Common feed materials and feed types

First, the quality identification and use ratio of commonly used feed raw materials

Pig is an omnivorous animal, and its feed sources are wide and there are many kinds. The commonly used feeds of pigs include energy feed, protein feed, green feed, roughage, mineral feed and feed additives. The following are some common feed materials for pigs.

(1) Corn

Corn has high energy value, good palatability, no side effects on animals, and is the most commonly used and the largest amount of energy feed, accounting for a larger proportion in the formula, generally 60% to 70%. Maize is prone to mildew when its water content is high, and the mycotoxins produced can cause cancer and animal immunosuppression, which is easy to cause animal poisoning. The normal sensory characteristics of corn are uniform grains, white or yellow, full grains, uniform, no damage, no insect bite, moth and moldy deterioration. In addition, the key to testing corn is the moisture content, the preparation of feed requires that the moisture content of corn does not exceed 14%, otherwise it will greatly affect the quality of feed.

In recent years, due to corn mildew caused by major farms of pig population disease, sow estrus disorder, infertility, abortion, boars poor sexual desire, low pregnancy rate.

(2) Wheat bran

Wheat bran, or bran, is composed of wheat seed coat, aleurone layer and a small amount of embryo and endosperm. Its nutritional value is affected by the flour yield in the process of processing, high flour yield is high crude fiber content of bran, low starch content, and low nutritional value of bran. The effective energy value of bran is not high, the volume is large, and it is commonly used to regulate the energy concentration in the diet. Wheat bran is loose in structure and contains laxative salts, which can stimulate gastrointestinal peristalsis. The general feeding amount is 5%~25%. Because the bran contains high arabinoxylan and so on, if the feeding amount exceeds 30%, it will cause soft stool. At the same time, bran has strong water absorption, and a large amount of dry feeding can cause constipation.

The appearance of good wheat bran is fine debris, the color is fresh and consistent, no fermentation, mildew, caking and odor. Wheat bran is the most commonly used raw material, and adulteration is more likely to occur when it is mixed with cheaper stone flour, rice bran, etc. When identifying, you can insert your hand into the wheat bran and pull it out, if there is white powder on your hand and it is not easy to shake it, it proves that there is stone powder, and then grasp the bran with your hand hard, if the bran is formed into a pure bran, and the hand has the feeling of rising, it is mixed with rice bran.

(3) Soybean meal

Soybean meal is the main source of vegetable protein feed in China, and it is also the best quality feed among all the meal. High protein content, generally more than 40%, excellent quality. Soybean meal contains different levels of urease and antitrypsin due to different processing conditions, thus reducing the digestion and absorption rate of protein and other nutrients, resulting in lower weight gain and lower feed conversion rate of pigs. Although heating can reduce the content of adenase, excessive heating can also lead to the destruction of some amino acids in proteins. The general dietary dosage is about 20%, and adding too much is easy to cause diarrhea in young pigs. The protein content of extruded soybean meal can reach more than 45%, and the urease content is low, the maximum addition amount can reach more than 25%, and there will be no diarrhea symptoms in young pigs.

Good soybean meal is light yellow or light yellow irregular fragments or coarse powder, consistent color, no fermentation, mildew, moth and debris, with normal bean flavor, no other odor. Poor quality soybean meal color is inconsistent, uneven size, caking, mildew, moth and doping, mildew, coke or raw bean taste.

(4) Wheat

Wheat protein content is higher than corn, energy is slightly lower than corn, palatability is better than corn. However, it contains arabinoxylan, B-glucan, phytic acid, lectin and other anti-nutritional factors, and its main anti-nutritional characteristics are high viscosity and water retention, and excessive feeding can cause diarrhea. Generally, it should not exceed 30% of the diet, otherwise it is necessary to add wheat specific enzymes or complex enzymes.

Good wheat after shelled luster, full grain, complete, uniform size, compact organization, no pests and impurities.

(5) Sorghum

Sorghum has a slightly lower nutrient content than corn and a slightly poorer protein. Sorghum contains tannin, has bitter astringency, palatability is poor, when the proportion of sorghum in the diet is large, it will affect the appetite of animals, reduce feed intake and cause constipation. The proportion of pig diet should not exceed 20%.

High quality sorghum, full grain, complete, uniform, compact texture, no impurities, pests and mildew. General kaoliang rice is milky white and shiny.

(6) Fish meal

Good quality fish meal, fat content does not exceed 8%, dry and not caking, water content is not more than 15%, salt content is less than 4%, protein content is more than 60%, amino acid composition balance, rich in lysine, methionine and cystine. Suitable for use with plant protein feed. Due to the high price of fish meal, it is generally used to feed young pigs and breeding pigs, and the amount is less than 10%. Fish meal is easy to be contaminated by fungi and salmonella during storage. Stale fish meal contains a lot of histamine, which can cause pig poisoning. Attention should be paid to detection. In addition, feeding a large amount of fishmeal can make pork with fishy taste, so fattened pigs should stop feeding fishmeal one month before slaughter.

Good fish meal is yellowish brown, yellowish brown, generally uniform particle size, slightly greasy powder, fluffy, fibrous tissue is obvious, containing a small amount of fish eyes, fish scale debris, bone or bone, the hand has a loose feeling, not sticky, not clumpy, has a strong taste of grilled fish, slightly fishy, no caking and mildew, no scorched taste and oil rackness.

(7) Salt

Salt can not only supplement chlorine and sodium, but also improve the palatability of feed, the two generally account for 0.2% to 0.5% of the diet, too much can cause salt poisoning. When the salt in the compound feed is excessive, the drinking water of pigs increases, the feces becomes thin, the gait is unstable, the hind limb paralysis, violent convulsions, affecting the growth, and even death in severe cases; When salt is insufficient, it is easy to lead to decreased feed intake, physical weakness, and pica, such as digging and destroying the circle, drinking urine, licking dirt, and biting each other's tails.

(8) Stone powder

Stone powder refers to limestone powder, natural calcium carbonate, is the cheapest and most convenient mineral feed to supplement calcium. The stone powder contains more than 35% pure calcium, and the magnesium content does not exceed 0.5%. It is generally about 1% of compound feed.

9. Calcium hydrogen phosphate

Calcium hydrogen phosphate can supplement phosphorus and calcium in feed, and the ratio of calcium to phosphorus is about 3:2, which is close to the balance ratio required by animals. It generally contains more than 23% calcium and more than 16% phosphorus. Natural phosphate ores contain fluorine, so it is necessary to strictly control the fluorine content of calcium hydrogen phosphate products. It is generally about 1% of compound feed.

(10) additive premix

Additive premix refers to a uniform mixture of one or several additives (such as trace elements, vitamins, amino acids, antibiotics, etc.) plus a certain number of carriers or diluents, which is fully mixed. It is divided into trace element premix, vitamin premix and compound additive premix. Premix can be used by pig producers to formulate pig diets, and feed mills to produce concentrated feed and full-priced compound feed. Most of the additive premixes sold on the market are compound additive premixes, and the general addition amount is 0.25% to 4% of the full-priced diet, and the specific dosage is determined according to actual needs or product instructions.

Two, commonly used feed types

In order to adapt to the needs of animal production and various animal feeding habits. Compound feeds can often be processed in different shapes and textures.

(1) Dry powder

Dry meal refers to the mixed diet prepared according to the feeding standard, which can be fed directly, and is the main feed type produced by the feed mill at present. The production process of dry powder is simple, the processing cost is low, and it is easy to match with other feeds.

The advantage is to save labor, easy to grasp the feeding amount; The feed is crushed to reduce chewing, increase the contact surface with digestive fluid, promote digestion and improve the utilization rate of nutrients; Can also keep the house clean and dry, the remaining material is not easy to mold, winter does not freeze, easy to eat freely. But dry powder palatability is poor, feeding dust is large, easy to cause respiratory diseases; It is easy to cause losses when eating, which is easy to cause picky eating of pigs, resulting in waste. For pigs weighing more than 30 kg, the particle diameter of 1~2 mm is appropriate, and too fine powder is easy to stick to the mouth, difficult to swallow, affecting food intake.

(2) Raw wet material

Wet feed refers to the dry powder and water mixed in a certain proportion after feeding, the general ratio of feed to water is 1:1. Wet feed can not only improve palatability, but also avoid feed dust. The feeding effect was better, and there was no difference between feeding with dry powder. However, it is required to mix at any time and feed at any time to avoid freezing in winter and spoilage in summer; If the proportion of water is too large, the feed is too thin, which not only affects the dry matter intake of pigs, but also diluts the gastric juice which is not conducive to digestion, and will reduce the growth rate of pigs

And feed conversion rate.

(3) Granular material

Granular material refers to the processing of dry powder into granular form. Pellet feed can improve the palatability of feed, improve nutrient digestibility, facilitate feeding, avoid picky eating of animals, reduce waste, and increase feed intake and utilization rate by 5%~15%. After granulation, the volume becomes smaller, which is convenient for storage and transportation. However, the processing cost of pellet feed is high, and the feed unit price is higher: for Suckling pig feed and teaching trough feed, pellet feed has to go through the crushing process, and too many particles will affect the feeding and digestion of piglet feed.

(4) Liquid feed

Liquid feed is a liquid animal feed refined by suspension technology or fermentation technology from water, corn, molasses, animal and plant protein, trace minerals, vitamins and other raw materials, which can be directly used for feeding liquid full price feed products.

Liquid feed is suitable for sows, weaned piglets, growing pigs and finishing pigs. Compared with the traditional pig diet, it has the flexibility and convenience of feeding. It can improve the feed intake of pigs, easy to digest and absorb, significantly improve the growth performance and reduce the feeding cost; It is beneficial to intestinal health, significantly reduces the pathogenic mortality of weaned piglets, reduces the use of antibiotics, and improves the safety of pork products. There is no dust pollution in the processing process, and the harm to the human body is reduced. However, liquid feed also has some problems, such as unstable quality, large composition difference, large equipment investment, and high technical level of production requirements.

At present, some additives that replace antibiotics such as probiotics, oligosaccharides, small peptides and micro-ecological preparations have similar effects, but most of these additives are expensive, limiting their application in the pig industry. In recent years, foreign liquid feed is heating up again. The application of liquid feed in the European pig industry accounts for about 30%, 30% in Germany, 20% in the United Kingdom, and 30% to 50% in Denmark, Ireland and the Netherlands. In Asia, Thailand and the Philippines are also gradually applying. However, in China's intensive pig production, the feed type is basically still powder and pellet feed, and the research on liquid feed is still an emerging technology, and its production has just started, and people's understanding of its importance is not deep enough.

China's abundant liquid feed resources provide conditions for the large-scale production of liquid feed, China's north (Heilongjiang) rich beet, the south (Guangdong, Yunnan) rich sugarcane, in the process of sugar production will produce a lot of waste molasses, 2.3 million to 2.8 million tons per year; In the central region, there is a large amount of soluble sugar, oil and meat processing waste; In the coastal areas, there are a wide range of fish resources, in the process of fish processing, the inedible part produced by enzymatic hydrolysis can get a large number of liquid feed with the nutritional value of fish meal. These resources are good raw materials for liquid feed, and provide conditions for the further development of liquid feed in China.

With the continuous progress of science and technology, especially the maturity of suspension technology, microcapsule technology and anti-corrosion technology, and the significant feeding effect and economic benefits of liquid feed are recognized by people, liquid feed will have a strong market competitiveness like pellet feed, its types will be more complete, and the application object will be more extensive.