Phosphorus is one of the essential mineral elements in broilers. Because phosphorus in plant-based diets is mainly in the form of phytate phosphorus, phytate phosphorus is difficult to digest and utilize for non-ruminants such as chickens. Therefore, supplementing a certain amount of exogenous phosphorus in the diet is to make up for the animals. The main route required for body phosphorus. However, due to the physiological structure of the chicken, the absorption of phosphorus feed has caused many problems, and this paper will study this issue.
Point:
1. Feed grade phosphorus status
Different phosphorus sources differ in their chemical composition, properties, and ratio of phosphorus to other elements, but there are differences in digestion, absorption, and utilization efficiency. As a conventional source of phosphorus in feed production (accounting for more than 90% of added phosphorus), the use of calcium hydrogen phosphate (DCP) is large, but its price is rising, making DCP a major protein and energy. Raw materials. At the same time, DCP is insoluble in water, and the absorption and utilization rate of active ingredients of animals is low, resulting in an increase in phosphorus excretion to the external environment.
Therefore, the development of phosphorus sources with low added amount, high biological titer and relatively low price has become a hot spot in current phosphorus nutrition research. Calcium dihydrogen phosphate (MCP) is a common mineral phosphorus source used by feed companies in the United States and is currently used in some fish feed production in China. A large number of studies on MCP in foreign countries suggest that phosphorus in MCP is more easily absorbed and utilized than phosphorus in DCP. Dicalcium phosphate (MDCP) is a co-crystal bond of MCP and DCP. It is a new feed additive that combines water-soluble phosphate with cerium-soluble phosphate. The plant-derived calcium hydrogen phosphate (PDCP) is a feed grade calcium hydrogen phosphate obtained by the process of acid hydrolysis, quicklime neutralization and precipitation by the inositol slag in the inositol industrial production. At present, MCP, MDCP and PDCP have not been widely used as feed phosphorus sources in China, and further research work is needed. ,
2. Response of broilers to phosphorus feed
As the most economical source of meat, only broiler chickens have more than 22.7 billion birds in the world in 2016, and they have a significant position in the aquaculture industry. In addition, due to the shortness of the intestines, the laying hens are easy to cause low nutrient utilization rate of the diet, and the concentration of fecal nutrients is high. In addition, the amount of nitrogen and phosphorus excretion in laying hens cannot be underestimated.
For broilers, phosphorus is an essential mineral element in broilers and an essential component of bones and teeth. It is also an important player in maintaining cell function, participating in enzyme composition and metabolism in animals.
Due to the synthesis of eggshells, the demand for calcium and phosphorus is quite different. The calcium content of the diet is higher, the phosphorus content is lower, and the ratio of calcium to phosphorus is much higher than that of non-yield poultry. This requires that the effective feed grade phosphorus content of the diet can only be maintained at a more precise level to facilitate the absorption and utilization of feed grade calcium and feed grade phosphorus. Therefore, changes in feed-grade phosphorus sources and phosphorus levels in laying hens may be more sensitive to the effects of calcium absorption and utilization. In addition, phosphorus is widely involved in the metabolism of nitrogenous substances such as proteins and nucleic acids, and changes in feed-grade phosphorus sources and phosphorus levels may affect nitrogen use efficiency, which in turn affects nitrogen excretion.
At present, the absorption and utilization of phosphorus sources by animals is: “phosphorus source of mineral phosphorus source> plant phosphorus source”, but with the continuous refinement of mineral phosphorus source, the current mineral phosphorus source expands from a single calcium hydrogen phosphate; Calcium dihydrogen phosphate, tricalcium phosphate, etc., wherein the monocalcium phosphate is a eutectic combination of calcium dihydrogen phosphate and calcium hydrogen phosphate, which has a higher water-soluble phosphorus ratio and a lower pH than the conventional calcium hydrogen phosphate. Values, studies have shown that animals have different utilization rates of different mineral phosphorus sources. As a new type of phosphorus source, there are few studies on the difference in utilization of phosphorus sources between broilers and other minerals.
3. Problems facing
The main problems in the use of phosphorus in animal feed are: the shortage of phosphorus resources, the environmental pollution caused by excretion and the low utilization rate of phytate phosphorus by non-ruminants, which all call for the advent of high-quality and high-water-soluble phosphorus source products. This trend has developed rapidly in recent years. With the continuous advancement of phosphorus chemical equipment technology and production technology, the production scale of global feed grade phosphate products has grown rapidly. The product categories have also been updated with market segmentation, from single hydrogen phosphate. Calcium has developed into the current series of monocalcium, dicalcium and tricalcium, and the product type has also evolved from a single powder to fine particles of different specifications. Such as feed grade dicalcium phosphate and Dicalcium Phosphate Granular Feed.
Feed grade phosphorus, as the third most expensive feed ingredient after protein and energy, has received widespread attention and development in recent years. It also plays an important physiological role in the body of animals and is a major source of energy for animal life.