How to correctly view "mycotoxins" in animal husbandry industry
With the advent of winter, the use of mold removers is becoming more and more popular, but how to use mold removers, how to use them reasonably, and how much should be used, this should be the most concerned issue as a farmer, but in the market of mold removers In the past, too much profit-seeking sales will not only make people with vague concepts misinterpret the effect of mold release agents, but also cause adverse effects on the health of pigs in the case of unreasonable use.
Mycotoxins are naturally produced by molds. Molds lead to local decay and deterioration during the harvesting and storage of crops. In this process, the toxins produced are called mycotoxins. The toxins produced produce large numbers of propagules (spores) that enter the air and cause diseased infections in the body as the animal feeds and breathes. For example, animal death caused by typical acute flatulence disease also exists because of feed mycotoxin poisoning. Animals are also smart. In the case of mildew in the feed, its feed intake will drop significantly, which is a state of self-protection. When such clinical manifestations occur, it is necessary to check whether the feed is mildewed and so on.
2. What are the hazards of mycotoxins to animals?
The growth of various mycotoxins has different effects on livestock.
Effects of aflatoxin on livestock: growth retardation, decreased feed rate, jaundice, rough coat, hypoalbuminemia, depression, anorexia, acute liver disease, liver cancer, immunosuppression; effects on poultry: bursa and thymus Atrophy, subcutaneous hemorrhage, poor immune response, decreased antibody power, vaccine failure, increased susceptibility to disease, smaller eggs, decreased yolk weight, decreased fertilization rate, hatching rate, and increased embryonic death.
Effects of ochratoxin on livestock: attack on kidneys, immune system and hematopoietic system, liver becomes fragile, mild renal disease, decreased weight gain, severe thirst, growth retardation, azotemia, polyuria, diarrhea, diabetes; Effects on poultry: inhibition of kidney, immune and hematopoietic system, incomplete absorption of calcium and phosphorus, fragile bones, incomplete eggshell calcification, high egg breaking rate, subcutaneous hemorrhage, and easy contusion.
Effects of DON on livestock: damage to the intestines, bone marrow, spleen, reduced feed intake, easy secondary infection by bacteria, vomiting, and refusal to feed; effects on poultry: damage to the digestive tract, glandular stomach and intestinal lesions , decreased feed intake, refusal to feed, and reduced egg production.
Effects of T-2 toxin on livestock: damage to the digestive tract, oral cavity, stomach and intestinal tract, reduced feed intake, irritated oral cavity and skin lesions, food refusal, vomiting, neurological disorders, immunosuppression; effects on poultry : Decreased egg production rate, poor feather growth, oral ulcers, decreased feed intake, food refusal, neurological disorders, suppressed immunity.
Effects of citrinin on livestock: damage to the kidneys, resulting in renal lesions, decreased feed intake, polyuria, soft feces, diarrhea; effects on poultry: inhibition of kidneys, increased urinary excretion, soft feces, diarrhea.
Effects of F-2 toxin on livestock: estrogen hyperactivity, irregular or no estrus, false estrus in gilts, pus before mating, sow labia, uterus enlargement, reduced conception rate, vaginitis, abortion, Stillbirth, valgus legs, red and swollen labia, prolapse of the anus, prolapse of the uterus, and decreased semen quality of boars; effects on poultry: ovarian atrophy, decreased egg production rate, and decreased egg fertilization rate.
Clinical observation: sick pigs generally show normal body temperature or decreased body temperature. Acute poisoning is manifested as a large number of pigs suffering from disease, loss of appetite or even extinction. The pigs died abnormally. The dead pigs generally showed swelling of the stomach, stiff limbs, purple skin and so on. Male sows and growing pigs are seriously ill, die within a few days, and have a high mortality rate. Pregnant sows have a large number of abortions and stillbirths, and boars have dead sperm and no sperm. Chronic poisoning is mainly manifested as abnormal estrus, false estrus, return to estrus, increased proportion of stillbirths and weak litters, unsatisfactory parturition data of breeding pigs; significantly reduced litter size and reduced milk production of sows. Herds have reduced feed intake and slow growth. The vulva of the newborn piglets is red, swollen and weak, and the hind legs are turned outwards in the shape of "splayed feet". The vulva of the growing pig is red and swollen, prolapse of the anus, ataxia, yellow-stained skin, and rough coat. Loss of libido, mammary gland enlargement, foreskin edema, and testicular atrophy in boars. Erythema appears on the skin of the mouth, ears, medial and ventral sides of the extremities, and in severe cases the skin is ulcerated and crusted. Individual pigs vomited significantly. Commercial pigs will have various immunosuppressive diseases, such as blue ear, ring, parapig, etc. The occurrence of such diseases is often caused by mycotoxins. At the same time, it is easy to see the symptoms of vomiting, rectal prolapse, and vulvar swelling in clinical practice. The overall health of the pig herd is in a sub-healthy state, the diarrhea rate of suckling piglets is high, and the antibody test after the vaccine is not ideal, etc., it is necessary to consider whether mycotoxins are at fault. The immune function of the body is decreased, and secondary infection is obvious.
3. How to minimize the impact of mycotoxins on the body, and how to "treat the disease before it is cured"?
1. Selection of raw materials
The origin of high-quality feed raw materials determines the main factor for grain management, which is also the quality requirement of feed processing enterprises for raw material suppliers. Procurement teams of large companies will also make procurement plans based on the degree of mildew of mycotoxins. At the same time, in the process of planting feed raw materials, the quality of the harvest will be reduced due to "force majeure" factors, such as typhoons and floods. This situation is unavoidable, so how to deal with the harmful effects of mycotoxins plays a key role in the requirements of a feed enterprise and the choice of origin.
2. Processing of corn
If the corn is not dehydrated in time after the harvest, it will also cause the growth of mycotoxins. The dehydration of corn is generally based on drying and drying. To do cleaning, there are sieving, washing and other operation methods. Generally, the processing moisture of feed corn is between 14-15 moisture, and corn exceeding this moisture standard is not conducive to storage, transportation or processing.
3. Detailed management of feeding
In the process of feeding, the management is not in place, such as: rushing the pen to wet the feed, the free feeding trough is not cleaned and fed, and the wet feed is not eaten and shoveled away, especially the sow feed trough is not clean. cleaning residue. The reduction of the feed-to-meat ratio can actually be improved through reasonable management. For example, the feed that falls on the ground in slatted farming can be collected and fed to poultry. Before feeding, develop the habit of smelling the odor of the feed and observe the color of the feed. At the same time, in the wet and rainy season, add a mildew remover to the feed to prevent and control.
4. Management of warehousing environment
Unreasonable placement, such as: the feed is placed directly on the ground without a partition in the middle. The warehouse is leaking, the feed is approaching its expiration date, and so on. Such situations must be solved, because this can avoid the production of storage toxins (aflatoxin, ochratoxin); after the feed is bought back, in addition to reasonable storage arrangements, it must also be combined with the actual situation of the pig herd. Do a good job in the prevention and control of mycotoxins.
5. The frequency of feeding corn is best controlled within 2 weeks, not more than one month;
6. Add a really effective mold remover in the process of raising pigs. The principle of mold release agent, one is clay adsorbent, which uses the ionic polarity formed by the tetrahedral interlayer porous structure and the surface to strongly adsorb mycotoxins that also have ionic polarity. The strong adsorption force comes from the large surface area and Electrostatic adsorption; the second is yeast cell wall extract: using the chemical structure of glucomannan in the yeast cell wall and the affinity of mycotoxins that also belong to the organic category.
4. How to reasonably degrade the effects of mycotoxins on animals?
1. Application of feed mildew inhibitor
The use of antifungal agents is mainly used in grain storage, because the starch resistance of corn needs to be transformed for a period of time, and the content of resistant starch is highest in the new harvest period, which in turn reduces the digestion and absorption rate. Therefore, feed processing enterprises generally choose natural dry corn to process into piglet feed. For the storage of natural dry corn, the most important point is the prevention and control of mycotoxins, and the common method is to add the application of antifungal agents. The main activity of the antifungal agent is mainly the organic acid in the non-dissociated state. Antifungal agents include propionic acid and its salts, fumaric acid and its salts (mainly dimethyl fumarate), sodium diacetate (sDA) and other organic acids such as formic acid, propionic acid, lactic acid, sorbic acid , citric acid, benzoic acid and their salts . The fungicides currently on the market are mainly mixtures of the first three or more.
Proper use of antifungal agents can prevent mildew in the feed, but when used improperly, it will not only fail to prevent mold, but also damage the quality of the feed, and even cause harm to the health of livestock, poultry and people. Be sure to pay attention to the following issues when using:
(1) Antifungal agent can only inhibit the growth of mold but cannot eliminate the mold that has been produced, so it is best to add antifungal agent when the feed and raw materials are not moldy. Feed manufacturers generally add antifungal agent to the feed to do a good job. To ensure the quality of the shelf life, adding a mildew remover (Mumeiqing or Chumoubao) is a preventive measure based on the actual situation to find the existing mildew;
(2) Pay attention to safety, add in strict accordance with the recommended amount, and add antifungal agents based on the principles of low toxicity, low cost and good effect;
(3) Each antifungal agent has its own suitable antifungal range, and the mixed use of multiple antifungal agents is more effective than using a single antifungal agent;
(4) If one antifungal agent is used for a long time, the bacteria will develop drug resistance, so a variety of antifungal agents should be used in rotation;
(5) Most antifungal agents are acidic substances and cannot be mixed with alkaline substances, otherwise the efficacy of antifungal agents will be reduced;
(6) Strengthen management to prevent mildew of feed. Mix well with feed when using mold inhibitor.
There are other measures to prevent mold in market feed:
(1) Control the water content of the feed and keep the environment dry. When the moisture content of cereal feed is 17%-18%, it is the most suitable condition for mold growth and reproduction. Therefore, the crops should be dried quickly after harvesting, and the drying must be uniform and uniform. The moisture content of corn, sorghum and rice should be controlled below 14%, the moisture content of soybeans and their meal, wheat and bran should be controlled below 13%, rapeseed meal, cottonseed meal and peanut kernel meal should be controlled under 13%. , fish meal, meat meal and meat and bone meal water content should be controlled below 12%.
⑵ physical mildew method. Mainly include temperature control of storage environment, closed oxygen barrier storage, controlled atmosphere storage, low temperature ventilation storage and radiation method.
Application of mold remover
At present, the mature mold release agents used in the market are mainly mineral adsorbents and yeast cell wall extracts (mannose oligosaccharide and glucan).
1. Mineral adsorbents: mainly hydrated aluminosilicate, montmorillonite, bentonite, among which hydrated aluminosilicate has been confirmed by the US FDA as a mold release agent in food and feed, and these products are of good quality The key to the bad is the purity of the product. The lower the purity, the worse the adsorption selectivity, which will affect the content of vitamins, amino acids and trace elements. It has a strong adsorption effect on polar aflatoxin. The disadvantage is that the dosage is large. According to relevant data reports, 3kg should be added per ton of feed. At the same time, it also has an adsorption effect on polar vitamins and amino acids. When adsorbing aflatoxin, it also takes nutrients out of the body.
2. Yeast cell wall: mainly mannose oligosaccharide, which adsorbs part of mycotoxins through electrochemical action, but its adsorption effect is significantly lower than that of mineral products. In vivo experiments, the symptoms of animal mycotoxins cannot be relieved alone. The disadvantage is that it cannot adsorb non-polar zearalenone, falomycin and vomitomycin, which are the most harmful to sows. For various toxins that have been absorbed into the circulatory system by the intestinal mucosa, it cannot fundamentally solve the mycotoxin poisoning of the main feed. Therefore, the effect is not good in the case of clinical reactions to mycotoxins.
3 Simple determination of the quality of mineral adsorbents:
1. The fineness of high-purity montmorillonite is more than 300 mesh, and the production cost is relatively high. Ordinary bentonite and zeolite powder are generally only within 100 mesh, and the cost is low. Therefore, when you touch it by hand, you can feel that ordinary bentonite and zeolite powder are rough, while high-purity montmorillonite feels fine and smooth.
Second, montmorillonite has strong water absorption, put your hand in it, the moisture on the skin will be absorbed instantly, and then the hand will be exposed to the air, there will be obvious burning sensation. Bentonite and zeolite powder do not have such characteristics.
Regarding the application of mold remover, it can be concluded that for the routine prevention of mycotoxins, yeast cell walls can be selected; for mold poisoning treatment, minerals can be selected, and it is best to use minerals during seasonal humidity. Classes are more practical.
3. Application of detoxification products
Decomposing molds: The active ingredients are active enzymes such as aflatoxin decomposing molds, which can decompose some mycotoxins in a targeted manner. However, due to their strong requirements on temperature and environment, their stability is not good, and only for one type of mold. Toxins are expensive, and the toxicity of the decomposed products to the body needs to be studied.
Chinese herbal medicines: mainly by improving the liver's ability to detoxify toxins to achieve the purpose of removing mycotoxins. And according to the clinical thinking of traditional Chinese veterinarians, mycotoxin poisoning is only a poisoning reaction. It is treated by combining Chinese herbal medicine according to specific clinical reactions, not just using a certain prescription to relieve or alleviate mycotoxin poisoning. treatment purpose. At the same time, there are also many studies based on the data extracted by the single prescription drug laboratory, but the clinical manifestations are different or because of the type of breeding animals, the incentives of the disease are mixed with other factors, the TCM veterinarians need to take into account the above situations. Prescribing medicines also reminds Chinese veterinarians that they are rigorous in judging diseases and increase their confidence in the efficiency of medicines. And in the long-term use of Chinese herbal medicine for health care, the detoxification reaction of the body's internal environment is also invisibly moved, thereby gradually improving the health of the pig herd. This is why foreign pig breeds are introduced in the process of breeding and cultivation The excellent genes of Chinese pig breeds. I think one of them may be the importance of the disease resistance genes of our pig breeds.
Although mycotoxins are ubiquitous and affect the development of our aquaculture industry, modern scientific research combines the unique experience of ancient medical research in my country, and then develops into the application of aquaculture industry. Then we can greatly reduce the indirect or direct economic losses caused by mycotoxins in the breeding industry, minimize the harm of mycotoxins as much as possible, and also speed up the economic development of my country's animal husbandry industry.