The second part of my experience in the design of feed formula

The design of feed formula is a very interesting and logical work, and it also contains a lot of dialectical things. A formula does not simply mix several raw materials together, it not only requires an in-depth understanding of animal physiology, biochemistry and organic chemistry, but also memorizes the feeding standards, the types and characteristics of feed raw materials and nutrients in the chest. At the same time, it can flexibly apply feeding standards according to the actual situation. The following is some of my experience when I do the formula in the feed factory, for your reference. 1 must pay attention to the palatability of feed and the quality of raw materials some formulators in the feed formula, just mechanically input all kinds of feed raw materials into the formula software, and then click "linear programming", as long as the nutrition of the formula has reached, print the formula and hand it over to the production and everything will be fine. In fact, this is extremely irresponsible, although the nutrition of the formula has been achieved, but the most important thing is whether the feed "customer" animals like it or not. Because of the poor palatability of the feed, animals will eat little or simply refuse to eat. Therefore, when choosing raw materials, we must choose raw materials that are palatable and fresh without deterioration. Formulators should not just make recipes in front of the computer in the office every day. Every time they make a batch of feed, they must personally check the quality of the raw materials and taste the palatability of the raw materials if necessary. In addition, when the feed is made, it is necessary to test whether the color and smell of the feed are up to the standard. Some feed factories often like to do some anti-stress, increase lean meat rate, promote animal growth of special small materials, because relatively speaking, this small package effect is more obvious, the profit is higher. For example, I once made a small package to control mosquitoes on a farm. The main ingredient of this material is cypromazine, which is mainly used to kill mosquitoes and flies. When making this small material, I didn't notice that the smell of cypromazine was quite bad, but some carriers and antibiotics were added to the formula. As a result, customers reported that pigs refused to eat the feed with this small feed, and later added flavors and sweeteners when adjusting the formula, which has been well received in the market since then. Another similar thing was that some customers complained that one of our company's small materials (mainly composed of xanthamine and xanthamine synergist) was not very effective in promoting growth, and later increased the dosage of sulfonamide and sulfonamide synergist by two times. animals still refuse to eat this small material, the reason is actually very simple, because these drug additives are not good in taste and palatability. When the dosage increases, it is bound to increase the bad smell, so change the amount of sulfonamide and sulfonamide synergist to 1.5 times the original dosage, and add some flavor agents, so that the effect of the formula is much better. It is emphasized that attention must be paid to the quality of feed raw materials, such as rice bran, wheat bran and so on. Fresh rice bran smells fragrant and sweet in the mouth. The green bran shell is generally fresh rice bran, which can be used as much as 50% in duck food. However, due to the high fat content of rice bran, especially in the summer in the south, it is easy to rancidity (about 5 days), so we must pay attention to it when using it in pig feed, because the pig's sense of smell is very sensitive, can not be used as much as possible, can be replaced with cassava. In fact, wheat bran and secondary flour are also a kind of raw materials that are easy to rancidity, but many formulators ignore this point, so when using wheat bran, we should also pay attention to the freshness of wheat bran, or animals will refuse to eat. Fish meal is a good raw material, but the phenomenon of fish meal adulteration (urea, protein essence) is the most serious. Once the suckling pig feed of our company had very strong diarrhea, but it could not be solved by reducing protein and adding zinc oxide and citric acid. Later, we had to take all kinds of raw materials for inspection, and other raw materials were very normal. Only fish meal was found to be mixed with ammonium salt. At that time, the fishmeal in the formula was removed, and the problem of diarrhea was solved immediately. Because the quality of fishmeal is difficult to control, some companies can buy dried fish themselves and then process it into fishmeal. The price of dried fish is 3400 yuan / ton, and the processing cost is 50 yuan / ton, which is cheaper than soybean meal. This kind of fish meal not only reduces the cost, but also ensures the quality. 2 pay attention to the distortion of the formula A good finished feed is determined by many factors, including good feed formula, good raw materials and good processing technology, and so on. An excellent formula is not difficult to make, but due to the actual quality of raw materials, actual processing and other factors, the product can not truthfully reflect the quality of the formula. There are probably the following reasons: the variation of the nutritional composition of ① raw materials, the reason is that even if the same raw material, due to the origin, environment, harvest time, processing, storage and transportation, moisture, mildew degree and so on, its nutritional composition will be very different. Therefore, the quality control department must provide the formulator with accurate data on the nutritional composition of various raw materials. Don't just think that the protein in soybean meal must be 43% or 46%, or 44% or 40%. There is corn, generally speaking, northeast corn protein is relatively low, Henan and Hebei corn protein is relatively high. Do not think that corn is an energy feed and its protein does not need to be tested, because corn uses a large proportion in the feed formula, if the protein is one percentage point lower or one percentage point higher, it will have a great impact on the nutrients in the formula and the cost in the formula. If the actual protein of corn is 8%, and the protein is regarded as 8.7% when calculating the formula, the protein level must not meet the actual nutritional needs of animals. On the other hand, if the actual protein of corn is 8.7, which is regarded as 8.0 when calculating the formula, this formula not only wastes protein raw materials, but also virtually increases the cost of the formula. The influence of various factors in ② feed processing process. Because many formulators are purely animal nutrition origin, the feed processing aspect is considered less, only consider to make the formula, do not consider the impact of processing on the formula. The distortion of formula caused by feed processing is also caused by many factors, including crushing particle size, mixing uniformity, batching accuracy and so on. Because all kinds of animals have different requirements for the particle size of feed, only when the particle size reaches, the animal can achieve the best digestibility. There is also the problem of mixing uniformity, especially the uniformity of premix, if the mixing is uneven, animals may be deficient in trace elements and more likely to be poisoned. In particular, some drug additives, such as Madumycin, normal dose of 5ppm, but more than 6ppm, then the old will cause chicken poisoning, so we need to pay more attention to the impact of mixing and ingredient accuracy, large dosage with large scale, small dosage with small scale, if necessary, use step-by-step dilution, so as to ensure the uniform mixing of drug additives. The feed processing process will also have an impact on the nutritional composition, some formulators say that there will be loss of raw materials in the processing process, which will cause the actual nutritional content of the formula to be lower than the actual content of the formula, so a safety factor will be added when designing the formula. However, some formulators will lower some standards in the formulation, because the moisture in the raw material will be lost in feed processing, resulting in higher nutrients in the feed than in the formula. Each of these two methods has its own rationality, but I think the best way is to take the feed to the laboratory to check the nutrients to see if the formula is distorted. (3) using scientific methods to prepare feed with the continuous development of animal nutrition, the new dietary technology is becoming more and more mature. These techniques include: low protein diet, application of net energy in monogastric animals, preparation of diets with digestible amino acids, protein and so on. The application of these technologies not only reduces the cost of the formula and the amount of nitrogen excreted, but also makes the nutrients in the formula closer to the nutritional needs of animals. In particular, the application of low-protein diet technology in pig feed has been very mature. The protein level of pig feed can be reduced by 3-4% to achieve the same growth performance as that of high-protein diet, but the following points must be paid attention to while reducing protein: the energy and lysine levels of ㈠ low-protein diet must be consistent with those of high-protein diet; ㈡ uses amino acid balance model to prepare diet; ㈢ diet is supplemented with monomer amino acids. The level of essential amino acids in ㈣ mixed meal diet should be corrected by true ileal digestibility of amino acids (pig) or true digestibility of amino acids (chicken). However, for broiler feed, it is difficult to reduce the point by 1-2%, because threonine is the third limiting amino acid in broiler feed. However, some experiments showed that the growth performance of broilers did not decrease significantly when the protein in the diet was reduced by 7% (glutamine was added to the diet). Therefore, low-protein broiler diet should be the focus and focus of animal nutrition research in the future, once successful, its economic value is inestimable. The other is the application of net energy in monogastric animals. when digestible energy or net energy is used, the energy of proteins or fibers is overestimated, while the energy of carbohydrates is underestimated. For example, corn and soybean meal have similar ME and DE, but if you compare their NE, corn NE is 2650 and soybean meal NE is 1940. Therefore, when using DE to design the formula, the formula is unreasonable and uneconomical. However, there is a lack of NE data for all kinds of raw materials, so we can refer to Weizhi's net energy calculator. When using net energy to make the formula, the cost per ton of feed can be reduced by 5-7 yuan. The last technique is to prepare diets with digestible amino acids. To tell you a very simple example, some formulators use 13% soybean meal when making egg duck feed, while others do not use soybean meal at all, but they have achieved the same level of production as high-dose soybean meal diets. what's the reason? The answer is to use digestible amino acids to prepare mixed meal diets. of course, pure corn and soybean meal can easily produce nutritionally balanced diets, but now corn and soybean meal have become sky-high prices. a formulator who uses corn-soybean meal diets all day will inevitably lead to the decline of a feed company. It can be said that the use of digestible amino acid value is the key to the success of the lowest cost feed formula. Because pigs have high requirements for feed palatability, it is impossible for pure miscellaneous meal diets to be used in pig diets. As the taste of poultry is underdeveloped, we can rest assured that we can boldly use the digestible amino acid model, and we should abandon the idea that egg ducks and chickens (ducks) use a lot of soybean meal. There has been a lot of data on the true amino acid digestibility of chicken feed, but there is little information on duck, which is generally referred to as chicken, but this method often underestimates the nutritional value of various raw materials to ducks. because the digestibility of ducks is greater than that of chickens, the formula made with this reference value is usually better than the formula with total amino acid value. (4) the preparation of duck feed meat duck according to the growth characteristics of duck has the characteristics of fast growth rate and high feed reward, and the breeding of duck has developed rapidly in recent years. However, the research on duck nutrition can not keep up with the development of meat duck breeding industry, especially when many formulators make duck feed formula, because there is so little data about duck. Take the metabolic energy of soybean meal alone, duck is 2856Mcal/KG, chicken is 2467Mcal/KG, so it is unscientific to refer to the metabolic energy of chicken feed in the formula. NRC has sufficient data on digestible amino acids in pigs and chickens, but there are few reports on digestible amino acids in ducks, so chicken data must be referred to in order to use digestible amino acids to prepare duck feed. The digestive capacity of ducks is much higher than that of chickens, especially medium-large ducks, whose daily feed intake is about 0.2kg, while that of medium-large chickens is only 0.1kg. Therefore, the feed intake of ducks must be taken into account when preparing duck feed. If the protein of medium chicken is set to 17 and the energy is 3000 Mcal/KG The protein of medium and large ducks can be set to 12.5-16%, and the energy can be set to 2350-2600Mcal/KG, because when we prepare feed, we must consider the problems of egg energy ratio and daily feed intake. The eggs of medium and large ducks can achieve a good production performance as long as they are kept above 45, while the feed intake of ducks is relatively large. Therefore, when setting the energy and protein level of ducks, there can be a large range of variation compared with the nutritional level of broilers. For laying ducks, the maximum egg production rate and egg weight can be obtained when the energy is kept at 2400-2600Mcal/KG, the protein is kept above 16.5, and the lowest energy-to-egg ratio is 70. In short, the design of feed formula is a highly technical and artistic work, it needs a high theoretical level as a guide, it needs accumulated experience, usually only we learn and think more, more practice can make a cost-effective formula. This is an article I wrote in 2007, the result has been afraid to publish, now it seems that some views are very naive, please forgive Dr. Wang. -- Oh, man, I've been waiting for a long time. I clicked on your post, but you deleted it again.-- aren't you always a flirt? Is there any-- a typical flirt? Advertising post-- can you xhwin2000@163.com thank you-- cough? I'm so tired-- can I study? no, xm2107@163.com. Thank you.-can you show me? Qdmsb138@163.com reply gives me a consolation -- it has been re-edited, everyone is sorry. -- write better, learn some-- want to see this stuff for a long time, thank you! Timely rain! But for broiler feed, it is difficult to reduce the point by 1-2% because threonine is the third limiting amino acid in broiler feed. -can't you understand this sentence? Please give me some advice