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1原料生物性因素
即大部分植物原料的生物学属性改变，或品系改良天然抗病力的下降，导致霉菌毒素的产生和污染。例如玉米、小麦、燕麦、大麦、花生等最易滋生9～10种霉菌毒素;大米、高粱易滋生4～5种霉菌毒素;大豆、棉花等易滋生1～2种霉菌毒素。目前我国主要种植的各种玉米尚无抗霉菌毒素品系。
2原料种植过程中的因素
多大数谷物在田间种植期间如果遇到干旱、洪涝的恶劣气候均会产生霉菌毒素。例如玉米在生长过程中要经历播种、分叶、拔节、抽雄、灌浆、乳熟、结实等不同阶段，尤其在后三个阶段期间非常容易因天气变化导致在田间发生霉变。这也就是为什么人们根据毒素污染的阶段将霉菌毒素分为田间毒素和仓储毒素两类。
3原料收获过程中的因素
谷物未完全成熟、机械磨损，昆虫鼠害损伤等均易造成霉菌毒素污染。碎粒及其它谷物废料中的霉菌毒素是整粒谷物的30～500倍。这主要是因为整粒谷物有起保护作用的外层果皮。
4饲料及原料生产储存过程中的因素
值得注意的是，霉菌的孢子总是常规存在于饲料及原料之中，等待适宜温度和湿度，进而萌发并代谢出霉菌毒素。因此在饲料及原料的生产加工和储存过程中对温度、湿度的控制尤其关键。通常玉米的水分含量超过14%，饼粕类水分超过12%即非常容易产生霉菌毒素。另外一个常知的因素温度也会让我们产生误解而犯下错误，大部分霉菌繁殖最佳温度是 25～35 ℃，但是人们忽略的是低温0～10℃同样会有霉菌的繁殖，例如黄曲霉毒素在潮热的环境下容易产生，而像呕吐毒素在0℃就可以产生，玉米赤霉烯酮在10℃时就可以产生。因此产自于北方的谷物原料中一样经常含有霉菌毒素的污染，只是霉菌毒素的种类不同于来自南方的原料。
5饲料销售及使用过程中的因素
饲料厂产品库内堆积、运输到养殖场的装载环节、养殖场的场内存放、畜舍饲喂系统的再污染等因素造成了霉菌毒素的二次污染问题，这也需要饲料生产企业和养殖企业共同重视。
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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