Introduction of seven unconventional plant protein feeds

In the United States, soybean meal, dried distiller's grains with solubles (DDGS) are still the main protein feed for broilers. In fact, soybean meal is the primary source of protein nutrition for broilers in the world, but it will also be replaced by the second protein feed available everywhere, such as DDGS mentioned above, rapeseed meal (Western Europe) and sunflower meal (Eastern Europe). This paper only introduces the common alternative protein feed.

Where there are advantages in price and quantity, the supply of protein feed is usually small. Once such opportunities arise, broiler producers will be attracted to use these protein rich substitutes, but the results are often disappointing. The main reason is not the quality of these substitutes, but that people do not understand the limitations of each raw material. These limitations stem from the concentration of some anti nutritional factors contained in substitutes, which may vary greatly, and these anti nutritional factors will almost have toxic effects on the metabolism of poultry.

Understanding these anti nutritional factors and their addition level in feed raw materials can enable nutritionists to successfully prepare diets with alternative proteins, and can bring considerable economic benefits to production enterprises.

1 palm meal

In Asia, Australia, South America and Africa, the palm oil industry has developed rapidly, which has led to a large number of palm meal used in livestock and poultry production. The crude protein content of palm meal is not high (the crude protein concentration is less than 18%), but it is still a very popular raw material because it can significantly reduce the production cost of animal husbandry. The contents of methionine and lysine in palm meal are low, and the digestibility is at the average level, but it contains a high level of energy, so it can become an ideal part of the total protein composition of the diet. The crude fiber content of palm meal is also relatively high (20%). Palm meal is comparable to corn bran in many ways. It is speculated that many adverse effects observed in broiler production are caused by the sandy and physical quality of palm meal, not by its nutritional composition.

Therefore, after fully considering the limited nutritional composition, palm meal can be used in broiler diet relatively freely.

2 corn gluten meal

In fact, corn gluten meal will not cause any problems for animal production. It is a by-product formed after starch extraction and processing of corn bran. The crude protein content of corn gluten meal is about 60%, and the digestibility is equivalent to that of corn. It also contains a lot of pigment, so it can make broiler skin deposit a lot of pigment. However, due to the different needs of consumers for chicken skin color, this will lead to the popularity or unpopularity of broiler carcass.

Because the amino acid composition of corn gluten meal is not ideal (lysine content is very low), and it is often used as a source of natural pigment in layer production, resulting in high price, its addition level in broiler feed is limited to a certain extent. Generally speaking, nutritionists do not recommend the use of other protein rich corn feed materials in DDGS based diets, because it will make it more difficult to balance the amino acid composition of the diet. Finally, corn gluten meal cannot be confused with corn bran (crude protein content is 20%), or the mixture of the two can be sold as corn bran (crude protein content is 40%).

3 cottonseed meal

Cottonseed meal is a by-product formed after cottonseed oil extraction. This kind of protein feed is rarely used in broiler production, mainly due to the price rise caused by ruminant feed competition.

Cottonseed meal contains about 40% crude protein, the digestibility is at a medium level, and its main anti nutritional factor is gossypol.

Compared with laying hens, broilers can tolerate higher levels of gossypol, but the addition of cottonseed meal in feed is limited due to its high level of crude fiber (15%). Considering the existence of gossypol, it is feasible to add some iron salts to neutralize gossypol and reduce the side effects of cottonseed meal. Cottonseed varieties with low or no gossypol content can also be used to produce cottonseed meal, which is well tolerated by broilers. Poultry nutritionists suggest that farms gradually use it in broiler diet formula.

4 peanut meal

In some areas where peanuts are produced for human consumption, peanut oil is the main reason for the large amount of peanut meal. Peanut meal is considered as an appetizer feed material for monogastric animals, which mainly contains a certain amount of peanut oil (about 1%).

Peanut meal contains 50% crude protein with high protein digestibility, and also contains some anti nutritional factors (mainly inhibiting trypsin activity), which is similar to soybean meal, but most of the anti nutritional factors have been neutralized in the extraction process of peanut oil.

The main limiting factors of peanut meal used as feed raw materials are the content of fiber and mycotoxin. The former is caused by the extraction of peanut oil, and the latter is mainly aflatoxin. Peanut grows in the soil, and the growth environment is usually warm and humid, so the content of mycotoxin may be very high. Strict monitoring of the quality of raw materials is the ideal solution for the rejection of toxins. Ammoniation and aflatoxin adsorbent in feed are the second ideal solution. Otherwise, peanut meal can be used in broiler diet relatively freely, and even in chicken feed.

5 guar soybean meal

Guar is a leguminous plant, which is widely cultivated in India, Pakistan, parts of the United States and other countries. The main purpose of guar bean is to produce manna galactan gum, which is an adhesive in the paper industry and pigment industry. The residual meal after extracting manna galactan gum from guar beans contains 50% crude protein. The main anti nutritional factor is the residual manna galactan gum, which can be decomposed by adding an appropriate amount of enzyme. The results of guar soybean meal in the field experiment of animal feed are very different, which may be due to its great quality difference. Poultry nutritionists recommend careful use of guar meal in broiler diets until the quality of guar meal is adequately characterized.

6 Lupin

Lupin mainly grows in Australia, is also available in some parts of Asia, and is also cultivated in Britain and Canada. Affected by the cultivated varieties, the crude protein content of Lupin is 32% ~ 42%, and its nutritional value is equivalent to that of soybean. The main limiting factor of lupin in animal nutrition is the level of alkaloids, but modern sweet lupin varieties have significantly reduced the content of alkaloids. In addition, the use of lupin in broiler feed is reduced due to its high crude fiber content (25%) resulting in low energy concentration. A large part of the crude fiber is pectin that can increase the viscosity of chyme in the intestine. The problem of high content of fiber in lupin can be solved by shelling, fine grinding and appropriate addition of enzyme. Unlike soybean meal, Lupin beans do not need heat treatment before use.

7 sesame meal

Generally speaking, sesame meal will not be supplied in large quantities. In addition to containing high levels of phytic acid, sesame meal also contains anti nutritional factors. Its available lysine content is very low and its methionine content is high. It is used by organic poultry producers to benefit from it. Adding a certain amount of sesame shell to sesame meal will affect the quality. In general, the addition amount of sesame meal in poultry diet needs to be further studied and should be used appropriately, especially the calcium and phosphorus in the diet.

The feed materials that can replace soybean meal are far more than the seven kinds discussed in this paper. There are a large number of agricultural by-products and small crops all over the world. Each raw material has its own potential and limitations.

When facing an unknown feed raw material, we should take conservative measures, but professional nutritionists will use appropriate laboratories to analyze the protein feed around us, which can greatly save the production cost of animals.

Generally speaking, it is not recommended to add all these alternative protein materials to poultry opening materials. Not only chicks can benefit from high-quality protein raw materials, but also farms can really achieve the purpose of better cost saving when they are close to the late stage of production when chicken feed intake is at a large level.