Simple Artificial Breeding Techniques of Chinese Tallow Breeds

Umbellaria is a valuable freshwater fish with high economic value and nutritional value, and it is deeply loved by consumers. In recent years, aquaculture has been promoted rapidly in Wuyi, and seedling cultivation has attracted more and more attention. Now, the breeding techniques for seedlings of Wujing are briefly introduced and only for farmers:
First, the selection and cultivation of broodstock The bream bream is best collected in September of that year. It can also be arranged for selection at the end of March and early April. To select wild or cultivated black buckwheat above the age of two winters, the specification is 0.75-1.25 kg. The requirements are disease-free, injury-free and healthy. Put it in a special pond and raise it for 1 pair every 10 square meters. Before stocking broodstock, clean up and sterilize the cultivating pool and sterilize the fish body. The ratio of male to female is 1:1.
After the spring begins, the temperature of the water gradually rises to about 15°C, and a small amount of feeding is started. The amount of feeding should be controlled at about 1% to 2% of the fish's body weight and gradually increase. When the climate and feeding are normal, the broodstock will enter the intensive cultivation period. In order to promote gonad development, flushing water should be stimulated on a regular basis on the basis of feeding 6-8% of broodstock on a daily basis. In general, in May, when the water temperature rises above 20°C, it can start production.
Second, the artificial bream oxytocin artificial oxytocin production in general from May to June, the female must choose to abdomen enlargement and loose, the outline of the ovary is obvious, the central groove appears, genital hole outburst. Males should choose body color purple red, and dorsal fins have neat and transparent white round spots arranged from bottom to top. The more white, the better.
A one-time thoracic injection method is commonly used to administer labor. The dose is: female DOM6mg + LRH-A15mg/kg body weight, and the male fish is halved. Spawning can be performed in hatching tanks, concrete fields, and earthen ponds. Hatching cylinders have the best spawning effect. After cleaning and disinfecting the incubator, inject new water and disinfect the body with 1ppm malachite green, and then put a suitable amount of water peanuts into the fish nest. After the broodstock has been injected with hormones, it is placed in the incubator tank in the form of “pair” and the hatching cylinder is covered with a fish net to prevent it from jumping out. The use of waterstop or microfluidic water can be used. The effect time is shortened as the water temperature rises, generally 27-35h when the water temperature is 22-23°C, and 24-30h when 24-25°C. The spawning of blackbirds takes place under quiet and low light and cannot be frightened, otherwise it will stop spawning. Generally, eggs are collected from the first 12 to 14th day after spawning. The eggs should be collected with water, and the unfertilized fish eggs (white eggs) are removed and placed in the incubator according to a certain amount for hatching.
Third, artificial hatching fish eggs hatching cage can be used (40cmX100cmX50cm) microfluidic method, each box put 10,000 fertilized eggs; hatching pool hatch (3mX4mX0.8m), each pool put 4 to 50,000 fertilized eggs. The level of hatching rate depends on the fertilization rate of fish eggs and the freshness of water quality. Therefore, it should be done to: prevent the occurrence of water mold disease; keep the water quality fresh; operate lightly to prevent damaging fish eggs; and prevent sudden water temperature changes.
Fourth, the seedling cultivation of Chinese wolfberry oxytocin hatching is easy, the fry cultivation is difficult, the workload is large and detailed, the survival rate is low, a little negligence, and the previous work is abandoned.
1. After 4-5 days of larval domestication, the larvae are fed with larvae of the zooplankton and individuals are controlled below 200μm. The method of small meals is used, usually 4h, after 3-4 days, the quantity gradually increases, and the number of feedings gradually increases. Decrease, transition to feeding twice a day is appropriate. After 1 to 7 days from the membrane, there is a serious phenomenon of colony inhabitation and the phenomenon of “red worms”. Therefore, in the event of clustering, the practice of agitating the water in a timely manner can improve the survival rate of the seedlings. Remove unfertilized eggs and residual egg membranes in time, remove bottom dirt, and change water once a day. Pay attention to control aquatic fungus and parasites of protozoa. When the fry is domesticated for 5-6 days (ie, the 9-10th day after filming) when the fry grows to 1 to 1.4 cm, its respiratory system is more complete and its activity is enhanced, which means it can normally feed. As the individual grows up, it is necessary to carry out rearing, pooling, and lowering the density to enter the summer flower species breeding.
Second, the cultivation of summer fish species Summer cultivation can be carried out using cement pools. The concrete pool is generally chosen to have a rectangle of 4mX3mX0.8m, and is provided with an intake and drainage system, an aeration equipment, a row seedling and a food table. Above the cultivation pool, the best is to have a plastic greenhouse, which can prevent direct sunlight and heavy rain, ensure the relative stability of the environment, and facilitate management, operation, disease prevention and treatment. Stocking densities: Generally, 400-500 tails/square meter will be cultivated in the pond; micro-fluid culture may be stocked at 600-800 tails/square meter, or even 1000 tails/square meter. In the newly hatched fry, fresh zooplankton is still used as feed. When the fry grows to more than 2cm, dead and zooplankton can be bagged in addition to fresh live zooplankton every day. If demand exceeds supply, yeast protein, fishmeal (meatball), wheat flour, etc. can be mixed in the stagnant water. Do small meals, let the fry eat, improve the survival rate. To strengthen the water quality regulation, pay attention to fish pond fish and increase oxygen regularly.
When the fry grows to 3~4cm, it can be moved into a large pool or cage to cultivate fish species.