CATDOLL : CATDOLL: In a certain aquaculture farm, ammonia was used to clean the pond in mid-May. After 7 days, the toxicity disappeared and silver carp fry were released.

1. A certain aquaculture farm used ammonia to clean the pond in mid-May. After 7 days, the toxicity disappeared and silver carp fry were released.

Add water and dry pond mud, stir and sprinkle evenly over the whole pond. According to the relevant public information, add water and dry pond mud, stir and sprinkle evenly over the whole pond. The purpose of adding dry pond mud is to reduce the volatilization of ammonia. It takes 7-10 days for the drug effect to disappear before the fish and shrimp fry can be put into the pond.

2. How big is silver carp after five months of breeding?

Under good breeding conditions, silver carp fry can reach about 500-800 grams in five months, and can reach about 4-6 catties in the second year. The area of ​​the fish pond for silver carp breeding is best controlled at about 4-8 mu, and the water depth is required to be about 1.5-2m. The pond should be disinfected and fertilized before stocking the fry.

3. The difference between silver carp and bighead carp, what is the suitable depth for silver carp breeding?

Difference in head: Bighead carp has a large head, which is equivalent to 1/3 of its body length; Silver carp has a small head, which is equivalent to 1/5 of its body length.

Color difference: The back of bighead carp is dark brown; the back of silver carp is gray.

Difference in body size: Bighead carp has larger pectoral fins, which extend much beyond the base of the pelvic fins; silver carp has smaller pectoral fins, with the tip of the pectoral fin only reaching the base of the pelvic fins.

Difference in taste: Bighead carp tastes better than silver carp and has higher nutritional value.

1. The difference between silver carp and bighead carp

1. Difference in head: Bighead carp has a relatively large head, which is equivalent to 1/3 of its body length, and its upper jaw tends to protrude forward; silver carp has a relatively small head, which is only 1/5 of its body length, and its lower jaw also protrudes forward.

2. Color difference: The back of bighead carp is dark brown with fine black spots, the belly is grayish white, and the fins are all light gray; the back of silver carp is gray, the belly is silvery white, and the fins are all grayish white.

3. Difference in body shape: Bighead carp's pectoral fins are very large, and much longer than its pelvic fins. Bighead carp's ventral ridge runs from the pelvic fins to the anus, and must be shorter. Silver carp's pectoral fins are very small, and only reach the base of the pelvic fins. Silver carp's ventral ridge runs from the chest to the anus, and is longer.

4. Difference in taste: Bighead carp tastes good and has high nutritional value; silver carp has an average taste and is relatively soft.

2. What is the suitable depth for silver carp breeding?

1. Silver carp generally live in the middle and upper layers of the water body, so when breeding, the pond depth must be at least about 2m. The pond for breeding silver carp must be covered with 200-300kg of decomposed livestock manure or other organic fertilizers on the bottom, and the water transparency must be about 40-60cm, which can promote the growth of plankton in the water and provide food for silver carp.

2. When silver carp is still in the fry stage, it mainly feeds on zooplankton such as rotifers, cladocerans, copepods, etc. When it grows to more than 1.5 cm, it can eat phytoplankton, and occasionally some soy milk, bean dregs powder, rice bran, etc.

4. Is there any difference between silver carp and catfish?

Silver carp (Cyprinidae) Hypophthalmichthys molitrix [local name] silver carp, field carp, flat fish, white fathead, bamboo leaf silver carp, striped carp, sweet potato fish, jumping silver carp, and domestic fish.

It is naturally distributed in rivers in northeastern, central, southeastern and southern China, but there is no natural distribution of silver carp above the Three Gorges of the Yangtze River.

Morphological characteristics: The body is flattened laterally, with a narrow and blade-like bulge from the chest to the anus, called the ventral ridge. The head is about 1/4 of the body length. The body color is silvery white, with a slightly grayish blue on the back. The scales are small. The end of the pectoral fin extends to the base of the pelvic fin. The mouth is wide, with a spiral branchial apparatus above the back of the mouth. The gill rakers are fine and dense, and the gill rakers on the same side are connected to each other to form a spongy membranous sheet, which is conducive to filtering fine food. The intestine is 6-10 times the body length.

Biological characteristics: Silver carp likes to live in nutrient-rich waters with much plankton, inhabits the upper layer of water bodies, is agile and has an impatient temperament, can easily jump out of the net when being caught, and can easily escape upstream when encountering currents.

Feeding habits of silver carp fry is more than 1.5 cm long, mainly phytoplankton, and there is a period of feeding transformation in the middle. Adult fish mainly filter phytoplankton, supplemented by zooplankton. According to the inspection of the food in the intestines of silver carp, the ratio of zooplankton to phytoplankton is 1:248. In addition, crucian carp also feed on the following feed: 10%-60% of the total food), bacteria and dissolved organic matter (formed into food masses through the flocculation of colloids), and artificially fed soybean cake, bran, bran and other commercial feeds.

Silver carp grow very fast. The weight of a 1-year-old silver carp in the Yangtze River reaches 0.49 kg, 2-year-old is 2.03 kg, 3-year-old is 3.5 kg, 4-year-old is 5.31 kg, 5-year-old is 7.62 kg, and 6-year-old is 10.76 kg. The weight growth is fastest between 3 and 6 years old. The silver carp produced in the Heilongjiang and Pearl River basins are smaller. Those grown in the Yangtze River are large and grow the fastest. Under pond breeding conditions, their growth is slower than in natural water bodies. The commercial size of edible silver carp is 0.5-1 kg, and the breeding cycle is 2 years.

Female silver carp in the Yangtze River generally mature at 4 years old and weigh about 5 kg. They mature one year earlier in the Pearl River Basin and one or two years later in the Heilongjiang Basin. Male fish mature one year earlier than female fish. Silver carp weighing 4.5-8.4 kg can carry 630,000-12 million eggs. Its reproductive habits and hatching conditions are similar to those of black carp.

There are about 23,000 species of fish in the world, and there are more than 2,400 species of catfish alone, which means that more than 10% of the world's fish are catfish. Catfish are mainly distributed in tropical areas centered on the equator, but in fact they can be found on all continents except the North and South Poles.

Catfish, scientifically known as catfish, is also known as bearded silver carp, slimy fish, catfish, and fry fish. The distinctive features of this fish are that it has no scales, a lot of mucus on its body surface, a flat head and a wide mouth, and four whiskers on the upper and lower jaws. The best season to eat catfish is between mid-spring and mid-summer.

Catfish is not only rich in nutrients like other fish, but also has tender meat, rich flavor, few bones, is appetizing and easy to digest, making it especially suitable for the elderly and children.

Catfish contains a lot of protein and fat, and has a good therapeutic effect on people who are weak and malnourished.

Catfish is a good product for promoting lactation, and has the effects of nourishing yin and blood, replenishing qi, appetizing, and diuretic. It is a must-have food for women's postpartum diet therapy.