Nutritional requirements and Feed material selection of Piglet

Piglet nutritional needs and feed raw material selection attachment: you need to log in before you can download or view the attachment. No account number? Register-I'll post it! The core tips for the nutritional needs of piglets and the selection of feed raw materials: the preparation of piglet feed should first consider the digestive physiological factors of piglets themselves. Piglets grow rapidly, material metabolism is exuberant, nutrient utilization ability is strong, but digestive system development is not perfect. Digestive organs are underdeveloped, the volume is small, the function is not perfect, the secretion of digestive enzymes is insufficient, and the digestibility of feed is low. There are certain allergic reactions to antigens in feed, insufficient gastric acid secretion, lack of acidic environment in digestive tract, low inhibition and killing ability to pathogenic bacteria, dominant pathogenic microflora in digestive tract, and piglets are prone to diarrhea. therefore, the preparation of piglet feed requires high technology, and the selection of raw materials should also be in line with the digestive physiological characteristics of piglets. 1 Energy need and raw material selection piglet diet should maintain higher energy concentration and lower crude fiber, generally: digestible energy 14.7~15.5MJ/Kg, crude fiber not more than 4%. In order to achieve such high energy and low crude fiber level, vegetable oil must be added to piglet feed, or a higher proportion of full-fat expanded soybeans must be used in the formula. Glucose and lactose can be used as energy sources for piglets under 7 days old, fructose and sucrose can be used for piglets after 7-10 days old, and pancreatic amylase and intestinal disaccharidase are insufficient for piglets under 2-3 weeks old. Starch can not be used as a source of energy. However, weaned piglets can be based on plant feed and properly add lactose and other ingredients. High-protein whey powder contains more than 12% crude protein and 60%-70% lactose. Its main function is lactose, which is a common energy source for the preparation of early weaned piglets. Due to the limitation of cost and processing technology, 10% whey powder leads to ring mold blockage, generally 3%-8%, and 15%-20% can be added to the powder. The addition of high protein whey powder to the diet of weaned piglets could significantly improve the performance of weaned piglets at 3-4 weeks of age for 2 weeks. Lactose is palatable, easy to digest and absorb (98%), and can produce lactic acid through fermentation, maintain intestinal health of piglets, help digestion and prevent dysentery, and is a good energy source for piglets. The fluidity of lactose is better than that of whey powder, so from the point of view of granulation performance, lactose is a better raw material for suckling pig pellets than whey powder. The lipase activity of early weaned piglets decreased, and the utilization capacity of oil was limited. Studies have shown that the shorter the fat chain, the higher the absorption and utilization rate. Coconut oil has the highest fat utilization rate, followed by corn oil and soybean oil. Lard and butter are the worst. Adding a certain amount of grease is convenient for feed granulation during processing, and adding 5%-6% fat can play a lubricating role in granulation. In recent years, the use of feed emulsifier has greatly improved the utilization rate of oil. Corn is the main energy raw material commonly used. Yellow corn with full grain, no mildew spots and good gloss is selected and puffed before processing. The moisture content should not be higher than 14%, the crude protein content should not be less than 8.5%, and the crude fat content should be 3.5%. With the cultivation of high-protein and high-lysine corn and high phytase corn by plant researchers, the application of corn will have more nutritional value. 2 protein level and raw material selection according to the theory of "ideal protein", the protein requirement of piglets is essentially the amino acid requirement. Studies have shown that piglets are not sensitive to low-protein diets, and the key is to ensure the balance of essential amino acids in diets. Therefore, by adding some amino acids lacking in the diet, when the dietary protein level is low (usually 18%), the amino acids can be balanced and a good feeding effect can be achieved. The first, second, third and fourth limiting amino acids in piglets were lysine, threonine, methionine and tryptophan, respectively. Low-protein diet has the advantages of reducing the incidence of diarrhea and dysentery of piglets, reducing nitrogen emissions from pig farms, and reducing feed costs. Piglets are rich in protein feed sources, such as fish meal, plasma protein powder, soybean protein, expanded soybean meal and so on. In addition, high egg whey powder contains 11%-12% protein, which is also a good source of protein. Soybean contains a variety of anti-nutritional factors and antigenic components that cause immunopathological reactions, resulting in indigestion and diarrhea of piglets. The amount of soybean used in the diet of piglets should be limited, and full-fat expanded soybeans can be used. It is easy to match with a diet with high energy and protein. In the first stage, in addition to high-quality raw materials, extruded soybean meal can be added to the diet, so that piglets can adapt to soybean protein antigen very early before weaning. Skimmed milk powder is also an important protein raw material for early weaned piglets, which not only provides high quality protein (more than 34%). It is also a source of lactose (more than 50%) in early weaned piglets. The active component of plasma protein powder (SDPP) is immunoglobulin, crude protein 70%-78%, lysine 6%-7.6%. Immunoglobulin can improve the survival rate of weaned piglets, reduce the times of dysentery and increase body weight. The contents of methionine and isoleucine in pig plasma protein powder are relatively low, so pay attention to the levels of these two amino acids. High-quality imported fish meal is not only high in crude protein, rich in amino acids and balanced in composition, but also contains unknown growth factors, which is a very effective source of animal protein in piglet feed. Intestinal membrane protein is extracted and concentrated from intestinal mucosa. because it contains the highest digestive enzymes, 65% crude protein and 12% crude fat, it can significantly promote the early maturity and improvement of the digestive system of young animals, and can improve the digestion and absorption of feed. reduce stress, is a high-quality animal functional protein. Extruded soybean meal or extruded soybean plant protein feed usually contains a variety of anti-nutritional factors, such as soybean protein antigenic components-glycinin and β-polyglobulin are the main causes of intestinal damage of piglets and diarrhea after weaning. Limit the amount of soybean meal to no more than 20%. The antigenic components in the protein are partially reduced by soybean meal processing, such as extracting soybean meal or soybean by 60%-70% hot ethanol, or by soybean meal extrusion processing, or by extrusion technology. Fermented soybean meal after enzymatic hydrolysis can effectively reduce the anti-nutritional factors in soybean protein, especially the production of a large number of small molecular polypeptides by fermentation enzymatic hydrolysis is beneficial to the digestion and absorption of dietary protein, which shows a good effect on reducing the diarrhea rate of weaned piglets. Weaning stress can lead to intestinal damage, digestive dysfunction and low digestive enzyme activity, resulting in protein can not be digested and absorbed well, and then decay occurs in the large intestine, and the ammonia and amines produced are toxic to the intestinal mucosa. diarrhea aggravated. Small peptides, especially 2-tripeptides, can be completely and effectively absorbed by piglets, reducing the production of ammonia and toxic amines in the posterior part of the large intestine. At the same time, it can maintain the normal function of digestive tract and reduce the rate of diarrhea. Small peptides can also enhance the reproduction of beneficial flora, improve the synthesis of bacterial protein and improve disease resistance. In addition, some active peptides (such as Exorphines) can promote the development of small intestine of young animals, stimulate the secretion of digestive enzymes, and improve the immune and absorptive capacity of the body. Some studies have shown that small peptides can stimulate and induce the increase of brush margin enzyme activity of small intestinal chorion and promote the nutritional rehabilitation of animals. In addition, the content of lactic acid in fermented soybean meal is 3%, and the content of probiotics is 1 × 107CFU/g. It can be considered that the decrease of diarrhea rate of weaned piglets is the result of the unique quality of soybean meal fermented by special process and a variety of beneficial bioactive substances. (3) the application of additives can be divided into nutritional additives and non-nutritional additives. Nutritional additives include amino acids, vitamins, mineral non-nutritional additives, enzyme preparations, acidifiers, antibiotics, antioxidants, anti-mildew agents, food attractants and so on. With the increase of dietary lysine level, the growth rate and feed utilization efficiency of piglets increased. Other amino acids must maintain proper balance with lysine in order to obtain the best production performance. The content of lysine in high-grade suckling pig feed is 1.4%, methionine: lysine 28 100; threonine: lysine 35 Suzhou 100; isoleucine: lysine ≦ 1:2, glutamine is the most abundant amino acid (8%) in pig milk and is the main energy source for intestinal villus growth of piglets, maintaining the intestinal structure and function of early weaned piglets. After weaning, endogenous glutamine from muscles and blood is insufficient to maintain the integrity of intestinal villi, resulting in villus atrophy, diarrhea and negative feedback inhibition of feeding. The addition of (1 / 2%) glutamine to the diet of piglets is beneficial to the maintenance of normal intestinal function and structure. The application of high copper and high zinc is to control diarrhea and promote growth of piglets. At present, high copper is widely used in piglet feed. Copper supplemented with 250mg/kg in the diet of weaned piglets is generally provided in the form of copper sulfate. At the same time, the addition of iron and zinc should be increased to restrain the toxic and side effects of high copper. As long-term feeding of high copper may cause gastric ulcer, the amount of copper should be gradually reduced in the third stage diet of piglets. Recent feeding practice has proved that the effect of high zinc on controlling diarrhea and promoting growth is better than that of high copper, but they have no additive effect. The amount of zinc added to the feed of weaned piglets is usually 3000mg/kg (provided in the form of zinc oxide). Vitamin B6 should be supplemented to piglets when they are fed a high-protein diet and when they are fed with sulfonamides and antibiotics. Because choline can form methionine in pigs, additional choline supplementation can reduce the need for methionine in pigs. Piglets supplemented with appropriate amount of VC in diet is conducive to rapid growth. The level of calcium in mineral diet should be controlled at 0.58%-0.8%, and the ratio of calcium to phosphorus should be 1.2%. Considering the acidity of feed, the phosphorus source of suckling pig feed can choose calcium dihydrogen phosphate, and the calcium source can choose calcium formate. Antibiotics since the discovery of the growth-promoting effect of antibiotics in the 1950s, antibiotics have been widely used. A large number of experimental results show that the addition of antibiotics can generally increase the growth rate by 10% to 20%, and improve the feed conversion rate by 5% to 10%. The use of antibiotics plays a great role in improving the health level of livestock and poultry and maximizing its growth potential, but microorganisms are easy to develop resistance to antibiotics. With the expansion of the scope of application and the increase of types of antibiotics, its safety has attracted more and more attention. The common acid preparations of acidifiers, enzymes and microecological preparations include citric acid, fumaric acid and propionic acid, which can reduce intestinal value and reduce the proliferation of harmful microorganisms in stomach and small intestine, so as to improve the production performance of piglets. For example, the addition of 2% fumaric acid to the diet of 3-week-old weaned piglets increased the digestibility of energy and protein by 3% respectively, but it was not necessary to add acid to the diet with more dairy products. The purpose of adding enzyme preparation to the diet of piglets is to make up for the decrease of digestive enzyme activity after weaning and to improve the digestion and utilization rate of feed. According to the development in recent years, enzyme preparation has a broad application prospect. Microecological preparation refers to the microorganisms directly fed to animals, which is composed of living natural microorganisms such as lactobacillus, streptococcus, yeast and so on, which can improve the microecological balance in the intestinal tract of piglets and reduce the occurrence of dysentery. Food attraction technology adds a certain food attractant with a special flavor to the feed of lactating sows. Piglets get used to the taste of this ingredient through contact with sows, and they will soon get used to suckling pig feed with the same flavor after weaning, that is, the principle of consistency of flavor between sow feed and suckling pig feed. (4) the effect of processing technology on the feed quality of suckling pigs the key of this technology is to crush all kinds of feed materials to the most suitable particle size for animals, so that the formula feed products can obtain the best feeding efficiency and economic benefits. The control of batching accuracy adopts error-free computer batching control technology, so that the batching of each ingredient can be accurately controlled in each batching. Micro-additives can be premixed and high-precision micro-batching system can be used. Mixing uniformity control this includes the mixing uniformity control technology of formula feed, concentrated feed, additive premixed feed and liquid feed. The selection of appropriate mixer and appropriate mixing time and method is the key to ensure the mixing quality. The first aspect of granulation quality control is to control the quenching and tempering quality of feed, that is, to control the temperature and time of quenching and tempering, the addition of water and the gelatinization degree of starch. the state after quenching and tempering is the most suitable for granulation, followed by the control of hard pellet feed pulverization rate, cooling temperature and moisture, particle uniformity, consistency and water resistance. In order to achieve these requirements, we must be equipped with reasonable steam supply and control system and quenching and tempering, granulation, cooling, screening equipment, and scientifically adjust the control parameters according to the different requirements of the product. The main places for the control of feed cross-contamination are: leakage and mixing in the process of storage; residues in transportation equipment lead to cross-contamination between different products; cross-contamination caused by residues in contaminated silos and buffer hoppers; cross-contamination caused by residues in processing equipment; cross-contamination caused by harmful microorganisms and insects. Therefore, it is necessary to use residue-free transport equipment, silo, processing equipment and correct cleaning, sorting, flushing and other technologies and independent production lines to meet the increasing requirements of feed safety and hygiene.