Introduction of mullet species

Scientific name ∶ ChannaStriatus

Malay names ∶ Haruan, Aruan, Ruan, TamanPaya.

English name ∶ StripedSnakebead.

Commonly known as ∶ class fish, snakehead.

Aliases: black fish, money fish, black stick, grouper, snakehead fish, filial piety fish, raw fish, silent head fish and so on.

Black mullet is a valuable freshwater economic fish with large size, fast growth, high yield and economic value.

I. the economic value of mullet

Black mullet is a valuable economic fish with large size, fast growth, high yield and economic value. The local names of mullet are: black fish, rich fish, black stick, grouper, snakehead fish, filial piety fish, silent head fish and so on. Raw fish is a kind of freshwater fish with high economic value, and it is a kind of advanced health food with comprehensive nutrition and delicious meat.

The mullet has few bone spines and the edible rate is 63%. In southern China, especially in Guangdong, Guangdong and Hong Kong and Macao, mullet has always been regarded as a nourishing treasure for those who recover from illness and are frail. Guangdong's well-known "raw fish kudzu soup" is very popular with the general public. Mullet has strong adaptability, rapid growth and convenient transportation. in recent years, with the development of domestic aquaculture and the needs of foreign trade, mullet has gradually become a special breeding species with prosperous production and market. the culture technology of mullet has attracted wide attention.

2. Biological characteristics of mullet

Mullet belongs to the bony fishes, Perciformes, Lepidoptera, Lepidoptera. At present, the main species cultivated in China are Ophiocephalus Argus, Ophiocephalus Argus and their hybrids.

(1) morphological characteristics

1. The morphological characteristics of Ophiocephalus Argus: the front part of the body is cylindrical and the rear part is flattened; the general body length is 25ml 40cm. The head is long, slightly flattened at the front and slightly raised at the back. The body color is grayish black, the back of the body and the top of the head are black, the abdomen is light white, there are irregular black patches on each side of the body, and there are 2 lines of black markings on the top of the head. The dorsal fin is very long, almost connected to the caudal fin, without hard spines, starting above the base of the pectoral fin. The ventral fin is short, the pectoral fin is round, and the tip of the fin extends over the middle of the ventral fin. The anal fin is shorter than the dorsal fin, the caudal fin is round, and the end does not reach the anus. The anus is located in front of the anal fin. The whole body is covered with medium-sized round scales and the top of the head is covered with irregular scales. The lateral line is straight, with a small zigzag above the anus, moving down 2 rows of scales, located in the middle of the body, and extending to the caudal base. Fishermen in the Pearl River Delta region are traditionally called "raw fish in the two lakes". The smell of fish is strong.

2. The morphological characteristics of Ophiocephalus Argus are generally 20cm in length and 500ml / 1000g in weight. The body is nearly cylindrical and the tail stalk is thick and short. The head is long, the kiss is short and slightly flat. The base of dorsal fin and anal fin is very long, without hard spines. The pectoral fin is round, the ventral fin is small, and the anterior position. The caudal fin is round. The body is black and gray, the abdomen is gray and white, with many irregular size black spots; the black spots on the top of the head are in the shape of "188". It is customary to call it "raw fish". The soup with fish has no fishy smell.

3. The main difference between Ophiocephalus Argus and Ophiocephalus Argus is that the body of snakehead is longer and the body of snakehead is shorter; there are seven-star markings on the top of snakehead, and the markings on the top of snakehead are similar to the shape of "188". In addition, the head of Ophiocephalus Argus is more pointed and more snake-like.

4. The hybrid fish was bred by using snakehead snakehead from other places (Shandong, Hunan and other places) as male parent and Guangdong snakehead as female parent. The hybrid grew fast and its body weight was about 1 kg in 3 months. it has the characteristics of strong stress resistance, delicate meat, delicious taste and so on. In the Pearl River Delta region, snakehead is commonly known as "Hong Kong species" and black snakehead is commonly known as "Hunan fish". The offspring of the previous two kinds of raw fish are "hybrids".

(2) Life habits

Black mullet is a benthic fish, which usually lives in still water or micro-flow water with overgrown water and soft sediment, throughout lakes, rivers, reservoirs, ponds and other waters, often diving in the bottom of the water to swing the pectoral fins to maintain balance. Mullet has strong adaptability to the changes of environmental factors in water, especially to hypoxia, water temperature and poor water quality. When the water body is anoxic, it can put its head out of the water and breathe the oxygen in the air directly with the aid of the suprabranchial organ in the Gill cavity. Even in the case of lack of water or even without water, as long as you maintain a certain humidity on the Gill and body surface, you can still survive for a long time. The living water temperature of mullet is 0 ℃-41 ℃, and the optimum water temperature is 26 ℃-28 ℃. When the water temperature reaches more than 8 ℃ in spring, it often moves in the middle and upper layers of the water, and in summer, it often moves in the upper layer of the water. When the water temperature drops below 6 ℃ in autumn, it swims slowly and often lurks in the depths of the water. When the water temperature is too low in winter, it buries the back half of its body in the silt or grass pile, and its head is exposed in the water. Black mullet has a strong jumping ability. When it is hot and stuffy, rain and water rise, the mullet will often jump out of the water and escape along the embankment. When there is an impact of running water, it will often provoke the fish to jump and run away. When escaping, the body will look like a snake and move slowly forward.

(3) feeding habits and growth

Mullet is a typical fierce carnivorous fish. natural fish mainly feed on small fish, shrimp, frogs, tadpoles, aquatic insects and other aquatic animals. Depending on the size and habitat of the fish, the type of food it eats is also different. The fish fry mainly feed on copepods, cladocera and chironomid larvae. When the body length is more than 3 cm, it turns to aquatic insects, and also eats some small fish and shrimp. When the body length is more than 8 cm, it mainly feeds on fish and shrimp. It is worth noting that with the growth of fish, mullet have the habit of killing each other when there is insufficient food or great differences in size. Therefore, culturing mullet should pay attention to consistent stocking specifications, especially in the stage of fry cultivation, multi-stage separate culture should be carried out according to size. Under natural conditions, the growth rate of mullet accelerated before 2 years old, and the growth rate slowed down after 2 years old. Under the condition of artificial feeding, by using expanded feed, the weight of snakehead (Hong Kong species) can reach 10 jin after 4 months of culture in high temperature in summer, and that of hybrids can reach 2 jin after 3 months.