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1原料生物性因素
即大部分植物原料的生物學(xué)屬性改變，或品系改良天然抗病力的下降，導(dǎo)致霉菌毒素的產(chǎn)生和污染。例如玉米、小麥、燕麥、大麥、花生等最易滋生9～10種霉菌毒素;大米、高粱易滋生4～5種霉菌毒素;大豆、棉花等易滋生1～2種霉菌毒素。目前我國主要種植的各種玉米尚無抗霉菌毒素品系。
2原料種植過程中的因素
多大數(shù)谷物在田間種植期間如果遇到干旱、洪澇的惡劣氣候均會產(chǎn)生霉菌毒素。例如玉米在生長過程中要經(jīng)歷播種、分葉、拔節(jié)、抽雄、灌漿、乳熟、結(jié)實等不同階段，尤其在后三個階段期間非常容易因天氣變化導(dǎo)致在田間發(fā)生霉變。這也就是為什么人們根據(jù)毒素污染的階段將霉菌毒素分為田間毒素和倉儲毒素兩類。
3原料收獲過程中的因素
谷物未完全成熟、機械磨損，昆蟲鼠害損傷等均易造成霉菌毒素污染。碎粒及其它谷物廢料中的霉菌毒素是整粒谷物的30～500倍。這主要是因為整粒谷物有起保護(hù)作用的外層果皮。
4飼料及原料生產(chǎn)儲存過程中的因素
值得注意的是，霉菌的孢子總是常規(guī)存在于飼料及原料之中，等待適宜溫度和濕度，進(jìn)而萌發(fā)并代謝出霉菌毒素。因此在飼料及原料的生產(chǎn)加工和儲存過程中對溫度、濕度的控制尤其關(guān)鍵。通常玉米的水分含量超過14%，餅粕類水分超過12%即非常容易產(chǎn)生霉菌毒素。另外一個常知的因素溫度也會讓我們產(chǎn)生誤解而犯下錯誤，大部分霉菌繁殖最佳溫度是 25～35 ℃，但是人們忽略的是低溫0～10℃同樣會有霉菌的繁殖，例如黃曲霉毒素在潮熱的環(huán)境下容易產(chǎn)生，而像嘔吐毒素在0℃就可以產(chǎn)生，玉米赤霉烯酮在10℃時就可以產(chǎn)生。因此產(chǎn)自于北方的谷物原料中一樣經(jīng)常含有霉菌毒素的污染，只是霉菌毒素的種類不同于來自南方的原料。
5飼料銷售及使用過程中的因素
飼料廠產(chǎn)品庫內(nèi)堆積、運輸?shù)金B(yǎng)殖場的裝載環(huán)節(jié)、養(yǎng)殖場的場內(nèi)存放、畜舍飼喂系統(tǒng)的再污染等因素造成了霉菌毒素的二次污染問題，這也需要飼料生產(chǎn)企業(yè)和養(yǎng)殖企業(yè)共同重視。
The English version
1 the raw material biological factors
Most of the biological property change of plant material, or decline in strain improvement of natural disease resistance, leading to the generation of mycotoxin and pollution. Such as corn, wheat, oats, barley, peanut and so on the most easy breeding ground for 9 ~ 10 kinds of mycotoxins; Rice, sorghum breeding ground 4 ~ 5 kinds of mycotoxins; Soybean, cotton, easy breeding ground for 1 ~ 2 kinds of mycotoxin. At present, the main planting of corn is no mycotoxin resistant strains.
Two factors in the process of raw material planting
In the field most of grain crops during if meet some bad weather, drought, floods will produce mycotoxins. Such as corn seeds to experience in the process of growth, leaf, elongating stage, tasseling, different stages such as grouting, milk cooked, strong, especially in the three stages during very easy to mildew in the field as a result of changes in the weather. That is why people according to the phase of toxin pollution will mycotoxin divided into two categories, toxins and storage field toxins.
Three factors in the process of raw material harvest
Grain not completely mature, mechanical wear, insect pest damage mycotoxins are easy to cause pollution. The mycotoxin debris and other grain waste is whole grain, 30 ~ 500 times. This is mainly because the whole grains have the protective outer skin.
4 feed and raw material production factors in the process of storage
It is important to note that the mold spores of routine always exists in feed and raw materials, waiting for the appropriate temperature and humidity, and germination and metabolism of the mycotoxin. So in feed and raw materials production and processing and storage process is especially critical for temperature and humidity control. Usually corn moisture content more than 14%, class cake moisture more than 12% is very easy to produce mycotoxins. Another commonly known factor temperature also can cause misunderstanding and mistake, let us most of the mold to breed the best temperature is 25 ~ 35 ℃, but people ignore is 0 ~ 10 ℃ in low temperature also have mold reproduction, such as aflatoxin in hot flashes under the environment of easy to produce, and like vomiting at 0 ℃ can produce toxins, corn gibberellic ketene can produce at 10 ℃. So come from the north of grains as raw materials in the often contain mycotoxin contamination, only is different from the kinds of mycotoxin raw materials from the south.
5 feed sales and the factors in the process of use
Feed mills product rolls accumulation, transportation to loading link farms, farm field storage, barn feeding system and pollution factors such as the secondary pollution problem of mycotoxin, it also need to feed production and farming enterprises common attention.
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