The colony biology carp, also known as the Chinese silver carp, is capable of breeding in our country. In the northern regions, its spawning season typically occurs between September and November, while in the southern areas, it takes place from November to January. These fish reach sexual maturity at the age of 3 to 4 years. Female carp can produce approximately 100,000 eggs per kilogram of body weight. The eggs are released in batches, with each batch containing mature eggs that have a single oil globule, making them buoyant. The size of the eggs ranges from 1.22 mm to 4.5 mm, with some reaching up to 1.50 mm. Fertilized eggs are incubated at water temperatures between 16°C and 19°C, and they typically hatch after 3 to 4 days of incubation. Newly hatched larvae measure about 4.42 mm to 4.6 mm in total length. By the fourth day after hatching, the yolk sac is nearly depleted, and the mouth opening reaches approximately 0.75 mm to 0.80 mm, marking the start of feeding.
There are two primary sources for broodstock: wild-caught adults from the sea or selected breeding groups. The most effective method for capturing broodstock is using fixed nets, which minimize injury and improve survival rates. Broodstock are transported in water tanks within vehicles and then kept in pools with oxygen supply. For injured individuals, surface disinfection with potassium permanganate or malachite green is recommended, and in severe cases, gentamicin injections may be administered to aid recovery.
Oxygen production, fertilization, and broodstock rearing are all carried out under controlled environmental conditions, with artificial oxytocins such as gonadotropin-releasing hormone analogues (LRH-A) and human chorionic gonadotropin (HCG) used to induce spawning. These agents can be used alone or in combination, depending on the maturity level of the broodstock. Spawning in wild populations varies significantly, and mature broodstock usually begin ovulating 24 to 36 hours after injection. When the eggs are ready, either dry or wet fertilization is performed in a box, with seawater gently stirred for 5 minutes to ensure even mixing and high fertility rates.
For incubation, fertilized eggs are placed in conical cages or egg boxes with a diameter of 80 cm and a height of 60 cm, while the cone itself is 40 cm tall. The egg density ranges from 1.1 million to 500,000 eggs per cubic meter. Bottom air stones are used to provide continuous aeration, ensuring the water moves slowly and uniformly. It's best to use filtered water through sedimentation. Water should be changed 2–3 times daily, with a full water exchange each time. The walls of the containers should be washed every 2 hours to prevent embryos from sticking and to remove any dead eggs promptly. Incubation duration depends on water temperature, with hatching occurring after about 3–5 days. Maintaining clean water and sufficient dissolved oxygen ensures a hatching rate of over 80%.
Larval rearing can be conducted indoors in controlled environments or outdoors in earth ponds. Indoor breeding uses static water with micro-aeration and regular water changes, gradually transitioning to a constant flow system. Larvae are stocked at a density of 0.5–1.0 thousand per cubic meter. Feeding includes rotifers, Artemia, copepods, and other suitable food sources. Outdoor pond cultivation can also utilize ecological fertilizers to support natural food production.
Emulsifier And Dispersant, Biodegradable Compound Emulsifier,Chemical Compound Emulsifier
Henan chinamian foods CO.LTD , https://www.ooossooo.com