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霉菌毒素是霉菌在次生代谢过程中生成的一类毒性物质。谷物中霉菌毒素的污染会给养殖行业带来众多严重的经济损失。
多种霉菌毒素的存在会影响到食物在胃肠道内的消化水平，影响人和动物的健康状态，导致疾病甚至死亡。目前而言，世界已知的霉菌毒素种类超过400种。其中影响最为广泛的霉菌毒素可以主要六类：黄曲霉毒素，单端孢霉烯族毒素，烟曲霉毒素，玉米赤霉烯酮，赭曲霉毒素和麦角类毒素。从营养的角度看，霉菌毒素与饲料的脂肪、蛋白质、碳水化合物、维生素等具有较大的相关性。高脂饲料中对霉菌毒素具有抑制作用（mortality-sparing），但如果富含不饱和脂肪酸，则具有促扩散作用（growth-sparing）。一些霉菌毒素会引起脂质的吸收不良症，同时也能减少消化酶和胆汁盐的分泌，减少脂肪酸的合成，损害脂质运输通路。动物机体在缺乏维生素A、D或者核黄素时对霉菌毒素的敏感性增加，而在缺乏硫胺素（维生素B1）时敏感性降低。而霉菌毒素与维生素E、K的相关性目前尚未有明确的认识。霉菌毒素增加了动物机体对蛋白质的需求量，并且影响了动物机体内调节糖原分解合成酶的活性。
饲料原料——霉菌毒素最主要的来源
霉菌毒素防控最切实可行的方法是在饲料进入仓库前采用快速诊断系统检测饲料中霉菌毒素的含量。不同类型的快速诊断系统对于霉菌毒素的检测均已有相关的验证，这些诊断方式可以快速准确地检测出饲料中霉菌毒素的含量，从而避免给动物饲喂霉菌毒素超标的饲料。如果配方中每种原料的霉菌毒素含量均已知晓，那么配方师可以根据这些毒素的含量水平来准确设定添加脱霉剂的量。受到检测实验条件的限制，一般饲料企业会采用较为简单快捷的霉菌毒素检测方法如胶体金快速诊断试剂盒和ELISA检测试剂盒。这类检测试剂盒的优势在于能快速进行大批量的饲料霉菌毒素诊断，但其检测结果的准确度受到诸多因素的影响，包括检测试剂盒的质量、样品处理方式、检测流程、人为操作等。如果检测结果不精准，那么根据霉菌毒素数据进行的脱霉剂添加量调整也就没有什么意义。为了保证检测结果的准确性，饲料企业有必要定期对常规检测方法的检测结果进行进一步的验证。我们推荐饲料企业可以选择具有专业霉菌毒素检测服务的公司，对饲料检测人员进行系统化专业培训，定期对检测试剂盒的精准度进行验证，以避免饲料霉菌毒素超标事故的发生。
终端饲喂中多种霉菌毒素的共存
另外一种霉菌毒素防控的措施是检测终端饲料中霉菌毒素的含量。饲料企业一般仅检测几种重要原料的霉菌毒素含量，对于一些添加量较少或污染霉菌毒素概率较低的原料考虑到成本因素会忽略不检测。然而这类用量较少或污染概率较低的饲料也有可能会大幅度增加饲料中霉菌毒素的含量。这种检测终端饲料中霉菌毒素含量的方法可以帮助了解饲料产品的整体质量。
霉菌抑制剂——有效抑制霉菌但不能控制霉菌毒素
企业可以通过各种措施来控制仓库内饲料温度和水分含量，从而防止仓储霉菌毒素的生成（赭曲霉毒素和黄曲霉毒素）。在仓桶条件不能保证安全的情况下，使用霉菌抑制剂会是一个很好的选择。然而很多霉菌毒素在进入仓库前就已经产生（例如单端孢霉烯族毒素），而且任何一种霉菌抑制剂都不能对霉菌毒素进行降解。
有效的霉菌毒素管理
饲料霉菌毒素的最后一道防线是霉菌毒素脱毒剂。这类产品并不会在饲料仓储或饲料加工环节产生作用，而主要是在动物体内发挥功效。霉菌毒素脱毒剂在肠道内会通过吸附霉菌毒素的某些官能团来吸附霉菌毒素，或者通过生物酶解的方式将霉菌毒素降解。目前市场上较为常见的霉菌毒素脱毒剂往往会采用物理吸附、生物酶解和提高机体免疫抗氧化功能的方式来防控霉菌毒素。
Last but not least
饲料最终的消费者是动物，饲料企业所有关于霉菌毒素的工作都是为了给动物提供健康安全的饲料。因而对于霉菌毒素最有发言权的应该是我们所养殖的动物。动物不会说话，但它们可以通过一些行为、症状或者病变来默默地向养殖者表达观点。但我们往往会忽略掉这些细微的信息。
随着科学的发展，科学家们已经研制出了研究出一整套针对霉菌毒素敏感有效的诊断技术，包括分析肝、肾中霉菌毒素及其代谢产物的含量（科学家称之为生物标记物 biomarker）。这些生物标记物不仅可从分子水平探讨霉菌毒素对机体组织损伤的作用机制，而且在准确、敏感地评价早期、低水平的损害方面有着独特的优势，可提供早期预警，很大程度上为临床兽医师提供了辅助诊断的依据。这套诊断技术经大量实验数据证明有效，目前已经被欧洲许多国家用于监控器官中霉菌毒素限量。
The English version
Mycotoxin mold is generated in the process of secondary metabolism of toxic substances. Grain of mycotoxin contamination can bring many serious economic losses to aquaculture industry.
The existence of a variety of mycotoxin will affect the food in the digestive level in the gastrointestinal tract, affect human and animal health, causing disease and even death. For now, the world of mycotoxin known species more than 400 kinds. Which can influence most widely mycotoxin mainly six types: yellow aspergillus toxin, single-ended spore alkene toxins, smoke aspergillus toxin, corn gibberellic ketene, ochre and aspergillus toxin and ergot toxoid. From the nutritional point of view, mycotoxin and feed the fat, protein, carbohydrate, vitamin and so on has great relevance. High-fat diet has inhibitory effect on mycotoxin (mortality - sparing), but if is rich in unsaturated fatty acid, has its effect on promoting proliferation (growth - sparing). Some mycotoxins cause lipid malabsorption syndrome, but also can reduce the secretion of digestive enzymes and bile salt, reduce the number of fatty acid synthesis, damage of lipid transport pathways. Animal body in A lack of vitamin A, D, or when the riboflavin of mycotoxin sensitivity increases, and in the absence of thiamine (vitamin B1) reduced susceptibility. Mycotoxin and the correlation of vitamin E, and K has yet to have a clear understanding. Mycotoxin increased demand for animal organism on the protein, and affected the animal inside the body to adjust decomposition of glycogen synthase activity.
The most important source of feed ingredients, mycotoxins
Is the most practical methods in the prevention and control of mycotoxin feed before entering the warehouse using rapid diagnostic system testing of mycotoxins in feed content. Different types of rapid diagnostic system for detection of mycotoxin were related to verification, the diagnostic method can rapidly and accurately detect the content of mycotoxins in feed, to avoid to feeding mycotoxin excessive amounts of feed the animals. If mycotoxins of each raw material in the formula have been known, then the formula can accurately according to levels of these toxins are set up to add the amount of mildew agent. By detecting the limitation of experimental conditions, the general feed enterprises will use a relatively simple and quick mycotoxin detection methods such as colloidal gold rapid diagnostic kit and ELISA test kit. Such detection kit has the advantage of large quantities of feed mycotoxins diagnosis quickly, but the accuracy of the test results affected by many factors, including the quality of detection kits, sample processing method, test process, the artificial operation and so on. If test result is not accurate, then according to the data of mycotoxin mildew remover content adjustment also have no meaning. In order to ensure the accuracy of the test results, feed enterprise is necessary to regularly test results of conventional detection methods for further verification. We recommend feed enterprises can choose to have professional mycotoxin testing services company, systematic professional training, feed testing personnel on a regular basis to certify the accuracy of detection kits, to avoid excessive feed mycotoxins accidents.
Terminal feeding in a variety of coexistence of mycotoxin
Another is the measures of prevention and control of mycotoxin detection terminal of mycotoxins in feed content. Feed enterprises are generally only to detect the contents of several kinds of important raw material of mycotoxin, for some add less or pollution mycotoxin probability of lower raw materials considering the cost factor will be ignored. However such amount or less pollution probability lower feed are also likely to be substantially increase the amount of mycotoxins in feed. This method of detection terminal content of the mycotoxins in feed can help understand the overall quality of the feed products.
Mould inhibitor -- but not effective inhibitory control mycotoxin
Enterprise can through a variety of measures to control the warehouse of feed temperature and moisture content, so as to prevent the warehouse of mycotoxin generated (ochre and aspergillus toxin and aflatoxin). Under the condition of the warehouse barrels cannot guarantee safety, use mould inhibitor can be a good choice. But a lot of mycotoxin were produced before entering the warehouse (single-ended spore of alkene toxins, for example), and any kind of mould inhibitor can degradation of mycotoxin.
Effective management of mycotoxin
Feed mycotoxins of the last line of defense is a mycotoxin poison. This kind of product will not be in storage or feed feed processing link, and mainly function in animal body. Mycotoxin poison off in the gut will pass some functional groups of mycotoxin to adsorption mycotoxin, or through the mycotoxin degradation enzyme solution way. More common on the market at present the mycotoxin poison off often using physical adsorption, biological enzymolysis and improve the body's immune to prevention and control mycotoxin antioxidant function.
Last but not least
The final consumer is animal feed, feed enterprises all works about mycotoxins are to provide health and safety of feed for animals. Thus the mycotoxin most voice should be that we farmed animals. Animals can't talk, but they can pass some behavior to the farmers, the symptoms or lesion to silently. But we tend to ignore these subtle messages.
With the development of science, scientists have developed a developed a set of mycotoxin sensitive and effective diagnosis technology, including the analysis of mycotoxins in liver, kidney and its metabolite levels (scientists call them biomarkers biomarker). These biomarkers can be not only from the molecular level to study the effect of mycotoxin on tissue damage mechanism, and early in the accurate, sensitive evaluation, the low level of damage has a unique advantage, can provide early warning, to a large extent for clinical veterinary provides auxiliary diagnosis basis. The diagnosis technology of a lot of experimental data show that effective, at present has been in many European countries used to monitor organs in mycotoxin.
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