1. Raw and cooked food

In rural areas, many pig farmers have the habit of feeding cooked food, thinking that cooked food feeding can reduce feed, soften crude fiber, make pigs eat more and improve digestibility. According to experiments, there are differences between raw feed and cooked feed in different feed types. Green feed and coarse feed are better than raw feed, and the digestibility of dry matter and carbohydrate in clinker group is also higher, but there is no significant difference between protein and crude fiber. In concentrated diet, it is better to feed cooked soybean seeds than raw soybean seeds. However, in most concentrate diets, raw feed is better than cooked feed. Generally, boiled concentrated solution will lose 5 ~ 10 of nutrients. The average daily gain of raw feed is higher than that of cooked feed 10, and 0.2 ~ 0.3 kg of concentrate can be saved per kg of gross weight. There is no difference in dry matter digestibility between them, and the protein digestibility of raw feed is higher than that of cooked feed. In addition, feeding pigs with raw materials can save a lot of labor and fuel. However, some toxic or easily polluted feeds, such as rapeseed cake, cottonseed cake, swill, etc., can play a role in detoxification or disinfection after cooking.

2. Thick feed and thin feed

Thin soup can reduce the secretion of digestive juice, accelerate gastric emptying, shorten the residence time of feed in the stomach, and inevitably reduce the digestibility of feed nutrients because of its high water content. Coarse feeding, especially raw dry feeding and wet feeding, can strengthen the chewing function of pigs, promote the secretion of digestive juice, prolong the residence time of feed in the stomach and improve the digestibility of nutrients. It is suggested that coarse materials, dry materials mixed with water or dry materials mixed with green slurry should be extruded and dispersed properly.