综合氨基酸制剂、营养强化食品以及饲料添加剂等方面具有重要意义。此外,苏氨酸还有抗脂肪肝等药用效能,又是制造一类高效低过敏广谱抗生素—单酰胺菌素—的原料,很受发达国家的青睐。     

微生物饲料添加剂研究与应用进展

微生物饲料添加剂是依赖益生菌及其代谢产物发挥作用的绿色、安全的添加剂,在替代抗生素方面具有良好的发展前景。由于微生物饲料添加剂具有调节动物微生态平衡、增强免疫力、提高饲料转化率和生产性能、提高畜产品品质、改善养殖环境等诸多作用,因而在畜禽、水产等养殖中发挥着日益重要的作用。从概念剖析、作用机理、主要的微生物种类以及应用效果等方面,对微生物饲料添加剂的研究与应用现状加以简要综述,以期为进一步拓展微生物饲料添加剂的应用提供参考。     

微生物发酵中药饲料添加剂的研究进展

微生物发酵中药饲料添加剂突破性地将中药饲料添加剂和微生态饲料添加剂有机结合,具有提高免疫力、促进动物生长等作用,是替代抗生素的理想饲料添加剂。本文对近几年微生物发酵中药的机理及发酵后药性的变化、微生态饲料添加剂以及微生物发酵中药饲料添加剂进行了阐述。     

Ability of a commercial feed additive to modulate expression of innate immunity in sheep immunosuppressed with dexamethasone

In the first study, we tested the ability of a commercial feed additive (OmniGen-AF) to affect markers of innate immunity in immunosuppressed sheep and the ability of a pathogen challenge (mould) to affect the immune response to the additive. Treatments consisted of (1) control, (2) immunosuppressed with dexamethasone (DEX), (3) immunosuppressed plus the feed additive, (4) immunosuppressed plus Aspergillus fumigatus and (5) immunosuppressed, A. fumigatus and the additive. Animal health was monitored and indexes of innate immunity (neutrophil L-selectin and interleukin-1β (IL-1β)) were collected. DEX caused immunosuppression (i.e. reduced abundance of neutrophil L-selectin and IL-1β). This immunosuppressive effect was countered by the provision of the additive in the ration. Provision of mould in the ration increased the ability of the additive to regulate markers of innate immune function. A second study was completed to re-assess the properties of the additive and other feed products. The study consisted of seven treatments: (1) immunosuppressed, (2) immunosuppressed with additive, (3) immunosuppressed with additive in pelleted form (low-temperature pellet) and (4) immunosuppressed with additive in a high-temperature pellet. The remaining three treatments assessed abilities of three other additives to regulate markers of innate immune function. In this study, OmniGen-AF increased expression of neutrophil L-selectin abundance in immunosuppressed animals and this was unaffected by the pelleting temperature. None of the other additives affected markers of innate immunity. In these studies we discovered mechanisms by which a feed product may affect the immune function of ruminant livestock. The product countered DEX-dependent down-regulation of markers of innate immune function and its actions were enhanced by the presence of pathogen (mould) in the ration.     

Microbial Poly‐3‐Hydroxybutyrate (PHB) as a Feed Additive for Fishes and Piglets

The large‐scale use of petrochemical‐based plastics is damaging our environment. Discarded plastics are harmful to both marine and land animals, sometimes causing death when ingested. Biodegradable plastics have gained attentions from the public and the academia to reduce environmental burdens. Poly‐3‐hydroxybutyrate (PHB), the simplest and the best‐studied bioplastic member of the polyhydroxyalkanoate (PHA) family synthesized by many bacteria, has been studied as a feed additive for large yellow croaker fish and weaned piglets. The fish grow faster and gain more weight when 1% and 2% PHB is added as a feed additive, accompanied by increased survival rates. Weaned piglets are found to grow normally and showed no significant change in average daily weight gains, average daily feed intakes, feed efficiency, and organ developments when 0.5% PHB is added to the feed. It can therefore be concluded that biodegradable and biocompatible PHB is not harmful as a feed additive for marine large yellow croakers and sensitive weaned piglets. PHB therefore holds great promise as a plastic that combines biodegradability and biocompatibility with good tolerability as a feed supplement for animals.     

Performance optimization of polysulfone ultrafiltration membranes for riboflavin separation using design experiments

Polysulfone membranes containing different concentrations of polyethylene glycol (M.Wt: 600 Da) as additive was prepared using N,N-dimethyl formamide as solvent. The parameters chosen for the study of separation of vitamin B₂ were concentrations of additive and feed and solvent evaporation time. Box-Behnken design methods and analysis of variance have been applied to the experimental separation of vitamin B₂ by polysulfone membranes. Box-Behnken design with three levels of additive concentration (2.5, 6.25 and 10 wt%), feed concentration (0.002, 0.005 and 0.008%) and solvent evaporation time (10, 20 and 30 s) is used for the identification of significant effects and interaction for the batch studied. Second order polynomial regression model which was used for analysis of the experiment made significant effect. The experimental values are in good correlation with predicted values, and the correlation coefficient was found to be 0.9194.     

Effects of an immunomodulatory feed additive on the development of mastitis in a mouse infection model using four bovine-origin isolates

The goal of this study was to examine the ability of a commercially available feed additive (OmniGen-AF) to reduce mammary infections caused by a single strain of mastitic pathogens (Streptococcus uberis, Escherichia coli, Staphylococcus aureus and Klebsiella pneumoniae) and to examine the effects of the additive on markers of mammary immunity. Four experiments were completed using a murine model of bovine mastitis. Infection progression was examined using Sybr-green- and TaqMan-based quantitative PCR assays of 16S ribosomal DNA. Infection of the mammary gland with all pathogens caused rapid (24 to 48 h) appearance of pathogen DNA in mammary tissue. Provision of the feed additive for 2 weeks before infection significantly (P < 0.05) reduced the extent of pathogen DNA accumulation in models of S. uberis, E. coli and S. aureus infection. The additive was ineffective in reducing mammary infections caused by K. pneumoniae. We examined mechanisms of action of the additive through assessment of mammary concentrations of mammary myeloperoxidase (MPO), major histocompatibility complex 2 class II (MHC) and macrophage inflammatory protein-1α (MIP) messenger RNA (mRNA) concentrations and by examining serum complement C3 concentration. Infection of the mammary gland increased concentrations of MPO and MHC mRNAs (P < 0.05). Ability of the pathogen to elicit changes in mammary MPO and MHC gene expression was enhanced by the provision of the additive for 2 weeks before infection. These data imply that the additive increased the mammary inflammatory response and increased antigen presentation during a mammary infection. Value of the additive in preventing mastitis in cattle awaits additional studies using a bovine model and further evaluation of additional strains of the pathogens used in this study.     

Bioengineering for the industrial production of 2,3-butanediol by the yeast,Saccharomyces cerevisiae

World Journal of Microbiology and Biotechnology - Avilamycin, an excellent growth-promoting feed additive, produced by Streptomyces viridochromogenes, was widely used to promote the growth of...     

Effect of Endoxylanase and Iron Oxide Nanoparticles on Performance and Histopathological Features in Broilers

Biological Trace Element Research - Endoxylanase enzyme is used as poultry feed additive to degrade anti-nutritional factors like non-starch polysaccharides. Moreover, iron is one of the most...     

Probiotic Intake Increases the Expression of Vitellogenin Genes in Laying Hens

Probiotics and Antimicrobial Proteins - A promising approach for slowing down the rate of reproductive aging is the use of probiotic bacteria as a feed additive. In the current study was...     

Curcuma longa as feed additive in broiler birds and its patho-physiological effects

Broiler birds (Vencob chicken of 3 days old) when given feed mixed with powdered rhizome of Curcuma longa (CL; @ 1 g/kg) for 42 days of age, showed significant decrease in serum uric acid and albumin as compared to control, whereas significant increase was recorded in the level of serum total protein and globulin. Level of serum glucose, alkaline phosphatase, aspartate amino transferase and calcium showed no significant variation between the two groups. Micronutrient assay revealed significantly higher level of manganese, zinc, iron and copper in treated group as compared to control group. HA/HI test revealed better humoral response against RD vaccine in CL administered birds. Haematological study showed significantly higher haemoglobin and absolute neutrophil count in treated group. Addition of CL as feed additive also resulted in better growth rate, feed consumption and F:C efficiency in the treated birds. Thus, it could be concluded that powdered CL might be a useful feed additive, since it enhanced the F:C efficiency and had nephroprotective properties.