CATDOLL : CATDOLL: Freshwater cod farming technology, what is the suitable temperature

Freshwater cod breeding technology, what is the suitable temperature

1. Pond treatment: 15 days before stocking, pour new water into the pond, and then use 80-100kg of quicklime per mu to sprinkle the whole pond. 2. Stocking density: From spring to summer, stock 150,000 to 200,000 spring fingerlings per mu, from summer to autumn, stock 15,000 to 30,000 fingerlings per mu, and raise 200-300 silver carp at the same time, from autumn to commercial fish, stock 1,800 to 2,300 autumn fingerlings per mu, and raise silver carp and bighead carp at the same time.

1. Freshwater cod breeding technology

1. Pond

(1) Before stocking, drain the water from the pond and expose it to the sun for 2-3 days.

(1) About 15 days before stocking, fill the pond with new water to a depth of 0.3m, and then sprinkle 80-100kg of quicklime per mu of pond, or sprinkle 15-18kg of bleaching powder slurry per mu of pond.

(2) About 2-3 days after disinfection, apply 200-300 kg of decomposed chicken manure per acre of pond.

2. Stocking density

(1) From water flower to summer flower, 150,000 to 200,000 water flower fingerlings are stocked per acre of pond. After about 30 days of breeding, 120,000 to 160,000 summer flower fingerlings (about 3 to 4 cm) can be obtained.

(2) From summer to autumn, 15,000 to 30,000 fingerlings are stocked per mu of pond, and 200 to 300 silver carp of the same age are raised at the same time. After about 90 days of rearing, 14,000 to 28,000 autumn fish fingerlings (80 to 100 g/fingerling) can be obtained.

(3) From autumn flake fingerlings to commercial fish, 1800-2300 autumn flake fingerlings are stocked per acre of pond, and 15-20 silver carp and 10-15 bighead carp are raised at the same time.

3. Feeding

(1) From the water flower stage to the summer flower stage, the protein content of the feed is controlled at about 42%. From the summer flower stage to the autumn flake fingerling stage, the protein content of the feed is controlled at about 38%. From the autumn flake fingerling stage to the commercial fingerling stage, the protein content of the feed is controlled at about 35%.

(2) When the water temperature is around 15℃, the daily feeding amount is 0.2-0.3% of the fish body weight. When the water temperature is 16-20℃, the daily feeding amount is 0.6-1.2% of the fish body weight. When the water temperature is 21-25℃, the daily feeding amount is 1.2-3% of the fish body weight. When the water temperature is 26-30℃, the daily feeding amount is 3-6% of the fish body weight.

(3) From the water flower stage to the summer flower stage, feed 3-4 times a day, and it is best if the fish eat all the food within 50 minutes after feeding. From the summer flower stage to the autumn flake stage, feed 2-3 times a day, and it is best if the fish eat all the food within 60 minutes after feeding. From the autumn flake stage to the commercial fish stage, feed 2 times a day, and it is best if the fish eat all the food within 60 minutes after feeding.

(4) If feeding is done more than twice a day, the amount fed in the morning should account for about 40-45% of the daily feeding amount.

2. What is the suitable temperature for freshwater silver cod?

1. Freshwater silver cod (large scale) can survive in an environment of 1-30℃, the suitable water temperature for growth is 18-27℃, and the optimal water temperature for growth is 24-27℃.

2. When the water temperature is below 15℃, freshwater silver cod almost stop eating and gather in the deep part of the pond to hibernate (during the winter, the water temperature should be kept above 4℃).

3. Freshwater silver cod is a salt-alkali tolerant farmed fish. When the salinity in the water is lower than 3.2‰ and the alkalinity is lower than 14.32mmol/L, the embryonic development of freshwater silver cod is not affected. When the salinity in the water is lower than 5.1% and the alkalinity is lower than 14.32mmol/L, the fry of freshwater silver cod are not affected.

4. During breeding, it is recommended that the salinity of the breeding water should not exceed 6‰ and the alkalinity should not exceed 25.1mmol/L.

How much temperature should cod be stored at? Should cod be frozen or refrigerated?

Cod is a kind of marine fish that we often eat. Cod can withstand a living environment of -1.9℃～2℃, so it is very cold-resistant. If the temperature exceeds 6℃, the cod will die of heat. Therefore, fishermen will freeze the cod immediately after catching it to avoid affecting the meat quality after the death of the cod. Therefore, the preservation of cod should also be paid attention to. So what temperature does cod need to be preserved?

How to store cod? Cod can be stored in fresh or frozen forms.

Fresh cod: Generally, a mixture of ice and water is needed, and the temperature is controlled at -5℃-0℃. This can not only keep the muscle tissue of the cod from shrinking, but also prevent the growth of bacteria, and keep the cod fresh as much as possible, and the taste will be better when cooked;

Frozen cod: Generally, the storage temperature of seafood should be controlled below -18℃. Try not to mix it with other seafood. This can effectively reduce the smell and preserve it effectively for a longer time! !

Should cod be frozen or refrigerated? If you are not going to eat cod for the time being, you must put it in the freezer of the refrigerator, not in the refrigerator. However, it is recommended that you eat cod products as soon as possible after purchasing them, and do not store them for too long, so as to avoid improper storage causing loss of nutrients or even deterioration.

If you buy cod in its entirety, you can freeze it directly or in sections. Do not freeze it for too long, as the water and nutrients will be lost. 2-3 months is the best.

If you have to refrigerate it, you can wrap it with plastic wrap or seal it in plastic and store it in the refrigerator. It usually lasts for 2-3 days without affecting the taste or spoiling. The temperature of the refrigerator should be set at 3-5 degrees Celsius.

How to clean cod: 1. Thaw the cod you bought and wash it with water.

2. Cut the fish body into even-sized pieces.

3. If the fish piece is a complete white piece, it does not contain internal organs and does not need to be processed.

4. The internal organs need to be picked out manually. Note that there is a black mucous membrane between the fish bones and the meat, which needs to be removed.

5. Clean the internal organs and black film of the cod, rinse it with clean water, and set aside.

Related News Scientists have discovered that cod's blood contains a substance called glycogenoprotein. This glycogenoprotein is a biological macromolecule, consisting of two galactose and three amino acids as a unit. Many units are linked together by chemical bonds to form a chain, which is coiled and curled in the blood to form loose coils. These coils are called random coils. Due to surface tension, it takes extremely low temperatures to freeze the surface of this random coil. But when it freezes, the irregularity of the surface will increase. Repeating this several times, the freezing point will be greatly reduced.