CATDOLL : CATDOLL: How many months does it take to raise grass carp before it can be sold? How to raise grass carp

Generally, grass carp needs to be farmed for about 24-36 months before it can be sold, and can only be put on the market after it reaches the standard of commercial fish. 1. The body length of winter-aged grass carp is usually about 34 cm, and the weight is usually about 0.75 kg. 2. The body length of winter-aged grass carp is usually about 60 cm, and the weight is usually about 3.5 kg. 3. The body length of winter-aged grass carp is usually about 68 cm, and the weight is usually about 5 kg. 4. The body length of winter-aged grass carp is usually about 74 cm, and the weight is usually about 7 kg.

1. How many months does it take for grass carp to be sold?

1. Grass carp breeding cycle

(1) Grass carp generally needs to be farmed for about 24-36 months before it can be sold (factors such as farming density and management methods will affect the time to market), and it can only be put on the market after it reaches the standards of commercial fish.

(2) Grass carp grows very fast. Its body length increases fastest at 1-2 years old, and its weight increases fastest at 2-3 years old. After entering the 4th age (when it has reached sexual maturity), its growth rate decreases significantly.

2. Grass carp weight

(1) At the first winter age, the body length is generally about 34 cm and the weight is generally about 0.75 kg.

(2) At the 2nd winter age, the body length is generally around 60 cm and the weight is generally around 3.5 kg.

(3) At the age of 3 winters, the body length is generally about 68 cm and the weight is generally about 5 kg.

(4) At 4 winters old, the body length is generally about 74 cm and the weight is generally about 7 kg.

(5) At the age of 5 winters, the body length is generally about 78 cm and the weight is generally about 7.5 kg. A few individuals can reach about 35 kg.

2. Grass carp breeding method

1. Pond conditions

(1) The suitable pond area is 5-10 mu. The pond should be far away from pollution sources, the bottom of the pond should be kept flat, the bottom should be loam (slight leakage is more suitable), the thickness of the bottom mud should be 10-20 cm, and the water depth should be about 2 meters.

(2) Each pond is equipped with a 4-inch water pump and a 3-kilowatt impeller-type aerator to facilitate timely water changes and oxygenation.

2. Cleaning and disinfection

(1) Drain the water in the pond, leaving a 5-10 cm layer of water, then use quicklime to make a slurry and sprinkle it all over the pond. The amount of quicklime used per mu is 100 kg. Or add 10 kg of bleaching powder into warm water and sprinkle it all over the pond after it dissolves.

(2) When spraying, make sure there are no dead surfaces or corners left, so that the germs can be completely eliminated.

3. Water quality requirements

The optimum pH value of the pond water is 7.5-8.5. From June to September, the water transparency should be kept at about 30 cm.

4. Choose seedlings

(1) The fry that swim quickly and have uniform size and body color should be cultivated. The body color of the fry should be dark grass green. The fry with black body color should be eliminated in time.

(2) Observe the swimming status of the fry in the seedling pond. If you see some fry swimming alone, crawling to the edge, or bursting out of the group when eating, it may be a precursor to the outbreak of disease.

5. Water quality management

(1) Regular disinfection

Sprinkle quicklime once every half a month, using 40 kilograms per acre of pond and per meter of water depth. You can also sprinkle bleaching powder (1PPM) throughout the pond.

(2) Water injection and water replacement

New water is added every 10 days, with each injection volume of 20-30 cm. After mid-July, the water is changed once according to the actual situation in the pond, and the water change volume is half.

(3) Turn on the aerator

Grass carp is prone to floating due to lack of oxygen from June to mid-August, so the aerator can be turned on in the early morning during this period. The best time to turn it on is 3-4 hours. It can be turned on for 2-3 hours at noon on sunny days and once at midnight on cloudy days.

(4) Patrol the pond on time

Check the activity and eating conditions of grass carp on time, observe whether there are any changes in water quality, and take early prevention measures if there is any disease, and early treatment if there is any.

(5) Clear away debris

Remove the stems, leaves and other residual feed eaten by grass carp in time.

6. Prevent fish diseases

(1) During the breeding period, most of the energy should be focused on preventing and controlling fish diseases. All links must be strictly disinfected. At the same time, Chinese herbal medicines should be fed on time, or medicated baits made with immune enhancers should be fed. The feed should be mixed 2-3 times a month and fed for 2-3 days each time.

(2) The main causes of grass carp disease are water quality deterioration or aging, water pollution, feed mold, seasonal bacteria and parasite outbreaks, etc. If grass carp has gill rot, red skin, or enteritis, it can be treated with oral and external treatments. If an outbreak is expected, the corresponding drug can be injected.

7. Matching feed

(1) Formula 1

1. Bran 38%, yeast powder 2%, bean cake 10%, flour 30%, premix 2%, rice bran 8%, fish meal 10%.

2 The feed coefficient of this formula is 1.9, and feeding green fodder can make the feed coefficient reach 2.2.

(2) Formula 2

1. Rice straw 50%, bean cake 15%, rice bran 22.5%, bran 5%, salt 0.5%, fish meal 5%, bone meal 1%, vitamin additive 1%.

2 The crude protein content in this formula can reach 18.78%, and the feed coefficient can reach 2.4.

(3) Formula 3

150% rice straw, 25% rice bran, 25% bean cake, and 10 kg of flour scraps as a binder are added to every 100 kg of the mixture.

2 The crude protein content in this formula reaches 23.35%, the feed coefficient can reach 2.8, and the feeding amount is about 0.05 kg per fish.

(4) Formula 4

1Flour 30%, soybean cake powder 15%, bran 25%, rice bran 20%, fish meal 10%.

2 The feed coefficient of this formula can reach 4.8. Under the premise that the total amount of basic feed remains unchanged, 2% calcium hydrogen phosphate, 12% sweet potato powder, 0.5% salt and 2% growth hormone can be added according to actual conditions.

8. Fish at the right time

Grass carp should be caught in time after they reach the specified size, which can reduce the fish load in the pond and increase the growth rate of the fish in the later period. Generally, they can be caught once at the end of July, and can be caught in the morning when the water temperature is lower.