饲料中霉菌毒素生物降解的研究进展

霉菌毒素的高毒性和强致癌性严重威胁动物生产性能和人类健康,每年给畜牧业和食品工业带来巨大经济损失。因物理和化学去毒方法存在诸多应用缺陷,故作为一种安全、高效、环保的方法,霉菌毒素生物降解法备受关注。本文对霉菌毒素毒性的作用机制、生物降解的研究进展进行综述,对目前生物降解研究存在的困难提出策略和建议,为饲料和食品中霉菌毒素的生物解毒提供理论基础和实践依据。     

黄曲霉毒素生物降解的研究进展

黄曲霉毒素B1具有强毒性、强致畸性和强致突变性,是危害最大的真菌毒素之一.黄曲霉毒素污染食品、饲料等严重危害消费者和动物的健康,给相关行业和畜牧业生产带来巨大的经济损失.由于物理和化学方法去除食物中的黄曲霉毒素存在种种应用缺陷,目前生物降解黄曲霉毒素成为安全、高效且环保的方法而备受关注.本文就国内外黄曲霉毒素生物降解的研究作一综述,同时对生物降解应用前景予以展望.     

有机磷降解酶及毒素解毒酶的分子改良与产品研制

课题内容、目标： 针对当前已分离得到的有机磷降解酶、黄曲霉毒素解毒酶和N-酰化高丝氨酸内酯降解酶的缺陷与不足，以蛋白质组学和生物信息学为基础，利用基因重组、定点突变、随机突变、蛋白质分子修饰等手段及蛋白质分子设计技术，结合生物信息学理论，对有机磷降解酶、黄曲霉毒素解毒酶关键氨基酸残基的分析，并通过理性设计和密码子偏好性改造等，着重对酶蛋白特性进行分子改良，     

浅析霉菌毒素对猪的危害及防治

正霉菌毒素主要是指霉菌在其所污染的食品中产生的有毒代谢产物,它们可通过饲料或食品进入人和动物体内,引起人和动物的急性或慢性毒性,损害机体的肝脏、肾脏、神经组织、造血组织及皮肤组织等。目前,饲料中检测到的霉菌毒素已超过350种,生猪养殖过程中对其造成严重影响的主要有黄曲霉毒素、赭曲霉毒素、呕吐霉素、玉米赤霉烯酮(F-2毒素)等。下面就几种霉菌毒素的危害和防治作一浅析。一、几种主要霉菌毒素及危害(一)黄曲霉毒素黄曲霉毒素是一类化学结构类似的化合物,均为二氢呋喃香豆素的衍生物,主要由黄曲霉和寄生曲     

饲料中几种霉菌毒素对动物免疫机能的影响

我国一些地区饲料霉变问题相当严重,饲料霉变问题是饲料工业和畜牧业生产中不可忽视的问题。霉菌毒素对动物的影响除中毒和致死外,更重要的是不易被发现机体免疫机能下降、生长受阻、生产性能和抗病力降低。故饲料中霉菌毒素有“隐形杀手”之称。饲料霉菌毒素污染问题已引起世界的广泛关注。１饲料中的霉菌毒素种类目前在饲料中发现的霉菌毒素有:黄曲霉毒素(Ａｆｌａｔｏｘｉｎ,ＡＦ)、黄曲霉毒素Ｂ１(ＡＦＢ１)、葡萄穗霉毒素(Ｓｔａｃｈｙｂｏｔｒｙｏｔｏｘｉｎ,ＳＡＴ）、单端孢霉毒素、赭曲霉毒素等。这些霉菌毒素都能损伤机体特定的…     

饲料中黄曲霉毒素的危害及去毒方法

黄曲霉毒素是毒性极强的真菌毒素,严重威胁人和动物的健康。本文主要综述了牛奶中黄曲霉毒素的来源、危害以及如何运用物理法、化学法、生物法去除饲料中的黄曲霉毒素。     

有机磷降解酶及毒素解毒酶的分子改良与产品研制

针对当前已分离得到的有机磷降解酶、黄曲霉素解毒酶和N-酰化高丝氨酸内酯降解酶的缺陷与不足，以蛋白质组学和生物信息学为基础，利用基因改组、定点突变、随机突变、蛋白分子修饰等手段及蛋白质分子设计技术，结合生物信息学理论，对有机磷降解酶、黄曲霉毒素解毒酶关键氨基酸残基的分析，并通过理性设计和密码子偏好性改造等，着重对酶蛋白特性进行分子改良，     

黄曲霉毒素的生物降解研究进展

黄曲霉毒素(Aflatoxins)是黄曲霉(Aspergillus flavus)、寄生曲霉(Aspergills parasiticus)等真菌的次级代谢产物,具有高毒性和致癌性,是饲料中主要的污染物之一。近年来黄曲霉毒素的降解成为研究热点,对黄曲霉毒素的特性、脱毒方式尤其是生物降解及其机理和降解产物的研究进展进行了综述。     

抗霉菌毒素饲料添加剂的研究与应用

饲料在生产过程中易受空气中广泛存在的霉菌污染,被污染的饲料经过一段时间的贮存后将产生霉菌毒素,这些毒素对动物的生长将造成一定的危害,人类食用了这类动物食品后进而威胁健康。目前,动物饲料霉菌毒素污染问题日益引起人们的关注。文章介绍了陈化饲料中常出现的霉菌毒素,并对控制这些霉菌毒素危害的饲料添加剂进行了论述。     

要充分认识饲料霉菌毒素的危害性

据统计，世界上谷物总量的２５％为霉菌毒素所感染，全世界每年由于霉菌污染粮食和饲料所造成的经济损失可达数千亿美元。我国是霉菌毒素的重灾国，一些地区尤其是南方地区饲料霉变问题相当严重，虽然某些饲料加工工艺（例如高温调质）可以杀死部分霉菌等微生物，但霉菌代谢所产生的毒素却难以消除，霉菌毒素污染饲料后，不仅直接危害动物的健康和人类健康，而更多的情况是导致饲料营养价值下降，降低动物免疫力和生产性能，造成饲料企业和养殖户大很大的经济损失，所以无论是饲料企业，还是养殖户都应对霉菌素的危害提高认识。１霉菌及霉菌…     

食品中黄曲霉毒素及理化脱毒措施研究进展

黄曲霉毒素是一类致癌性极强的真菌毒素,被世界卫生组织列为一级致癌物,常存在于发霉的粮油制品中。概述了黄曲霉毒素的生物学特性、化学结构特点、理化性质,并着重阐述了黄曲霉毒素B1的致癌作用机制,综述了近年来黄曲霉毒素的理化脱毒措施,以期对食品中黄曲霉毒素脱毒技术体系研究提供参考。     

安徽省饲料玉米贸易及其与畜牧业发展之间的关系

对安徽省饲料玉米的商贸情况及其与畜牧业发展之间的关系进行了调查。结果表明,安徽省2008年饲料行业的玉米需求量为114.157万t,全省养殖业的玉米需求量达683.737万t,其中通过贸易输入的玉米达397.14万t,通过养殖企业、饲料企业和个体输入的玉米占48.6%。玉米总量与安徽省肉类、奶类产量及牧业总值显著相关,而与禽蛋产量的相关性不显著;该省的玉米产量与肉蛋奶产量及牧业总值无明显的相关性,但通过贸易输入的玉米量与肉类、奶类产量及牧业总值显著相关。     

Utilization of Chinese Herbal Feed Additives in Animal Production

The experimental knowledge on efficacy,possible modes of action and aspects of application of Chinese herbs as feed additives for animal production are reviewed in this article.Chinese herbs commonly contain protein,carbohydrate,fat,vitamins,and mineral which are necessary nutrients to the growth of animal.Polysaccharide,organic acid,alkaloids,and essential oils involved in Chinese herbs can improve the immune function of livestock.Currently,numerous studies have demonstrated anti-oxidative and anti-microbial efficacy and the assumption that Chinese herbs may improve the flavor of meat,which has been confirmed by some observations,but the mode of this action is still unclear.Moreover,several observations support the hypothesis that herbal feed additives may favorably affect gut functions (e.g.,enzyme activity,microbial eubiosis) in vitro.Such effects may explain a considerable number of practical studies with livestock reporting improved production performance after providing herbal feed additives.In summary,available evidence indicates that herbal feed additives may have the potential to add to the set of non-antibiotic growth promoters for use in livestock,such as organic acids and probiotics.However,a systematic approach toward the efficacy,mode of action and safety of herbal compounds used as feed additives for animal production seems to be required in the future.     

基于饲料需求的我国饲料谷物需求预测分析

为探讨肉蛋奶生产对饲料谷物需求量,利用误差修正模型和ARIMA模型,基于1980—2013年我国肉蛋奶产量和饲料谷物消费量的数据进行预测分析。结果发现,未来肉蛋奶产量和饲料谷物需求量均呈现逐年增长的态势,2025年肉蛋奶产量将达到18 788万t,饲料谷物需求量将突破20 000万t,达到21 596万t。未来饲料谷物的供需平衡关乎我国畜产品的有效供给。因此,合理扩大饲料谷物的生产面积,提高单产水平以及适度进口、加大饲料科技投入和提高科技转化效率可能是缓解饲料谷物需求压力的有效途径。     

Role of live microbial feed supplements with reference to anaerobic fungi in ruminant productivity: A review

To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials(DFM) for improved animal performance in terms of growth or productivity. This becomes all the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production efficiency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes(i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder) are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing naturally occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi(ARF) based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cell-wall degrading cellulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Significant improvements in the fiber digestibility were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro supplementation of ARF as DFM. Therefore, DFM especially ARF will gain popularity but it is necessary that all the strains are thoroughly studied for their beneficial properties to have a confirmed ‘generally regarded as safe' status for ruminants.     

饲料中霉菌毒素的危害及其控制

介绍了饲料中常见霉菌毒素的种类、毒性、危害及其敏感动物,并从预防与去毒2个方面,阐述了控制霉菌毒素危害的措施及其检测方法.     

酶联免疫法检测盐酸克伦特罗的试验报告

盐酸克伦特罗酶联免疫反应测试盒适用于尿样、组织和饲料等样品中克伦特罗残留的定量检测。克伦特罗作为一种主要的β-兴奋剂应用于畜禽肉制品生产中,用以提高肌肉和脂肪的比例并加快生长速度。由于克伦特罗可作为肌肉舒缓剂用于人类疾病治疗,在畜禽中过量残留可能会对消费者造成危害,为此,被禁止在食品生产中应用。根据美国FDA和WHO规定,在肌肉和脂肪中克伦特罗的含量不能超过0.2ng/g,在肝脏和肾脏中其含量不能超过0.6ng/g。与传统的HPLC或GC-MS方法相比,酶联免疫方法具有操作简便、灵敏度高、成本低的优点。盐酸克伦特罗酶朕免疫反应测试盒为养殖者和政府监督管理部门提供了更准确快速检测克伦特罗残留的方法,该试剂盒的特点包括4方面,第一,该试剂盒的提取方法能达到75%～95%以上的回收率,可以不需用有机溶剂并在10～30min之内完成提取过程。第二,高灵敏度(0.05ng/g);低检测下限(肉类/脂肪0.025ng/g,尿液0.05ng/ml,饲料0.2μg/kg)。第三,检测过程只需不到2h。第四,高重复性。     

Bacillus subtilis Co-transfected with a Lysine-rich and a Methionine-rich Protein Gene and Its Effect on Cow Milk Production

The probiotic Bacillus subtilis(B. subtilis) was widely applied in animal production as feed additive. Lysine(Lys) and methionine(Met) were the two most important limiting amino acids in livestock animal feed. Raising Lys and Met contents in B. subtilis would provide better effects for animal production and save Lys and Met supplements. We still didn't know whether Lysrich and Met-rich protein genes from plants could be transfected into B. subtilis and expressed at a high level so as to improve animal production, such as milk production as an additional diet. The Lys-rich protein gene(Cflr) and Met-rich 10 ku-δ Zein were cloned from pepper anther and maize endosperm, respectively. Then they were constructed into plasmids individually and successfully cotransfected into B. subtilis. Upon IPTG induction, m RNAs and protein expressions could be observed. Lys and Met contents in the fermentation broth were raised by 65.92% and 46.39%, respectively. After feeding 200 g and 400 g · cow~(-1) · d~(-1), transgenic B. subtilis fermentation broth, the milk yield, milk protein and milk fat contents all significantly increased. The Lys-rich protein gene(Cflr) and Met-rich 10 ku-δ Zein were successfully transfected into B. subtilis. Contents of Lys and Met in the transgenic B. subtilis obviously raised and the fermentation broth of the transgenic bacteria could effectively improve milk yield and quality.     

2013年四川省饲料原料中霉菌毒素污染情况调查

为了解2013年四川省饲料原料受霉菌毒素的污染情况,采集四川省饲料原料120个,采用酶联试剂盒和液质联用仪两种方法,测定其中黄曲霉毒素B1、玉米赤霉烯酮、呕吐毒素、赭曲霉毒素A和T-2毒素的含量。结果表明,四川省饲料原料中霉菌毒素超标率均低于全国平均水平,玉米赤霉烯酮和呕吐毒素污染程度相对较重,黄曲霉毒素B1、赭曲霉毒素A和T-2毒素超标率为0。