Most fish have no stomachs, only a few have stomachs. Usually, the intestines of fish with stomachs are shorter, while those of fish without stomachs are longer, which allows digestive enzymes to come into contact with food as much as possible, thus digesting some foods that are difficult to digest. It is worth mentioning that stomach-free fish often have to eat constantly, and they will not feel full. If they do not pay attention to controlling feeding, they will easily suffer from enteritis.

1. Carp: Carp is a common food fish, which has strong adaptability and miscellaneous feeding habits, and belongs to stomach-free fish. This kind of fish eats a lot, but its appetite is affected by temperature. It will go into hibernation in winter and not eat. In spring, after Allen Su, it will eat a lot to supplement nutrition.

2. Crucian carp: Crucian carp is widely distributed in China, which is distributed in all major water systems except Qinghai-Tibet Plateau. It grows fast and has low requirements on water temperature, so it is very easy to breed. Although this fish is omnivorous, it mainly feeds on plants and has no stomach.

3. Megalobrama amblycephala: Megalobrama amblycephala is mainly distributed in lakes in the middle and lower reaches of the Yangtze River, and likes to live in still water. It usually inhabits the bottom of the water and feeds on various plants. Because this kind of fish has no stomach, it eats a lot, and its feeding habits are also very wide, and there are many plants that can be eaten.