Tilapia is a small and medium-sized fish. Its shape and size are similar to that of squid. Its fins are like squid. The main species in China are Nile tilapia, Oreochromis, and Mozambique tilapia. Miscellaneous combinations
Tilapia culture technology
Tilapia is a small and medium-sized fish. Its shape and size are similar to that of squid. Its fins are like squid. The main species in China are Nile tilapia, Oreochromis, and Mozambique tilapia. Hybrid progeny of various combinations, etc., have a high breeding value. Let's take a look at the culture technology of tilapia!
Tilapia living habits
1, food miscellaneous: tilapia is a plant-based omnivorous fish. In tilapia in ponds Tilapia production line , the contents of the digestive tract are mostly organic debris and other plant-based feeds (such as aquatic plants, commercial feeds, etc.), followed by phytoplankton, zooplankton and a small number of benthic animals.
2, low-oxygen resistance: tilapia is very resistant to hypoxia, the suffocation point is 0.07 ~ 0.23 mg / liter, when dissolved oxygen 1.6 mg / liter in water, tilapia can still live and breed. When the dissolved oxygen in water is more than 3 mg/L, the growth is not affected.
3, not resistant to low temperature: tilapia survival temperature range of 15 ~ 35 ° C. When the water temperature is below 15 °C, the tilapia is dormant. The highest critical temperature of tilapia is about 40 ~ 41 ° C, the most suitable growth temperature is 28 ~ 32 ° C, tilapia breeding temperature is above 20 ° C.
4, strong fertility: tilapia sexual maturity early, short spawning period, oral incubation of juvenile fish, breeding conditions are not high, large water area in the static water body naturally multiplication.
The suitable water temperature for tilapia reproduction is 22 to 23 ° C, and it usually spawns naturally after mid-May. In order to grab the season and make full use of the light, heat and bait resources to increase the aquaculture production, artificial warming, intensive cultivation, and early spring propagation must be adopted to enable tilapia to lay eggs in mid-April. The specific measures are as follows.
1. Selection and cultivation of broodstock: Select the broodstock with good maturity to be placed in the spawning pool in mid-March to strengthen the breeding. The spawning pool can use the wintering pond. Generally, 6 broodstocks are stocked per square meter of spawning pool. The ratio of male to female is 2:1 or 3:1, and water should be changed regularly.
2. Temperature increase and feeding management: The water temperature in the pool should be controlled above 23 °C. The water quality requires fertilizer, live and cool. The amount of feed can be determined according to water temperature, water quality and fish growth. In general, the daily intake of the static pool is 2% of the weight of the fish, and the flow pool is 3%. At the same time, it is necessary to constantly observe the activity of the fish and the degree of gonadal development, and make various records.
3, spawning: tilapia male and female fish body color has a clear difference, estrus male fish swimming in the pool, looking for a place to do the nest. The shape of the nest is a pot shape with a diameter of 30 to 40 cm and a depth of about 10 cm. After the nest was built, the male fish seduce from the female fish from time to time and intercepted the female fish into the nest. When the water temperature reaches 22 to 23 ° C, the female can lay eggs. When spawning, the female fish's abdomen is close to the bottom of the nest, and the male fish guards the nest. After the female fish lays eggs, the eggs are immediately sucked into the mouth, and the mandibular bulge is cystic. The male fish then enters the nest and the sperm is sucked into the mouth with the water. The egg is fertilized in the mouth.
4, hatching: tilapia fertilized eggs hatch in the mouth of females, and flipping with the breathing of females, both to protect the mother, but also has a good incubation environment. When the water temperature is around 30 °C, the fry hatch in about 4 to 5 days, and it takes about 7 days at 25 °C.
Tilapia culture technology
1. Pond preparation: The area is 3-5 mu, and the bottom of the pool is flat. 10 days before stocking, 60-70 kg of raw lime per acre is sprinkled with clear pond disinfection. After 2-3 days, 75-100 kg of farmer's fertilizer, such as chicken fat and pig manure, is applied per mu, and water is injected to one meter. After the water color turns into brown or oil green, the fry can be placed.
2, fish stocking and matching: the southern region to the middle and late April, when the temperature rises stable (water temperature above 18C) when the seedlings. Each season, the size of 3.0-3.5cm of Onyxia squid is 2000-2500, 40 large-sized flower buds, 30 white peony, and a small amount of squid and squid.
3. Pre-feeding: After releasing the fish fry, stir the soaked peanut cake or rapeseed cake and evenly spread it along the pond to the center, and feed 1.5-2 kg per acre per day. After a month of breeding, the fry can grow to about 10 cm and weigh 10-12 grams.
4, middle and late management
1 Feed feeding: The growth temperature of Oreochromis is 22-32C, and the appetite is strong. Feeding is wide-ranging, so that all fish species are fed as much as possible. The feed has rapeseed cake, glutinous cake, wheat bran, peanut cake, bean cake, etc., and it is best to mix and use. Conditional feeding of tilapia full-price compound feed, feeding twice a day, 9:00-10:00 am, 4:00-5:00 pm. Daily feeding amount: body weight 10-20 grams, 5-7%, 20-50 grams, 4-6%: 50-100 grams, 3-5%, 100-200 grams, 2-4%: 200 grams or more, It is about 2% of the weight of the fish.
2 Water quality regulation: From mid-May to June, water can be gradually added to 1.5 meters. July and August are high temperature seasons. Add water to 1.8 meters. It is best to change the water once a week to keep the water fresh. To prevent pan-Tang phenomenon.
3 prevention and control of fish disease: adhere to the principle of prevention and prevention, and the fish species can be washed with 4-5% saline solution for 10-15 minutes before stocking. May-September is a season of frequent fish disease. Every half month, you can use bleaching powder 1ppm or quicklime 20kg/mu to splash the whole pool. When there are signs of fish disease, antibiotics and vitamins can be used for 3-5 days.