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業(yè)內都知道霉菌毒素的問題是中國飼料原料乃至全球飼料原料，或者是我們在養(yǎng)殖過程中碰到的最大的問題。關于霉菌毒素的消除，霉菌毒素吸附劑是一個比較好的方法，吸附劑價格從幾元錢到幾十元錢，甚至上百元錢每千克，價格差這么大，到養(yǎng)殖中到底能起多大的效果?今天在這里，我簡單分享一下霉菌毒素吸附劑的評估方法，以及添加劑、防霉劑等等問題。
霉菌毒素吸附劑的評估
在中國農(nóng)業(yè)部的三個目錄中是沒有霉菌毒素吸附劑這個條款的，美國也沒有，歐洲也沒有，在飼料工業(yè)術語中也沒有這個詞，這個詞僅用于商業(yè)和學術上的討論。霉菌毒素吸附劑在官方上也沒有得到認可，最大的問題就是很多飼料企業(yè)到農(nóng)業(yè)部去反應，說自己按照霉菌毒素吸附劑廠家的檢測和建議，添加了霉菌毒素吸附劑之后，飼料被官方抽查，檢測結果不合格，把吸附劑的廠家告到農(nóng)業(yè)部去了。農(nóng)業(yè)部專門對這方面做了解釋，是因為吸附劑在農(nóng)業(yè)部沒有被認可，這是第一個問題。
第二點，關于吸附劑的作用，很受關注，褒貶不一。它的評估方法有體內和體外兩類，體內評估的方法很難說得清楚，體外的方法，所有賣霉菌毒素吸附劑的廠家到飼料公司做宣傳時都能給出很好的數(shù)據(jù)，但一個科學的方法一定要證明飼料原料霉菌毒素是如何轉移的，這一點要說清楚，能證實，這個評估的方法才是有效的方法。
現(xiàn)在被吸附劑廠家所普遍采用的方法是這樣的：基本上把霉菌毒素的標樣游離，加入到緩沖溶液中，加上毒素吸附劑，經(jīng)過振動、離心、分離，取上清。我認為這樣的數(shù)據(jù)最大的好處是操作簡單，但是這脫離了實際的情況，因為霉菌毒素在我們的飼料中、或者飼料原料中并不是以游離狀態(tài)存在的，或者說游離存在的只是一部分，還由一部分是結合態(tài)的，如果這樣的評估是加了一個游離毒素的標樣，這樣的數(shù)據(jù)和實際是相差甚遠的。
有一些廠家也看到了前一個方法的問題，第二個方法進行了一定改進，叫做空白基質的方法。取一個空白基質，比如說玉米或者淀粉，這里面是不含任何毒素的，加上標準樣品，實際上就加了一定的干擾，再把這些東西加到緩沖濃液里面去，經(jīng)過振蕩、離心，同樣認為上清液中毒素的減少是吸附的數(shù)量。這個時候我們認為它跟現(xiàn)實的原料情況還是不一樣，雖然增加了干擾因子，但這個數(shù)據(jù)還不是很可靠。
新方法試驗
基現(xiàn)在廠家給我們提供的方法是這樣，我們自己通過這幾年的摸索形成了另一個方法，我們認為毒素的吸附或者毒素跟原料是有結合力的，吸附劑必須把毒素跟原料的蛋白或者淀粉的結合力破壞掉，形成一種結合物，這個結合物在腸液或者胃液中不被解析，通過這個途徑，我們就做了一個已知毒素含量的天然底物，然后加上吸附劑，通過仿生消化的方法，讓毒素和吸附劑形成一個結合物，再經(jīng)過分離。這個方法的創(chuàng)新點，就是把霉菌毒素吸附劑加進去以后，可以把毒素能夠分離出來，把吸附劑分離進來，能明確指出霉菌毒素從原料中轉移到什么地方去了。我們幾乎用了一年半的時間想分離的方法，最后攻克了分離這個難點。但是現(xiàn)在看來，吸附劑的回收率只能做到75%左右，還不是很理想，有待進一步的提高。我認為這樣一個毒素轉移的過程，能把它講清。
用這樣的方法，我們看它對霉菌毒素的吸附。選擇一個被黃曲霉素污染的棉粕，測定空白時的數(shù)據(jù)，然后加蒙脫石，進行體外消化，把棉粕和蒙脫石分離出來，分離出來的蒙脫石就能達到80ppb左右。經(jīng)過分離以后，黃曲霉毒素都轉移到分離出的吸附劑里了。再看牛的飼料，前面是按每噸5千克添加的，現(xiàn)在有這樣一個添加方式，就是按照0.1千克、0.3千克，1千克，3千克，5千克，7.5千克，10千克，每噸飼料按這樣的比例添加，沒有添加前牛的飼料是54ppb，在不同添加比例的時候，牛的飼料經(jīng)過分離，毒素含量明顯下降，加到5千克到7.5千克的時候，吸附力上升的數(shù)據(jù)就比較低了，一般都是在5千克上下，這是一個比較好的吸附。
不同廠家的吸附劑，對黃曲霉毒素，對嘔吐毒素，對赤霉烯酮，最后的結果不同，包括蒙脫石在內的對黃曲霉毒素的吸附還算是比較有效，好的話能做到70左右，對嘔吐毒素跟赤霉烯酮的吸附，按我們這個方法做出來的效果是非常有限的，就是嘔吐毒素好的廠家能做到25左右，赤霉烯酮做到20左右。
霉菌毒素吸附劑的選擇
通過這些數(shù)據(jù)我們能看到一些什么?第一是關于毒素吸附劑的問題，雖然官方?jīng)]認可，但是商品化的只有它能做，其他的不行。但是評價方法確實沒有公認的標準，直接加標樣，緩沖液的吸附效果是比較好，數(shù)據(jù)也非常漂亮，但是那個數(shù)據(jù)是被夸大的，實際上無論是養(yǎng)殖企業(yè)，還是飼料企業(yè)，大家在生產(chǎn)實踐中看到的也是同樣的，對嘔吐毒素，對赤霉烯酮的消除，無論用什么樣的方法，在實踐中都非常非常有限。通過這個實驗我們得到的結論是，對常見的霉菌毒素，如果采用吸附劑的方法，對黃曲霉毒素是有效的。這種有效我需要花多少錢能做到的呢?3塊5塊錢的蒙脫石就足夠了，沒必要錢幾十塊錢達到這樣的效果。如果你想把赤霉烯酮和嘔吐毒素有效降低，現(xiàn)在靠吸附的方法是不可能的，是非常有限的，充其量也就是降低20-30，如果你想降低的話唯一的方法就是買好的藥。未來生物技術在脫毒這方面會得到更廣泛的關注。
總結
第一，抗氧化劑含量并不一定等于質量，關鍵是看抗氧化劑效果的評估，好的抗氧化劑的效果才有好的質量。
抗氧化劑說穿了是自己犧牲了，保護了別人(底物)。在純氧的條件下，如果抗氧化能力越強，氧的濃度不會變化。一旦抗氧化劑消化掉了以后，氧開始對底物進行氧化，氧的分壓迅速下降。不同的抗氧化劑加到一個飼料里面或者同一個脂肪里面，表現(xiàn)的效果是不一樣的，有的線平衡達到幾十個小時，我們最長測過能達到30幾個小時。比較差能達到一個小時，半個小時，最差的加了抗氧化劑以后比對照組還要差，這個抗氧化劑就沒有任何意義了，反而起到反作用。這個時候我們就研究出了不同的抗氧化劑拐點的時間。面對眾多抗氧化劑的品牌，我們怎么來選擇，怎么樣能保證飼料不被氧化，迫使我的成本做到最低，我們現(xiàn)在就是采用這樣一個評價的方式來選擇抗氧化劑的品牌和添加量。
現(xiàn)在抗氧化劑不是單一的，把不同的成分進行配伍，結果不同;相同的成份，不同的含量，結果也不同�，F(xiàn)在很多大企業(yè)也在追求平衡點越長，但是帶來了新問題。因為在中國飼料行業(yè)合法的抗氧化劑只有這幾種，實際上其他行業(yè)也用抗氧化劑，比如說汽車的輪胎橡膠高溫高熱，橡膠很容易被氧化，所以輪胎橡膠中有很多的抗氧化劑，這些抗氧化劑是不能食用的。追求抗氧化劑的效果帶來的新的問題，就是有一些抗氧化劑的廠家開始用輪胎橡膠用的抗氧化劑，例如使用2246，這個時候就帶來新的問題--要怎么樣防止出現(xiàn)食品安全的問題。
進口DDGS
實際上進口DDGS的質量是非常成問題的。第一個問題就是美國生產(chǎn)DDGS，不是所有的美國工廠工藝都是一樣的，有離心法和真空法，這兩個方法對DDGS的生產(chǎn)影響特別特別大。第二個是我們現(xiàn)在都是向貿易商購買DDGS很少能有工廠直接進貨，摻假現(xiàn)象很多。
The English version
Industry know mycotoxin problem is China's feed ingredients, feed ingredients, and even the whole world or is one of the biggest problems we met in the process of breeding. About the elimination of mycotoxin, mycotoxins adsorbent is a better method and adsorbent price from a few dollars to several dozens yuan, even hundreds of yuan per kilogram, price difference is so big, in the farming can have the effect that is how much? Here today, I share some simple mycotoxins adsorbent evaluation methods, as well as the additive, fungicide, and so on.
The evaluation of mycotoxins adsorbent
In the Chinese ministry of agriculture of three directories is no mycotoxins adsorbent this clause, the United States also have no, Europe also have no, also does not have the word in the feed industry terms, the word is used only for commercial and academic discussion. Mycotoxins adsorbent on the official has not accepted, the biggest problem is that many enterprises to the ministry of agriculture feed to reaction, said he was in accordance with the mycotoxins adsorbent factory inspection and the suggestion, add the mycotoxins adsorbent, feed is the official selectiving examination, test result is unqualified, the manufacturer of the adsorbent to went to the department of agriculture. The agriculture department specially made explanation to this aspect, because of the adsorbent in the department of agriculture has not been approved, this is the first question.
Second, about the effect of adsorbent, is very popular, mixed reviews. Its evaluation methods have two types of in vivo and in vitro, in vivo evaluation methods is difficult to say clearly to the method of in vitro, all sell mycotoxins adsorbent manufacturers to feed company do propaganda can give very good data, but a scientific approach must be to prove how the mycotoxin feed raw material is transferred, it should be clear, can be confirmed that this evaluation method is effective.
Method is widely adopted by adsorbent manufacturers now is this: basically the mycotoxin sample free, join the buffer solution, and poison adsorbent, through vibration, centrifugal, separation, take the supernatant. I think this data is the biggest benefit of the operation is simple, but it out of the actual situation, because in the process of our feed mycotoxins, or does not exists in the free state of feed ingredients, or free existence is just part of also by combining state is a part of the, if the assessment is to add a sample free of toxins, such data and actual is far.
Some manufacturers have also seen the problem of the previous method, the second method was improved, called blank matrix method. Take a blank substrate, such as corn or starch, it is do not contain any poison, combined with standard sample, actually added some interference, then add them into the buffer thick liquid, after oscillation, centrifugal, also note that reduce toxin in the supernatant fluid is the amount of adsorption. This time we think it is not the same as real raw material situation or, although increased the interference factors, but the data is not very reliable.
A new method for
Base manufacturers to provide us with method now is such, ourselves through these years of groping formed another method, we think the toxins with raw material is adsorption or the binding force, adsorbent must put toxins with the adhesion strength of the raw material of protein or starch eroded, form a kind of combination, this combination in intestinal juice or gastric juice is not parsed, by this way, we'll do a known toxin content of natural substrate, and then combined with adsorbent, by the method of bionic digestive let toxins and adsorbent to form a combination, after separation. Innovation points, this method is the mycotoxins adsorbent added later, can put the toxins can separate, separate the adsorbent in, can clear mycotoxin where to move from the raw material. We almost spent one and a half years to separation method, finally overcome the separation of the difficulty. But now it seems that the recovery rate of adsorbent can achieve 75%, also is not very ideal, remains to be further improved. I think such a toxin transfer process, to make it clear.
In this way, we look at its adsorption of mycotoxin. Select a aflatoxin contamination of cotton pulp, when the gap is measured data, and then add montmorillonite, carries on the in vitro digestion, to separate cotton pulp and montmorillonite, the separated montmorillonite can reach about 80 PPB. After separation, aflatoxin and transferring them to the separation of the adsorbent. Then look at the cattle feed, front is added according to the 5 kg per ton, now there is a way to add, is according to 0.1 kg, 0.3 kg, 1 kg, 3 kg, 5 kg, 7.5 kg, 10 kg, per tonne of feed that according to the proportion of added, without adding former cattle feed is 54 PPB, at the time of adding different proportion, the cattle feed after separation, toxin content decreased obviously, add to 5 kg to 7.5 kg, adsorption data is lower up, are generally in 5 kg, it is a better adsorption.
Different manufacturers of the adsorbent, to aflatoxin, to vomiting toxins, gibberellic ketene, the end result is different, including montmorillonite, adsorption of aflatoxin is more effective, good can do around 70, adsorption of vomiting toxins with gibberellic ketene, according to we make to the effect of this method is very limited, is vomiting toxins good manufacturer can do 25 or so, gibberellic ketene do 20 or so.
The choice of mycotoxins adsorbent
Through these data we can see some? The first is the questions about the toxin adsorbent, although officials have not recognized, but the commercialization of only you can do it, not the other. But there is no accepted standard, evaluation method is directly with the prototype, the buffer is better adsorption effect, the data is also very beautiful, but the data is exaggerated, in fact both farmed enterprise, or feed enterprises, we see the same in the production practice, the vomiting toxins, eliminate to gibberellic ketene, no matter use what kind of method, are very limited in practice. Through the experiments we get the conclusion is that the common mycotoxins, if adopt the method of adsorbent, the aspergillus flavus toxin is effective. This effectively I need to spend how many money can do? Three of the five dollars montmorillonite is enough, don't need the money a few dollars to achieve such effect. If you want to gibberellic ketene and vomiting toxins effectively reduce, now by the method of adsorption is impossible, is very limited, at best, that is, to reduce the 20 to 30, if you want to reduce the only way is to buy good medicine. The future biotechnology in detoxification will get wider attention.
conclusion
First, antioxidant content does not necessarily equal to the quality, the key is to see the antioxidant effect of evaluation, good antioxidant effect is good quality.
Antioxidants, after is his sacrifice, to protect others (substrate). Under the condition of pure oxygen, if the stronger antioxidant ability, concentration of oxygen will not change. Once the digest antioxidants, oxygen began oxidation on the substrate, the oxygen partial pressure drops rapidly. Different antioxidant added to a feed or inside the same fat, the effect of the performance is different, some line balance is a few hours, we tested longest can reach 30 hours. Less able to achieve an hour, half an hour, after the worst added antioxidant is even poorer than the control group, the antioxidant doesn't make any sense, but counterproductive. This time we developed different antioxidant inflection point of time. In the face of numerous brands of antioxidants, we how to choose, how to keep the feed from oxidation, forcing me to achieve the lowest cost, we have now is the way of adopting such a evaluation to select antioxidant brand and add quantity.
Antioxidants are not single now, put the compatibility of different ingredients, different results; The same ingredients, different levels, different results. Now many large enterprises in the pursuit of the longer the balance, but has brought new problems. Because in China feed industry legal there's only several antioxidants, in fact other industries with antioxidants, such as car tyre rubber in high temperature high fever, the rubber is easy to oxidation, so there are many antioxidants in tire and rubber, these antioxidants are inedible. Achieve the effect of antioxidant brought new problems, is some antioxidant manufacturers began in tire and rubber in antioxidants, such as using 2246, this time will bring new problems, how to prevent food safety problems.
Imported DDGS
Actually the quality of the imported DDGS is very problematic. The first problem is that the United States producing DDGS, not all the factory process is the same, centrifugation and vacuum process, these two methods very very big influence on the DDGS production. The second is that we are now buying DDGS from traders rarely have factory direct purchase, many adulteration phenomenon.
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