Pay attention to quality control, rational purchase of pig raw materials

According to the current research, production and application of pig feed in China, from the point of view of the cost performance of feed, lactating sow material and suckling pig material are not easy to pass, and are the two materials that are most difficult to make.

China is accustomed to refer to pigs weighing less than 15kg as suckling pigs. The feed used in this stage is called sucker. With the raising of pig raising level, the accelerated development of the feed industry and the rapid development of large-scale pig farms, the market for suckling pigs has been subdivided into two stages: the high-quality sucker pig feed (also known as the teaching tank). Material) and general sucker feed. It is generally accepted in the industry that chute material refers to the feed to be used within 10 days after the pig is fed from 5 days after its birth; general sucker feed refers to the feed used when the piglets are weaned 10 to 15 kg after weaning.

At present, there are some practical problems in the use of sucker feed. (1) Within one week after using the feed, the pigs will experience reduced feed intake, growth stagnation, and increased diarrhea. To deal with the problem of the connection between ordinary sucker material and high-grade sucker material, do not pull too much of the normal sucker material and high-grade sucker material. (2) There are many high-quality sucker pigs that have solved diarrhea problems, weak seedling problems, and feed intake problems, but the growth rate is not ideal, and the feed payment is also not ideal, so the cost of weight gain is high; (3) Because of many teaching materials The use of high-dose drug additives to control diarrhea has led to a slower rate of long-term growth in pigs that do not use chute materials, switch from regular sucker feed to piglet feed, and eliminate the advantages of slotted feeds! Be very careful.

At present, the standard for good and passing teaching materials should be: (1) Under normal feeding conditions, normal lean type piglets weaned for 21 days) 3 days after weaning, feed intake and growth rate should be restored to pre-weaning (2) From the day of weaning, the rate of nutritional diarrhea was less than 21% within 10 days, the feed conversion rate was about 1.2, the average daily weight gain was about 280g, and the daily feed intake was about 330g; (3) at present Raw material costs, feed costs not more than 5500 yuan / ton. The standard of good general piglet feed should be: After feeding the trough, the feed intake will continue to increase, the growth rate will continue to increase, and the diarrhea rate will not increase; at 42 days, the body weight will reach 15 kg, and the feed remuneration will be around 1.5. According to the current cost of raw materials, the feed cost is not higher than 4,500 yuan/ton. Here we discuss our views on nutritional needs, formulation characteristics, raw material selection, quality control and processing points of suckling pigs.

1 Nutritional characteristics of suckling pigs

The birth weight of piglets is about 1.4kg (different varieties, slightly different), and the growth and development are fast after birth. It is the period with the greatest growth intensity and high feed reward. If the growth and development are blocked at this stage, it is easy to form stiff pigs. Due to the rapid growth and development, many nutrients are needed, especially protein, calcium, phosphorus, and iron metabolism are much higher than those of adult pigs. Sensitive to underfeeding response. Studies have shown that growth in the first week after weaning will have an important impact on the growth performance of a child. Therefore, in addition to the strengthening of feeding management in the first week after weaning of piglets, an important factor is to improve the quality of weaned piglets. Here's a brief talk about the nutritional needs of suckling pigs.

1.1 Energy needs

The ultimate goal of suckling pig rearing is to obtain maximum weaning weight and improve group uniformity. The results showed that piglets with larger weaning weights successfully transitioned to weaning diets and reduced the incidence of nutritional diarrhea; piglets that grew faster during lactation also had faster growth during growth and finishing, Pollmann noted, after weaning Piglets that gained about 900g in 1 week were slaughtered 15 days earlier than piglets that did not gain weight; the studies of Tokach et al. (1992) also showed that piglets that gained more than 225g/d in the first week after weaning at 21 days of age could reach 109kg weight in advance 10 day.

There is a positive correlation between protein deposition and energy intake in suckling piglets. Therefore, to obtain the maximum protein deposition rate, it is necessary to provide maximum energy intake for suckling piglets. Considering that it is necessary to meet the nutritional needs of weak piglets as much as possible, the energy design of the suckling pig feed must not be too high to increase the intake of weak piglets.

After the piglets are born, protein and fat deposits increase rapidly. During the weaning period from birth to 21 days, the protein and fat content of the piglets increased linearly with an average growth rate of 25 to 38 g/d and 25 to 35 g/d, respectively. During the transition from lactation to weaning, protein growth was due to the effects of weaning stress. Slow down, and fat growth is usually negative. During this period, the rate of protein deposition was related to both feed intake and the amount of available protein in the feed. Under good insulation conditions, body fat mobilization rate is closely related to feed intake and the amount of available protein in the diet.

According to relevant data from the United States, the maintenance metabolic energy of suckling piglets needs to be 470kJ/kgBW0.75d, and the metabolic energy needed to maintain metabolism in the first week after weaning (4 weeks of age) is 453kJ/kgBW0.75d, and the second week is 423kJ/kgBW0. 75d. Maintenance of metabolic energy needs of piglets is also related to the ambient temperature. When the ambient temperature is lower than the critical temperature of 1°C, the metabolic energy needs to be increased by 2% to 5%.

Newborn piglets already have higher amounts of pancreatic lipase, but less bile secretion before the age of 3 weeks does not activate pancreatic lipase and emulsified feed fat. At this time, the ability of piglets to digest fat is limited until the stomach of the 16-day-old piglet is only Can digest 25% to 50% of feed fat. The fat in breast milk is in the emulsified state, so its fat utilization rate is high. According to reports, the apparent digestibility of piglets' fat in breast milk is about 95%. After 3 weeks of age, the secretion of bile is gradually increased and the feed fat is increased. The digestion and absorption gradually strengthened. In weaned pigs, the efficiency of ingestion of metabolic energy for growth, protein energy deposition, and fat energy deposition were 0.72, 0.66, and 0.77, respectively, which were close to those of growing pigs.

1.2 Protein and Amino Acid Needs

The growth of piglets is rapid after they are born, physiological changes are rapid, and nutritional needs for protein and amino acids are high. However, the development of digestive system of piglets is not perfect, for example, the trypsin content of piglets is maintained at a relatively low level before 5 weeks of age, and does not begin to increase until 6 weeks of age. Therefore, the dietary protein, especially plant protein, of piglets before 5 weeks of age Digestion and absorption capacity is limited. Post-weaning sources of nutrients shift from breast milk to solid feeds, and high protein levels in diets often lead to diarrhea and growth inhibition in piglets, so it is important to determine appropriate protein levels in the diet of the piglets. Comprehensive studies have reported that 19% to 21% of crude protein levels can meet the needs of 4 to 20kg of piglets. It is recommended that 21% of the 4 to 10kg phase be used, and 19% of the 10 to 20kg phase should be used.

The amino acid requirement of piglets is one of the focuses of research at home and abroad. The amino acids of growing pigs need to be divided into maintenance needs and the need for protein deposition, and the ratio of ideal amino acids for maintenance and protein deposition is different. Because the proportion of amino acids required for maintaining piglets is different from that of growing pigs, amino acid composition of body tissue proteins at different stages is different, and special needs for certain amino acids in piglets, especially for weaned piglets, such as immunity, antioxidation, antistress, and maintenance of intestinal function, Therefore, the ideal amino acid pattern of piglets is different from that of growing-finishing pigs. Actually, it is shown that the requirements of some amino acids are indeed different, such as glutamic acid, threonine, histidine, etc. These have yet to be further explored, and applications can be flexibly controlled with reference to the ideal protein model.

1.3 Mineral needs and vitamin needs

Weaned piglets respond positively to the addition of salt, so NRC increased the need for sodium and chloride in piglets. Potassium, sodium, and chlorine in the diet are interacting, and the electrolyte balance should be considered. In particular, dietary intake of piglets is often high in potassium. Related research reports indicate that the appropriate electrolyte balance for piglets is 200-300 meq/kg.

Although the demand for copper, iron, zinc, and manganese from different studies is quite different, the actual needs may be close. Analysis of possible reasons: 1 different varieties, will be slightly different; 2 the absorption and utilization of trace elements in animals interact with each other, different researchers designed different levels of other trace elements in the basic diet, affecting the needs of the target element research results; 3 part The number of experimental animals studied was too small, and only the requirement quantity obtained from evaluation of growth performance was inaccurate; the design gradient of 4 parts of the experiment was less, which affected the accuracy of the results; 5 the environment was different, and the stress status of pigs was different and may need to be slightly different. Trace elements not only affect piglet growth, but also involve safety and environmental issues. In particular, current piglet feeds generally use high-copper and high-zinc foods, and their trace element content is generally higher than the nutritional needs of piglets. It is still important to further study the needs and proportions of copper, iron, zinc, and manganese in piglets.

The role of high-dose copper and zinc in promoting piglets has been confirmed by a large number of studies, but the problem of residues and contamination caused by high copper and high zinc should be paid attention to. A series of studies have shown that the use of organic chelates can reduce the amount of copper and zinc to achieve the effect of high doses of copper sulfate and zinc oxide. However, actual production may not necessarily be achieved, thus causing some contradictions between production costs and environmental pollution, and we should open up new ideas.

Over the years, a large number of studies have been conducted abroad on the vitamin requirements of pigs. The NRC recommendation for vitamins is based on the minimum requirement for the absence of deficiencies and fails to take into account the need for rapid growth, weaning, immunity, and stress, which are critical for raising piglets. The related research results in the past decade show that: (1) The recommended amount of NRC for fat-soluble vitamins can meet the normal growth needs of piglets, but to obtain the best immune function and antioxidant capacity, it needs 2 to 5 times the NRC requirement. (2) In order to meet the optimal growth needs of piglets, the amount of water-soluble vitamin recommended by the NRC is necessary. In special cases, it needs to be higher. In fact, vitamin supplements in most feeds in China are much higher than the NRC standards, so there are fewer problems in this regard.

2 Feed Preparation Technology and Raw Materials Selection

We must formulate the suckling pig material according to the nutritional needs of the suckling pig and grasp the preparation techniques and characteristics of the suckling pig material. The principles to be considered when selecting some raw materials are: stable supply, quality assurance, and moderate price. For example, small peptides are not very stable in quality and should be selected carefully.

2.1 points to choose energy feed

2.1.1 Corn is the preferred raw material. The quality of corn requires a bulk density of 700 or more, no mildew, and less broken kernels. It is best to use puffed corn, which is about 50% (occupied with corn), but it cannot be used too much, otherwise pigs tend to stick their mouths (for pellets) and affect palatability. There is no standard for expanded corn. Personal experience suggests that the gelatinization rate of expanded corn can reach 88% or more. Corn crushing size can be straightforward 2.0 (straight straight below 1.0, preferably no more than 20%). Secondly, some wheat can be used, and the amount used should not exceed 10%, without adding wheat enzyme preparation.

2.1.2 Whey powder, lactose, sucrose. Whey powder, lactose, and sucrose are also high quality energy sources for sucker pigs. The use of whey powder means the use of lactose. Therefore, the lactose content is very important. The role of milk protein is good, but there is no important lactose; sucrose not only provides energy, but also Can improve the palatability, suckling pigs have a preference for sucrose, its effect is better than saccharin sodium products. In the use of these raw materials to be tempered and mixed, these materials are heat-sensitive raw materials, easy to coke, coking has a negative effect on the palatability of pigs.

2.1.3 Grease. At present, fat is used for sucker pigs. The best fat for suckling pigs is coconut oil, followed by soybean oil, corn oil, lard, beef tallow, and fish oil. Coconut oil is expensive. Soybean oil is a more practical choice. After using a certain amount of extruded soybeans, no fat is used. When using grease, be sure to pay attention to quality. Impurities, moisture, iodine value, acid value, and peroxide value are the indexes that must be measured.

2.2 points to choose protein feed

In the process of selecting protein raw materials for the raw material of the feed for suckling pigs, the digestibility is the first criterion for the selection of protein raw materials, followed by the good ratio and content of amino acids, among which the amino acid that has been mainly considered is lysine. , sulfur amino acids, threonine, tryptophan and histidine. Therefore, when selecting protein raw materials, it is better to choose raw materials with high amino acid content and reasonable ratio. At the same time, due to the limitation of feed intake of suckling pigs, it is necessary to search for protein materials with high nutrient content in order to save space. Under the premise of limited feed intake, as much as possible, the pigs should be provided with diets with high nutrient concentration and good digestibility, so as to ensure that they obtain the ideal daily gain in the piglet stage, and lay the foundation for the entire benefit.

2.2.1 Soybean products. Soybean products are the most abundant source of protein. However, due to their different processing techniques, soy protein products in dairy sow pigs have more selectivity: 1 Extruded soybeans are not only the source of soy oil, but also the source of high quality soy protein. However, the amount of extruded soybeans should not be too large, generally should not exceed 15%. There is no current standard for extruded soybeans, personally think that urease is less than 0.05, digestible protein can be used above 60%; 2 soybean meal, plant protein, its digestibility is often It does not meet the requirements of suckling pigs, but it also contains certain anti-nutritional factors, but it is a common and suitable source of protein for sucking pigs. 3 Soy protein isolates, despite their high protein content, are manufactured using low-temperature soybean meal. There may also be a certain amount of anti-nutritional factors, so the process can be enzymatically degraded; however, since some products undergo enzymatic degradation, it will produce pityriatal peptides and affect palatability, so when selecting, on the one hand, it must be more soluble. Well, on the other hand, we must also ensure better palatability. From the current application of the effect is very good, that is, the price is high; 4 soy protein concentrate, soybean meal soaked in hot alcohol, remove some of the polysaccharides, which is equivalent to the protein concentration, and therefore its value is higher than the ordinary soybean meal , But its digestibility is still limited; 5 Fermented soybean meal, soybean meal after fermentation, digestibility increased greatly, protein content has also increased, anti-nutritional factors have been destroyed. Therefore, fermented soybean meal may be the raw material of the feed for the future piglets. However, due to the different fermentation strains and processes of different manufacturers, the value of milk pig feed differs greatly, and care must be taken when using it. At present, the amount of fermented soybean meal in the suckling pig feed should not be excessive, otherwise it will have a negative effect.

2.2.2 Milk-derived proteins. The main sources of feed protein are mainly high protein content whey powder and whey protein concentrate WPC-34. Its digestibility and amino acid composition are second only to plasma protein powder. If you simply calculate the protein content, the price is not lower than plasma protein powder. Now it is used for human consumption, and its supply is relatively limited, so it cannot be used in a large amount in feed.

2.2.3 Plasma protein powder. Plasma protein powder has advantages in terms of digestible absorption rate, amino acid composition, and the rate of degradation to produce small peptides. It is a good raw material for piglet protein. Especially for homologous plasma protein powders, the effect is better because it is rich in small peptides in itself and is close to the pig's amino acid composition. However, due to the possibility of homologous diseases, care must be taken in the use of this type of raw material. In addition, its high price and unstable supply also limit the use of normalization. If it needs to be used, the dosage should be 3% to have a significant effect, and it is best to use imported from the United States.

2.2.4 Enterostatin (DPS). DPS is also a good source of protein for suckling pigs and works well with plasma protein powders. DPS not only provides high-quality protein, but also prevents weaning stress from damaging the pig's intestinal mucosa. Also, care should be taken in the use of homologous diseases. At present, only US imports can be used, and its prices are also high. In addition, channels and supply are still limited.

2.2.5 Fishmeal. Fishmeal should be the most familiar high-quality protein raw material. When using it, we must measure the freshness, identify the degree of adulteration, and check the physical and chemical indicators. As the quality of fishmeal is really difficult to control, it is recommended not to use more, and the best control is below 2%.

2.2.6 Small peptides. There are many small peptide products currently used in suckling pig feed, which is also the most popular thing in the field of feed nutrition research. Such products should belong to functional protein raw materials. Of course, to mature and stable use for some time, it should be a promising source of high quality protein in the future.

2.2.7 Other protein sources. For example, meat and bone meal, cottonseed meal, rapeseed meal, DDGS, etc. are still under study, and the amount should be strictly limited.

2.3 Selection of Feed Additives

2.3.1 Drug Additives. In our country's rearing environment, the use of drug additives in suckling pig feed must be, according to the relevant regulations and announcements of the Ministry of Agriculture of the People's Republic of China, the currently available drug additives are virginiamycin, bacitracin zinc, and colistin sulfate. Sucirubin, meclizine, mezinol, ernametin, olaquindox, oxytetracycline, chlortetracycline, salinomycin, and the like.

2.3.2 High copper and high zinc additives. When using high copper, do not use high zinc; instead, do not use high copper when using high zinc. In addition, high-copper, high-zinc, and pharmaceutical additives have a synergistic effect. When used, high copper and high zinc doses should not be used at too high a dose, which is not necessary, and can also cause environmental pollution.

2.3.3 Enzyme preparations. Enzyme preparations are very good things, and research and application are continuing to deepen. Since the granulation temperature of the sucker is not higher than 80°C, many enzyme preparations can be used. From the effect of many years of application shows that the effect of the complex enzyme is better than a single enzyme preparation (except phytase).

3 Quality Control and Processing Points

Quality control and processing are very important tasks. Unfortunately, many feed companies do not pay attention. A good formula for suckling pigs, with good raw materials, and without quality control and processing techniques as guarantees, can still not make good sucker feed products. The formulation, raw materials, quality control, and processing are tightly combined to produce a good product. The six indicators for the implementation of the national feed product formulation must be performed by the laboratory of the feed factory. Other key indicators must also be submitted to relevant units on a regular basis. In fact, it does not spend any money or time, but it can receive very good results. For example, the use of zinc sulfate produced in a place, its heavy metal exceeds the standard, inspection once can be. Simply change the supply channel and go to the inspection. The quality control department of the Chia Tai Group is separated from the technical department and it is worth learning.

It is advisable that the piglet feed can also be used to measure starch gelatinization rate, soluble protein, freshness of fishmeal, peroxide value, and some health indicators such as salmonella.

The quality control and processing of suckling pigs are mostly the same as other pigs, and there is not much speciality. Only some heat-sensitive raw materials are used. Particular attention must be paid to controlling granulation temperature and conditioning time. The tempering temperature has a great influence on starch gelatinization. It has been reported that there is a negative correlation between the tempering temperature and the degree of gelatinization, and the greater the difference in temperature between the pellet feed and the pellets, the higher the gelatinization degree.

Piglet pellets can not be made too hard, too hard to seriously affect palatability. Throughout the entire process of feed processing, in addition to feed formulations, the processing techniques that affect the hardness of feed pellets include: raw material sizing process, raw material expansion and expansion process, raw material mixing, water addition, fuel injection process, steam pre-conditioning technology , Selection of molds in the granulation process, post-curing, post-spraying processes, drying and cooling processes. Among them, the steam tempering process, in particular, the effect of quenching and tempering directly affects the internal structure and appearance quality of the particles. The longer the conditioning time, the higher the degree of starch gelatinization and the denser the particle structure after forming, the greater the hardness. Due to considerations of the digestive tract physiological characteristics and feed digestibility of suckling pigs, the gelatinization degree of starch is required to be higher. Therefore, we need to appropriately reduce the hardness of sucker feed by other methods. Therefore, it is very important to choose the appropriate compression ratio ring mode. In general, the pellet ring compression ratio is 6-8. If the bulk of the raw material is used much, the compression ratio is 3, so the material is crisp, but the powder rate is higher.

After the puffed corn and soybeans are crushed, there is generally no problem with the particle size. Other commonly used raw materials are mainly corn and soybean meal. The particle size after crushing has some effects on the digestion and absorption of suckling pigs. In general, milking pigs have better chewing ability than growing and finishing pigs. Whether corn or sorghum, no matter if they are crushed or squeezed, the particle size does not affect the growth rate of piglets. However, tests have shown that the growth rate of barley grain size is 635 microns. Increased by 5% compared to 768 microns, and improved feed utilization, indicating that the size of the size of piglets on the performance of the performance and raw materials are also related. The effect of particle size on the digestion and absorption of nutrients is also related to the interaction between the model and feed varieties. Current research results show that from a comprehensive consideration of various factors, particles are suitable in the range of 400 μm to 600 μm.

If you do the powder, pay attention to the mixing uniformity. Studies have shown that when the coefficient of variation of feed uniformity of piglets decreases from 106.5% to 28.4%, the average daily weight gain increases by 41%, the feed utilization rate increases by 18.52%, and the feed intake increases by 18.33%. Therefore, the feed mixture time of weaned piglets should be After reaching 4 to 6 minutes, the coefficient of variation is not more than 10% according to the standard of our country's compound feed, so as to ensure that the feed is fully mixed and the nutrients are evenly distributed. Therefore, it is best to take two crushing processes (with a good mix, then crush again), so that the product looks like a single raw material to do, but also more uniform.

Recent studies have shown that the gelatinization rate of the particles has a tremendous impact on animal performance. According to statistics, improving the gelatinization rate by 5% to 10% can increase the animal production performance by 3% to 5%, which also has the same effect on sucker feed.