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我们在选择霉菌毒素脱毒剂类产品（下称脱毒剂）时往往面临一个问题的困扰，即是如何正确评估此类产品，然而目前国内尚无对应的国家标准或者行业标准，各品牌产品所执行的均是自己的企业标准，于是各种方法理论目不暇接。本节对不同评估方法的可行性、准确性略作梳理。
脱毒剂的了解与评估，按手段可分为资料了解、实验室评估和动物试验评估，其中实验室评估又有体外方法、模拟体内（仿生）方法等；按评估目的可分为有效性评估、安全性评估、稳定性评估等等，以下就实验室评估和动物试验评估加以分析。
1、实验室评估
正确有效的实验室评估方法可以帮助我们快速分析、认知某个添加剂产品，继而协助或指导动物试验的后续进行，实验室评估快捷，没有动物试验那样成本高，工作量大的缺点。实验室评估方法，无论是体外吸附分析或者是仿消化道环境的吸附分析，均是旨在创造一种毒素与脱毒剂相反应的环境，反应后再通过不同检测器进行量化分析，以此来判断和证明一种脱毒剂对某种毒素具备多少处理能力。理论上，如果一种物质在体外不能良好处理某种毒素，那么很可能在体内也是如此，如果想评价不同品牌产品的效果，实验室吸附评估方法作为首当其冲的方法还是很有意义的。如Diaz在缓冲液体系下比较多种脱毒剂剂结合AFB1的效果（2002）；如Sabater- Vilar模拟消化道环境比较常见脱毒剂对DON和ZEN 的处理能力（2007），实验室方法能直观评价吸附剂对霉菌毒素的吸附性能，作为一个评价手段，应该能起到筛选区分脱毒剂的效果。然而，实验室评估方法不是一成不变的吸附分析方法，进行实验室评估时需要考虑更多因素。举两个例子：一、现有的脱毒剂处理毒素的理论机理有很多，有物理吸附的，有化学结合的，有生物降解的；有效成分也不一，有非金属粘土矿物的、有微生物的、有酶制剂的、有植物多糖或真菌多糖成分的，不一而足。因此，不可能用实验室吸附试验去评估一个宣传以微生物或酶解毒素为机理的脱毒剂，也不可能用粗灰分多少去评判一个无机或有机脱毒剂的优劣。二、霉菌毒素的在谷物里的存在形式不是一成不变的，有各种结合态，在动物体内也因不同代谢阶段而呈不同衍生物和异构体，这使得实验室评估方法的针对性和准确性都会有偏差甚至偏离。比如霉菌毒素可以是纯单体游离，可以是与基质组成复合物，物理可溶或被束缚(如伏马毒素与淀粉分子，赭曲霉毒素呕吐毒素与寡聚糖分子结合)，可以是与植物或真菌结合的DON-3-葡萄糖苷和赤霉烯酮-14-硫酸盐。
2、动物实验评估
按照官方对饲料添加剂的评估方法要求，动物实验评估是必不可少的一个环节。以评估脱毒剂有效性试验为例，饲养实验分组至少5个组别，分别是正负对照组和3个梯度的处理组。如（1）正对照组，不含霉菌毒素和吸附剂；（2）负对照组：含有霉菌毒素的日粮；（3）至（5）：含有不同浓度脱毒剂的霉变日粮。同时要求每个组别设定6个重复以上。可见脱毒剂动物试验评估是一项成本大、工作量大的工作。
脱毒剂的动物试验评估，可分为短期有效性评估和长期有效性评估。短期有效性评估可通过观察和测量某指标、某外观状况以判断该脱毒剂是否具有处理毒素的效果，如短期控制牛乳中黄曲霉毒素M1残留、短期控制青年母猪的假发情问题。而长期有效性试验，除了考量增重、采食量、死亡率、饲料效率等必备指标外，还可以通过测定动物的其他生理生化指标来说明脱毒剂对霉菌毒素的处理程度，如测定不同处理组的血液常规指标，包括血清总蛋白、白蛋白、球蛋白、胆固醇等；或其他生化免疫指标如谷草转氨酶、谷丙转氨酶和谷胱甘肽硫转移酶等；或者测定母畜的E2、LH等内分泌指标；进一步深入研究的话，可以评估血液或某组织中毒素的含量以及排泄物中毒素含量，以评估使用脱毒剂后毒素的去向。在脱毒剂对霉菌毒素的有良好处理效果的前提下，那么这些生理生化指标也不会因一定量毒素的出现而带来波动。
3、其他评估内容
对于脱毒剂的其他评估内容，主要就是安全性和其他破坏性问题，如绝大多数的非金属粘土矿物的非选择性吸附特性，是否对饲料中的微量营养物质产生干扰，或者是否给饲料带来重金属污染等降低饲料品质和安全性的危害。这就要求在评估脱毒剂有效性的同时要考量其对一些维生素、药物、微量元素的吸附干扰作用、以及其砷、铅、氟、二噁英含量是否达到危害饲料安全的程度。.
The English version
We take off our agents in choosing a mycotoxin products (hereinafter referred to as stripping agents) often face a problem, that is, how to correctly evaluate this kind of product, however, the current domestic, there is no corresponding national standards or industry standards, each brand products which are performed by their own enterprise standards, and the ways of theory. This section of the different assessment method is feasible, accurate guarded.
To take off the poison of understanding and evaluation, according to the method can be divided into information, laboratory evaluation and assessment of animal testing, including laboratory evaluation and the in vitro method, simulated the body (bionic), etc.; According to the evaluation purpose can be divided into the effectiveness evaluation, safety assessment, stability evaluation and so on, the following laboratory evaluation and assessment of animal testing analysis.
1, laboratory evaluation
Correct effective laboratory evaluation method can help us to quick analysis, cognitive an additive products, and then to assist and guide the follow-up of animal testing, laboratory evaluation and fast, no animal test that the high cost, workload big shortcoming. Laboratory evaluation method, either in vitro adsorption or adsorption is the imitation of the digestive tract environment analysis, are designed to create a kind of poison with poison off the opposite should be environment, reaction after a quantitative analysis by different detector, to judge and prove a poison off for some toxins have how much processing power. Good in theory, if a substance in vitro can't deal with some kind of poison, so it is likely in the body, if you want to evaluate the effect of different brand products, laboratory evaluation methods as a way to bear the brunt of adsorption is very meaningful. Such as Diaz in the buffer system comparing a variety of agents remover in combination with the effects of AFB1 (2002); Such as Sabater - Vilar simulated gastrointestinal environment is common to take off the poison of the processing capacity of DON and ZEN (2007), the laboratory method can directly evaluate adsorbent for the adsorption performance of mycotoxin, as a means of evaluation, should be able to play a screening to distinguish the effect of the poison. However, laboratory evaluation method is not static adsorption method, need to consider more factors in laboratory assessment. Two examples: first, the existing agents to deal with the theoretical mechanism of toxin has a lot of, have physical adsorption, chemical combination, biodegradable; Effective components also differ, non-metallic clay mineral, microbes, enzymes, plant polysaccharides or fungi polysaccharide composition, and so on. Adsorption, therefore, can not use laboratory test to evaluate a publicity for microorganism or enzyme toxins mechanism of poison, also can not use coarse ash how to judge the pros and cons of an inorganic or organic agents. Second, the existence of mycotoxins in grain form is not static, with all kinds of combination state, in animals also are different due to different metabolic phase derivatives and isomer, this makes the pertinence and accuracy of the laboratory evaluation method will have a deviation even deviation. Mold toxins can be pure monomer free, for example, can be a complex with the substrate composition, physical or soluble bound (such as v toxins and starch molecules, ochre and aspergillus toxin vomiting toxins and widowhood chitosan molecules), can be combined with plant or fungi DON - 3 - glucoside and gibberellic ketene - 14 - sulfate.
2, animal experiment evaluation
In accordance with the requirements for the official evaluation methods for feed additives, animal experiment evaluation is one of the essential link. To assess the efficacy of poison off test, for example, raising the experimental group at least five categories, respectively is the processing of positive and negative control group and three gradient group. Such as (1) is the control group, excluding mycotoxin and adsorbent; (2) the negative control group: the diet containing mycotoxins. (3) to (5) : mildew diet containing different concentrations to take off the poison. At the same time requires each group set 6 repeat. Visible to take off the agent evaluation of animal testing is a big cost and volume of work.
Take off poison animal tests and evaluation, can be divided into short-term effectiveness assessment and long-term effectiveness assessment. Short-term effectiveness evaluation by observation and measurement of a certain index, the exterior conditions to determine whether this to take off the poison has to deal with the effect of the toxin, such as short-term control of aflatoxin M1 residue in milk, short-term control of the gilt off heat problem. Effectiveness and long-term test, weight gain, feed intake, in addition to the considerations, proper index, mortality rate, feed efficiency, can also by measuring the other animal physiological and biochemical indexes to show off agent handling of mycotoxin, blood routine indexes such as the determination of different treatment group, including serum total protein, albumin, globulin, cholesterol, etc.; Or other biological immune indexes such as aspertate aminotransferase, alanine aminotransferase and glutathione s transferase, etc.; Or determine the E2, LH female endocrine indexes such as; Further in-depth study, you can evaluate the content of toxins from the blood or tissue and toxin content in the waste, and to assess the use of poison off the toxin. In to take off the poison of mycotoxins has good treatment effect under the premise of these physiological and biochemical indicators will not bring fluctuations due to the presence of the amount of toxin.
3, other evaluation content3
For take off poison other assessment content, security and other destructive is main problem, such as the vast majority of non-metallic non selective adsorption characteristics of clay minerals, whether to feed the micronutrients to produce interference, or bring to feed the harm of heavy metal pollution reducing feed quality and safety. This request in the evaluation of effectiveness to take off the poison for some vitamins, medicines, and at the same time to consider the adsorption and interference effect of trace elements, and its arsenic, lead, fluoride, dioxin levels if the degree which endanger the safety of the feed. .
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