Raccoon dog feed and nutrition, lecture 3: fats

In feed composition analysis, all substances that can be extracted with ether are collectively called crude fat, which includes fats, glycerol and lipoid compounds, etc.

Fat is an essential component of the body. For example, the components of mitochondria and the Golgi apparatus in germ cells are mainly phospholipids, nerve tissue contains large amounts of lecithin and cephalin, and blood contains various fats. Skin and fur contain large amounts of neutral fats, phospholipids, cholesterol and waxes, etc.

Fat is the main source of heat energy for the animal body and also the best form of energy storage. When 1 gram of fat is completely oxidized in the body, it can produce about 39 kilojoules (9.3 kilocalories) of heat. This is 2.25 times higher than carbohydrates. Fat is also a good solvent for vitamin A, vitamin D, vitamin E, vitamin K, etc. The absorption and transport of these vitamins all depend on fat.

Fatty acids are important components of fat. They can be divided into two major categories: saturated fatty acids and unsaturated fatty acids. Saturated fatty acids are relatively stable in chemical properties, and the fats they form have high melting points and low iodine values. They are not easily oxidized and are solid at room temperature. The higher the content of unsaturated fat, the more unstable its chemical properties; the higher its content in fat, the higher the melting point of the fat, and the more easily it becomes oxidized and deteriorates.

Those unsaturated fatty acids that are necessary for the life activities of the animal body but cannot be synthesized in large amounts in the body and must be obtained from feed are called essential fatty acids. In fur animal feed, linoleic acid, linolenic acid and arachidonic acid are essential fatty acids. Practice has proved that in the diet during the breeding period, not only protein but also fat must be given attention; essential fatty acids are just as important as essential amino acids.

Fat is extremely prone to oxidative rancidity. Rancid fat is very harmful to the raccoon dog's body. Oxidative rancidity of fat is a chemical reaction process that occurs during storage. Its characteristics are that the fat color becomes noticeably yellower than normal, becomes bitter and develops a special odor. Rancid fat and its decomposition products are very harmful to the raccoon dog's health. Because they act directly on the mucous membrane of the digestive tract, they cause inflammation of the entire small intestine, resulting in serious digestive disorders. The decomposition products of rancid fat destroy various microorganisms in the feed, causing young raccoon dogs to lose appetite. Growth and development become slow or stop, skin health is seriously damaged, and abscesses or skin rashes appear. The quality of the fur is lowered. Raccoon dogs are especially more sensitive to rancid fat during pregnancy, which can cause stillbirth, rotting fetuses, weak offspring and insufficient milk in the mother raccoon dog, and other adverse consequences. Therefore, during feed storage, special attention must be paid to preventing oxidative spoilage of fat.