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霉菌毒素污染不单纯表现在饲料上，通风不良鸡舍的空气污染，长时间清刷饮水器的污染等，而鸡群中毒的反应与程度差异又很大，通常会导致鸡群多种难以判断的综合症状，还导致鸡群生产性能下降，免疫机能抑制，抵抗力下降就会疾病多发，而且在临床上由于霉菌毒素隐形的感染，加大了其他疾病治疗的难度，因此这就需要我们加深这方面的认知。
重视霉菌毒素在养鸡生产中的危害。
一般的说，霉菌毒素中毒有急性与隐性之分。急性中毒有明显的临床症状，但发生最多的，人们最容易忽略或难以察觉的则是隐性中毒。要知道隐性中毒所造成的经济损失远比急性中毒要大得多。在急性中毒的病例中，以黄曲霉毒素中毒为最。
隐性中毒主要有以下几个危害层面：
一、对饲料及原料质量的破坏。
孢霉菌属于一种腐生微生物，靠分解、消耗饲料养分生长繁殖，还释放热量，使料温升高，其结果是饲料中蛋白质变质，利用率降低，氨基酸含量下降，还会使脂肪、维生素发生变化，这样一来，按照科学组方设计的全价料，势必变成并不全价以至“残价的料，而饲料在生产、运输、仓储、使用过程中的被氧化及细菌感染，又给霉菌滋生提供了有利条件，导致更多的霉菌毒素产生。此时，饲料及原料的营养浓度已经大打折扣。
二、饲养管理不良情况下的低标准量中毒。
如：高温、通风差、拥挤、粪便清理不及时、免疫反应过强、营养失衡、疾病等会导致畜禽对霉菌毒素的抵抗力下降。由于霉菌毒素是小分子化合物，机体对其不产生抗体，因此，管理不良所致的应激，会使即便是低于危害标准的毒素也会引发动物机体中毒。
三、对畜禽消化道黏膜的强腐蚀性。
会形成鸭雏口腔溃疡，食道炎，鸡和其他动物的肠粘膜脱落、坏死，从而影响机体对营养物质的消化、吸收。例如：会造成VE和硫胺素吸收不良，从而导致免疫力下降和神经症状，又会使肠道形成对色素吸收障碍，引起喙和爪着色不良。
肠道除了是消化器官外又是机体重要的免疫器官之一，其功能是诱导机体对微生物类的抗原发动先天性与获得性免疫反应，肠道同时也吸收霉菌毒素，当霉菌毒素严重破坏了肠道上皮细胞的完整性时，免疫球蛋白的分泌会降低，而免疫球蛋白在肠粘膜的免疫应答中起着至关重要的作用，霉菌毒素的毒性抑制了蛋白质的合成，肠道免疫系统的被破坏会致家禽对传染病的易感性更高了。
四、对肝脏的破坏，造成肝细胞坏死，充血后期形成“橡皮肝 。
肝脏有储备糖原的功能，糖原减少，发生低血糖症，往往饮葡萄糖无效;还会干扰肝脏卵黄前体的合成和运输，进而造成产蛋率下降和产小蛋增多。
五、对肾脏的损伤。
可致肾肿、痛风、软骨组织发育不良，畜禽腿病发病率升高。
六、对血管壁的损伤。
使畜禽血压升高，加重心脏负担和脏器组织渗透压升高，诱发腹水症。
七、对免疫器官的损伤。
除如前所述对肠道免疫系统的破坏外，尤其会造成鸡胸腺、法氏囊的萎缩，T淋巴细胞和白细胞减少，白蛋白和球蛋白含量降低，抗体效价下降，血清抗体浓度降低，引起免疫抑制而使各种病毒病多发。
免疫失败常被认为是疫苗质量，接种过程失误，强毒攻击或其他复杂因素影响，而霉菌毒素造成免疫失败，却常被忽视，很多病在正常免疫后发生，以至于对健康畜禽本不具备感染力的病原也会因霉菌毒素中毒而引发条件性病原感染。有人认为，大量用疫苗后抗体仍达不到应有滴度，很可能与霉菌毒素有关。
八、种鸡采食了被黄曲霉毒素污染的日粮所产后代雏鸡对疾病的易感性增加免疫机能差。
据测定，这种鸡雏在进行新城疫传支常规免疫后其血清抗体滴度显著低于正常鸡水平。而侵入种蛋中的霉菌毒素会导致鸡鸭等禽类孵化死胎率升高，后代幼雏肌胃先天性损伤，促使肠道病早发，并出现生长障碍，此种情况极易与鸡传贫与呼肠孤感染相混。
隐性中毒多呈慢性经过且临床表现不尽相同，多为继发症而非毒素中毒的特定症，这就使得许多时候是以别种病症的诊断来治疗本病。
例如：有些霉菌毒素对蛋鸡生产性能的抑制，在开始的短时间内体现不出来，随着时间推移体内毒素作用积累增多，到中期开始表现直至后期。
曾有一例蛋鸡，在中毒后的发病前期，采食由细慢、叨料到逐渐减少，后发展为拒食而产蛋还在上升，至高峰维持25天后才开始下降。
据分析，这是因为此批鸡育雏育成良好，又正处于产蛋上升期，生殖机能旺盛，而营养的负平衡是在25天后才显现出来，这种表面现象很容易误导诊断，
又如：新生雏鸡1日龄即有明显呼吸道症状，仅10%有肺霉斑变化，这就容易误诊为支原体病，发病于4日龄后的雏鸡，往往生长不良、采食少、体重轻，会被认为是弱雏，霉菌毒素中毒还会使15日龄小公鸡出现打鸣，鸡冠发育过度，这主要是过量玉米赤霉烯酮引起，会被误认为发育早。
再如：赭曲霉毒素中毒主要是肾损伤，表现为利尿作用加强，此时，鸡群多尿脱水，由于利尿水泄，蛋鸡拉稀久治不愈，产蛋下降，肉仔鸡生长缓慢，贫血，形成佝偻症。家畜则出现消化紊乱、采食下降、被毛粗乱、母畜流产、不发情、公畜死精等免疫力低下的还会出现无名高热。
这些表面症状极易干扰临床确诊。因此，在养殖生产实践和兽医临床诊断中，要对霉菌和霉菌毒素的危害有足够的认识，在综合分析中要加入这方面的因素，要关注和积累这方面的经验，对疑似病例要尽可能借助设备手段以提高确诊率，如：病料压片镜检、病料接种培养，这在一般实验室都能做;也可进行生物学鉴定，如：采用可疑病料作动物发病试验，具备相应条件的可采用雏鸭法，这是世界法定通用的方法。
选用1日龄的雏鸭，通过胃管喂给毒素，饲养6-7天后，根据剖检其胆管上皮细胞异常增生的程度来判定，也可取雏鸭肝组织作组织学检查。
对可疑饲料及原料可采用化学分析法进行标准对照测定，也可用把样品放在紫外灯下观察荧光色泽来直观判定，但这需要足够的经验。
由于目前尚无治疗霉菌与霉菌毒素的特效药，常规治疗要配合进行，例如：用制霉菌素、克霉唑的同时在饲料中额外添加能够促进肝脏解毒功能的营养成分，复合VB、蛋氨酸可帮助畜禽加速代谢，排出毒素，VA、VC、VE、硒会缓解霉菌毒素对机体细胞的毒性作用。
用氧化酶制剂可减少毒素在体内的吸收，氧化酶还可破坏毒素分子结构，降低毒素的有害毒性，并能明显促进中毒脏器的排毒、解毒。
一般书刊介绍碘化钾或硫酸铜溶液饮水治疗本病，据实验室检测，要有较高浓度才有抑菌作用，通常1：3000硫酸铜饮水连用3天，临床应用效果不一，有待进一步验证。
坚持预防为主是解除霉菌和霉菌毒素危害的根本。饲料存放要干燥通风，存放期要短。不喂发霉饲料，及时更换发霉垫料，不要图省事，一次添加全天的饲喂量，这在高温高湿的舍内环境中，极易滋生霉菌。畜禽舍要充分通风排湿，饮具用品要洗刷干净，放日光下照射4小时以上，育雏室、孵化室要用甲醛、过氧乙酸消毒，鸡群添换水操作要避免随地洒水，要控制好舍内温湿度。
饲料厂和养殖户自配料，可在新玉米中添加丙酸，以杀灭霉菌，但丙酸对霉菌毒素则没有任何破坏作用，添加一些高效霉吸附剂、分解剂也能起到预防作用，尤其是使用玉米酒糟的饲料，更要注意添加，因为加工一吨玉米可产生约300斤的玉米酒糟，这些酒糟中会浓缩等于三倍量的霉菌毒素。
而用干玉米与新玉米兑掺配料，可以稀释霉菌毒素浓度，只要浓度不超标，就不会有太多危害，况且鸡群对霉菌毒素的敏感程度与日龄成反比，日龄越大的鸡，耐受力较强，而小鸡对霉菌毒素的耐受力低且后继影响更大，这在饲喂中可关注区别对待。
在饲料厂的颗粒料生产过程中，要注意粉碎料入机前更易吸收周围水分，堆压时间过长，仓储通风不良、雨淋、曝晒等都易引发霉菌污染，粉料入机后要调控好蒸气压、水分、时间，还要避免管道冷凝水进入而使粉料水分超标，出机时颗粒料温度、水分过高，也会导致黄曲霉菌生长，还要定期清理颗粒料提升斗或管道中形成的霉积料。
总之，霉菌病和霉菌毒素中毒症的防治是一个动态的连续过程，只有各个环节协同动作，才能收到较好的实效。
The English version
Mycotoxin contamination is not simply turning on the feed, poorly ventilated henhouse of air pollution, for a long time of flush water pollution and so on, and the crowd reaction of poisoning and the degree of difference is very big, again usually cause chickens a variety of difficult to judge the comprehensive symptoms, also led to the decrease of the chicken group production performance, immune function, resistance drop will disease happens, and infection in clinic because of mycotoxin invisible, even more difficult for other diseases, so we must deepen the cognition.
Pay more attention to the hazard of mycotoxins in poultry production.
General said that the mold toxin poisoning with acute and recessive. Acute poisoning has obvious clinical symptoms, but most, the most easy to ignore or imperceptible is recessive poisoning. Want to know the recessive poisoning caused by the economic loss is much larger than acute poisoning. In cases of acute poisoning, most for aflatoxin poisoning.
The recessive poisoning mainly has the following hazard level:
A, damage to the quality of feed and raw materials.
Spore fungus belonging to a saprophytic microbes, to grow by decomposition, feed nutrient consumption, also release quantity of heat, make the material temperature is high, the result is a metamorphic feed protein, utilization rate is reduced, cut down the content of amino acids, still can make change fat, vitamin, as a result, scientific formula design according to full price, it is bound to become is not full and "residual value, and feed in the process of production, transportation, storage, use by oxidation and bacterial infections, and to mould growth provides favorable conditions, lead to more mycotoxin produced. At this point, the feed and raw materials of nutrient concentration has been compromised.
Second, poor management cases, the low standard of poisoning.
Such as high temperature, poor ventilation, crowded, dung cleaning not in time, the immune response is too strong, nutritional imbalance, disease etc. Will cause resistance to mycotoxin decline of livestock and poultry. Because of the small molecular compound mycotoxin, the body does not produce antibodies to its, therefore, improper management of stress, can make even under standard of harmful toxins can also cause the body poisoning animals.
Three, strong corrosive of animal digestive tract mucosa.
Will form the young ducks oral ulcer, esophagitis, chickens and other animals intestinal mucous membrane shedding, necrosis, which affects the body for digestion, absorption of nutrients. For example, will cause the VE and thiamine malabsorption, leading to immune suppression and neurological symptoms, and can make the intestinal form of pigment absorbing barrier, cause bad beak and claws.
In addition to intestinal digestive organs is one of the important organs of the immune body, its function is to induce the body on the antigen of microbial class of congenital and acquired immune response, intestinal also absorb the mycotoxin, when mycotoxin severely damaged the integrity of the intestinal epithelial cells, immunoglobulin secretion reduces, and immunoglobulin in intestinal mucosa plays an important role in the immune response, toxicity of mycotoxin inhibit the synthesis of proteins, the intestinal immune system destruction will cause poultry with higher susceptibility to infectious diseases.
Fourth, the damage to the liver, cause liver cell necrosis, congestion late form "rubber liver.
Liver reserve function of glycogen, glycogen decreased, hypoglycemia, often drink glucose is invalid; Will interfere with the synthesis and transport of liver yolk precursor, and then falling rate and eggs with a small increase.
Five, the damage to the kidneys.
Can cause kidney swollen, gout, cartilage dysplasia, livestock and poultry leg higher incidence of disease.
Six, injury of blood vessel walls.
Increase blood pressure in livestock and poultry, aggravating heart burden and viscera tissue osmotic pressure rise, cause ascites syndrome.
Seven, the immune organ damage.
Except as described above for the destruction of the intestinal immune system, especially cause atrophy of the chicken thymus and bursa of fabricius, T lymphocytes and leukopenia, albumin and globulin content decreased, the antibody titer decreased, serum antibody concentration is reduced, cause immune suppression and make various virus disease happens.
Immune failure often considered quality of vaccine, vaccination process error, strong poison attack or other complicated factors, cause immune failure and mycotoxins, but often neglected, a lot of disease in the normal immune occurred after, so that the health of livestock and poultry should not have infectious pathogen will be conditioned pathogen infection caused by the mold toxin poisoning. Somebody thinks, after used the vaccine antibodies are any drops, probably related to the mycotoxin.
Eight, chicken feed intake of aflatoxin contamination, LiangSuo postpartum chickling susceptibility to disease increase immune function.
According to the measurement, the chicken in the Newcastle disease to spread the serum antibody titers after routine immunization significantly below the normal level of chicken. And invade the breeder eggs of mycotoxin would result in higher hatch chickens, ducks and other poultry stillbirth rates, offspring chicks muscular stomach congenital lesions, prompted the intestinal disease, early and growth disorder, this extremely easily with the poor chicken and intestinal solitary mixed infection.
Recessive poisoning in chronic after more and different clinical manifestations, more for specific disease secondary disease rather than the toxin poisoning, which makes many times with other disease diagnosis to treatment of the disease.
For example: some inhibition of mycotoxin production performance of laying hens, reflect not to come out in a short period of time, in the first place over time, body endotoxin accumulation increased, to the middle of the performance until late.
Had a case of laying hens, the poisoning after the onset of the early feeding by fine slow, where expect to reduce gradually, after the development for refusing foods and egg production is on the rise, peak to maintain 25 days began to decline.
According to the analysis, it is because this batch of brood chicken breeding is good, and is in the egg stage and reproductive function, and the negative balance of nutrition is not apparent until 25 days, the surface is very easy to mislead the diagnosis,
Like: 1 day age newborn chicks have obvious respiratory symptoms, only 10% had lung mould change, it is easily misdiagnosed as mycoplasma disease onset in chicks after 4 days of age, poor tend to growth, less food intake, weight is light, can be considered as weak ones, will cause the mold toxin poisoning 15 age small appear the cock's crow, cockscomb overdevelopment, mainly corn gibberellic ketene cause excessive, will be mistaken for early development.
Or: ochre and aspergillus toxin poisoning mainly kidney damage, characterized by diuresis function strengthen, at this point, the chickens polyuria dehydration, due to the spill, diuresis laying hens diarrhea cured, egg drop, broiler chickens grow slowly, anemia, forming disease rickets. Is a drop in digestive disorders, feeding livestock, thick coat, female abortion, estrus, essence of sire die there will be unknown high fever, such as low immunity.
These symptoms can easily interfere with clinical diagnosis. , therefore, in the aquaculture production practice and veterinary clinical diagnosis, to the harm of mold and mildew toxins have enough understanding, to join in the comprehensive analysis of the factors, to pay attention to and accumulate experience in this field, for suspected cases as far as possible with the aid of equipment means to improve the diagnosis rate, such as: tissue tabletting microscopy, disease vaccination culture, which in general laboratory can do; Biological identification of can also, such as: the suspicious material for animal ill test, have the corresponding condition of goose of cheeper duck method can be used, this is the world's legal generic methods.
Choose 1 day age goose of cheeper duck, through the tube feeding toxin, raised after 6 to 7 days, according to the autopsy to determine the degree of bile duct epithelial dysplasia, also desirable goose of cheeper duck liver tissue for histologic examination.
Suspicious feed and raw materials chemical analysis method can be used to determine standard comparison, also can use the samples in fluorescent colour and lustre is observed under uv lamp to intuitive judgment, but it needs enough experience.
Because there is no the antidote to mold and the mold toxin, conventional treatment to cooperate on, such as: using nystatin, clotrimazole and extra added in feed can promote liver detoxification function of nutrients, composite VB, methionine will help accelerate the metabolism of livestock and poultry, get rid of toxins, VA, VC, VE, selenium would ease mycotoxin toxicity to the cells of the body.
With enzyme preparation can reduce the absorption of toxins in the body, oxidase can also destroy the molecular structure of toxins, reducing toxin harmful toxic, and can obviously promote detoxification, detoxification of poisoning viscera.
General books introduce potassium iodide or copper sulfate solution water treatment of the disease, according to the laboratory testing, should have relatively high concentrations have bacteriostasis, usually 1:30 00 a laparoscope, usually connected to a copper sulfate water for three days, have different clinical application effect, needs further validation.
Insist on prevention is fundamental to lift the mold and the mold toxin harm. Feed store to dry and ventilated, storage period is shorter. Not forage moldy, timely replacement bedding, mould don't graph save trouble, add throughout the feeding amount at a time, in the high temperature and high humidity of the inner environment, cause mould easily. Corral to fully ventilated platoon is wet, drinking utensils supplies to wash clean, let the sun illuminate more than 4 hours, the brood chamber, incubator to disinfect with formaldehyde, peracetic acid, chicken group added in water sprinkling water operation to avoid anywhere, to control the inner temperature and humidity.
Feed mills and producers since the ingredients can be added in the new corn propionic acid, to kill the mold, but the mycotoxin propionate is without any damage, add some efficient mould adsorbent, decomposition agent can also play a role in prevention, especially the use of corn lees feed, more attention should be paid to add, because processing one ton of corn to produce about 300 jins of grains, these grains will be concentrated in the equal to three times the amount of mycotoxin.
And with dry corn and the new corn against the mixing ingredients, can dilute concentrations of mycotoxin, as long as no concentrations exceeding the standards and didn't have a lot of harm, and the crowd to the sensitive degree of mycotoxin varies inversely with age, the greater the day age of chicken, tolerance is stronger, the chicken of mycotoxin tolerance low and subsequent influence is bigger, can focus on this in feeding.
In feed mills in the grain production process, attention should be paid to crush around before feeding into the machine easily absorb moisture, heap pressure time is too long, storage and poor ventilation, drench, insolate easy cause mould contamination, after the powder into the machine to control a vapor pressure, moisture content, time, to avoid pipe condensate water make the powder into the paint, the machine grain temperature, moisture content is exorbitant, can also lead to yellow aspergillus growth, and regular cleaning of grain formed in the ascension or pipeline mould product material.
Anyhow, fungal and poisoning disease prevention and control of mycotoxin is a dynamic process of continuous only each link concerted action, to get good results.
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