Fat is insoluble in water, and more than 90% of animal tissue is composed of water. Therefore, fat must first be emulsified before it can be effectively absorbed and utilized.

1. Insufficient bile acid secretion
Bile salt is a natural emulsifier in animals. But for young animals, they cannot effectively absorb and utilize fat due to insufficient secretion of their own bile salts.

2. Animal species
Poultry special-style broilers, because of the short digestive tract, the residence time of the chyme in the digestive tract is short, and the fat emulsification is not complete. Because of the short digestive tract of aquatic animals, most of them do not have a stomach, and their bile secretion is relatively insufficient. They cannot completely emulsify the fat in the feed, which affects the digestion and absorption of fat.

3. In order to achieve better feeding results, excessive addition of fat in the feed exceeds the emulsification capacity of the animal's own bile secretion, resulting in incomplete emulsification of the fat, and the added fat cannot be fully digested and absorbed.

4. In order to reduce feed costs and use oils with poor absorption and utilization: vegetable fats have a high absorption and utilization rate, but the price is also high. Animal fats are low in price, but their digestibility is low. In actual production, in order to save feed costs, large amounts of animal fats with low digestibility and utilization are used. The digestion and absorption rate of fats is directly determined by the degree of emulsification of fats, so in order to improve the digestion and absorption rate of fats, high-quality emulsifiers must be selected.