CATDOLL : CATDOLL: Which of the four major freshwater fish is the smartest?

1. Which of the four major fish is the smartest?

I think the most luxurious among the large freshwater fish is the shallowest and most cunning, because they rely on eating small fish for health, so their ability to catch small fish is very strong, and they are always a very smart fish

2. What are the four major fish species in China?

Black carp, grass carp, bighead carp, silver carp

3. Which freshwater fish is delicious?

First is salmon (also known as mandarin fish), which is the best, with few bones and fresh meat. Then there are sea bass, Wuchang fish and bighead carp heads. Next are grass carp, carp, catfish and crucian carp. It also depends on how to cook it, and the craftsmanship is also very important.

4. What are the four major fish species?

China's four major fish species are mackerel, grass carp, silver carp and bighead carp.

1. Black carp

Black carp is one of the four major carps in my country. It is also known as black carp, snail carp, black carp, black carp, black mackerel, black mackerel, copper carp, green stick, and Wuhou carp. It is a large fish in the Cyprinidae and Leucine subfamily. It is distributed in the Yangtze River, Pearl River and its tributaries, the Yellow River, Heilongjiang River and other northern water systems in my country, with a small population. The largest individual in rivers can reach 70 kg, the common individual can reach 15-25 kg, and it can grow to 10-15 kg in ponds.

Black carp lives in the lower layer of water, grows fast, and has delicious meat. It is a farmed fish with high economic value. The food of black carp is mainly snails (including lake snails, lymna snails, etc.) among mollusks. It also eats clams, freshwater shell vegetables, flat snails, etc. Small black carp sometimes also eats bottom-dwelling dragonfly larvae, chironomid larvae, and sedge mosses. In the fry stage, it mainly feeds zooplankton. Because black carp is a carnivorous fish, its intestine is not long, about 1.2-1.4 times its body length. Because mollusks live in the mud at the bottom of the water, black carp has gradually become a bottom-dwelling fish. In recent years, the resources of snails in rivers and lakes have declined significantly. In order to develop black carp farming, many units currently mainly feed artificial compound feeds.

The natural spawning grounds of black carp are widely distributed. The spawning period in the Yangtze River, Xijiang River and Pearl River is from April to June, and slightly later in the northeast. The Yangtze River and Xijiang River are the most prosperous in natural spawning. At present, black carp fry mainly rely on artificial breeding. Selecting mature broodstock and inducing spawning at the right time is the key to good artificial breeding of black carp. The spawning period of black carp is generally from early June to late June, the water temperature is 22-30℃, and the optimum temperature is 25-28℃. The number of eggs carried by black carp is: 13 kg broodstock can reach 1 million eggs; 18 kg can reach 1.57 million eggs; 34 kg can reach 3.36 million eggs.

Black carp grows fast, and a one-year-old fish can reach 0.4-0.5 kg; a two-year-old fish can reach 1.5-2.5 kg; a three-year-old fish can reach 3-4 kg or even more than 5 kg. Due to insufficient feed, black carp is gradually no longer used as the main fish. Except for Jiangsu and Zhejiang, there are not many black carps raised in the north and south, and even fewer in the north. When it is used as the main fish, 60-80 fish are raised per mu. When it is used as a supplementary fish, 10-20 fish are raised per mu. When there is insufficient feed, only 3-5 or 5-10 fish are raised.

2. Grass carp

Grass carp is one of the four major carps in my country, also known as silver carp, grass green, grass root (northeast), 腝, white silver carp, mixed, 腞 (Compendium of Materia Medica). It belongs to the order Cypriniformes and the family Cyprinidae. It is widely distributed, from the northeastern plain in the north to Hainan Island in the south. Grass carp grows fast, has delicious meat and few fine bones, and is loved by the general public. Grass carp is named for its herbivorous nature, has a wide source of feed, is easy to raise, and is very common.

The feeding habits of grass carp vary with each development stage. In the juvenile stage, they feed on animal food. When the fry grows to 1 cm, they mainly feed on small zooplankton. At that time, their intestines also grow accordingly, and they gradually turn to feeding on rotifers, cladocerans, chironomid larvae and other floating crustaceans. Juveniles over 5 cm gradually turn into typical herbivorous fish, but in the early stage (fish seed stage), they mainly feed on duckweed, duckweed and other relatively tender aquatic plants or artificially chopped dry vegetables. Adult grass carp mainly feed on higher aquatic plants, and the types of food they eat are very wide, which varies with the water environment. Usually, grass carp likes to eat bitter grass, verticillata, pondweed, duckweed and tender wormwood the most. In fact, most aquatic plants can be taken by grass carp as food, but some aquatic plants (such as water lilies, water hyacinths, water peanuts, etc.) are not eaten by grass carp. They must be fermented, saccharified or chopped before they can be fed to grass carp. Grass carp likes to eat various dry grasses, such as Pennisetum, Setaria, Echinochloa, etc. Grass carp also likes to eat various artificially cultivated high-yield forage grasses, such as perennial ryegrass, endive, Sudan grass, goose grass, etc. Grass carp also eats various commercial feeds, such as bran, dregs, meal, etc.

The spawning grounds of grass carp are widely distributed. In addition to the Yangtze River, Huaihe River, Pearl River, and Qiantang River, there are also spawning grounds as far north as the Heilongjiang River in the northeast. The spawning season of grass carp in the main stream of the Yangtze River is from late April to late May. The number of eggs carried by grass carp in the Yangtze River region is: 300,000 eggs for a 6 kg broodstock; about 1 million eggs for a 10 kg broodstock. Artificial breeding of grass carp is now popular throughout the country. As long as the broodstock is well cultivated, the effect of artificial estrus of grass carp is good, and the spawning rate, hatching rate, and ponding rate can reach 70%-90%.

Grass carp is the main fish species in many areas. One of the reasons is that the feces of grass carp can be used to fertilize the water and promote the growth of silver carp and bighead carp in mixed culture. When used as the main fish, 80-100 fish are stocked per mu; when used as supplementary fish, 20-30 fish are stocked per mu. The most suitable stocking size is 2-year-old fish (0.25-0.5 kg per fish). Such fish can grow to 1.5-2.5 kg in the same year, and can reach 3-4 kg or even more than 4 kg after another year (3-year-old fish). In the process of raising grass carp, special attention should be paid to feeding and management. In order to reduce diseases such as gill rot and enteritis in grass carp, it is necessary to adhere to the "four determinations" (timing, quantity, quality, and location) of feeding, and timely prevention and treatment of diseases should be carried out. Grass carp likes clear flowing water, so in recent years, grass carp has also been the main species of industrial fish farming and cage fish farming.

3. Silver Carp

Silver carp is one of the four major carps in my country, also known as silver carp, jumping silver carp, silver carp, etc. It belongs to the Cyprinidae and the subfamily Hypophthalminae. It is widely distributed and can grow from south to north in my country.

Silver carp inhabits the middle and upper layers of water. In natural rivers and lakes, the largest individual can reach more than 20 kilograms, and in ponds, the largest individual is 10-15 kilograms. Silver carp has the characteristics of fast growth, few diseases, and no need for special artificial feeding. Therefore, although the meat is not as good as black carp and grass carp, it is still the main fish in pond farming, especially in suburban fish farming, and its output ranks first, especially in ponds in Jiangsu and Zhejiang, where the output accounts for 40%-60% of the total aquaculture output.

Silver carp mainly feeds on phytoplankton (including bacteria attached to algae). In the fry stage (body length of about 15 mm), it feeds on zooplankton and also feeds on artificially fed soybean milk. Silver carp's feeding method is a special type. Its gill rakers are different from those of bighead carp. Each gill raker has a small bony bridge between the adjacent ones, and the outside is covered with a spongy sieve membrane. Therefore, tiny phytoplankton (algae) cannot be filtered out of the body with water and become food. Silver carp is a typical fish that ingests algae. The main components it swallows are various diatoms, dinoflagellates, golden algae, yellow algae, etc. Rotifers, small crustaceans, protozoa, etc. are also found in the intestinal tract. Larger cladocerans and copepods are rarely eaten. In recent years, there have been some new discoveries about the feeding habits of silver carp, namely, detritus and bacteria are very important in the food of silver carp. According to relevant reports, in some ponds with poor phytoplankton, 2-year-old silver carp mainly feed on the detritus of blue algae at the bottom of the pond throughout the summer, and the detritus accounts for 90%-99% of its food weight. When the phytoplankton in the water is very low, or blue algae such as Schizosphaeria micropylis are dominant, silver carp stop filtering in the water layer and switch to feeding mainly on bottom-growing algae.

Silver carp have natural spawning grounds in the Yangtze River, Xijiang River, Pearl River and Heilongjiang River. The reproductive season is from April to May, earlier in the south and later in the north. At present, silver carp fry mainly come from artificial breeding. The silver carp broodstock mature at the age of 3 years. In recent years, some degenerate silver carp have also matured at the age of 2 years. The most suitable age for induced spawning is over 3 years old, with a body weight of 3-6 kg. The number of eggs carried by silver carp is: 4.8 kg for 200,000 eggs; 10 kg for up to 1.7 million eggs.

The breeding of silver carp is quite common, especially in areas lacking forage and snails. Silver carp is the main fish. Although grass carp is the main fish in some areas, the actual stocking number of silver carp is still greater than that of grass carp. Generally, the number of stocking as the main fish is 200-300 per mu, and the maximum number can be 500; when it is used as a supplementary fish, 100-150 or 80-100 per mu are stocked. The general growth rate of silver carp is: the fish can grow to about 13.2 cm in the same year (about 8,000 per mu); the 2-year-old fish grows to about 0.5 kg (if the 2-year-old silver carp is cultivated, it can only grow to about 0.25 kg); the 3-year-old fish can grow to 1.5-2.5 kg. Under the conditions of sparse breeding and intensive breeding, the fish can grow to a commercial specification of about 0.5 kg in the same year. Silver carp are usually fed mainly with feces, grass manure and compost, but some bran, gluten, dregs and other refined feeds can also be added to accelerate growth.

4. Bighead carp

Bighead carp is one of the four major carps in my country. Bighead carp (Aristichthys mobilis) belongs to the Cypriniformes, Cyprinidae, Hypophthalminae, and Bighead carp.