What are the breeding methods and precautions for the iridescent shark?
The iridescent shark, also known as the axe shark, is a fish favored by anglers in Southeast Asian countries. It is mainly distributed in rivers and other water bodies in mountainous areas, and is a small wild economic fish valued for its flesh. Many people like to keep it as an ornamental fish, so how do you raise an iridescent shark?
1. Pond conditions: For monoculture of the iridescent shark, the pond area should preferably be 2000-3000 sq m, with a water storage depth of about 1.5-2 m, at 2000-3000 fish per mu. For polyculture of the iridescent shark, the pond density should preferably be 100 fish per mu.
2. Water temperature control: The iridescent shark inhabits the middle and lower layers of the water body. Its suitable growth temperature is 22-26°C. When the water temperature drops to 14-18°C, its activity decreases, and at 12-13°C it will go into shock and die, so a cold-proof shed is generally built during breeding.
3. Stocking density: The stocking density of the iridescent shark should be determined according to actual conditions. Usually, for monoculture, 2000-3000 fish of about 3-4 cm are stocked per mu. When mixed with silver carp, grass carp and tilapia, it is 100 fish per mu.
4. Feed selection: The iridescent shark has low feed requirements, and a crude protein content above 27% is sufficient. Depending on local conditions, water hyacinth or water spinach can be beaten into a pulp and mixed with crushed corn and soybean residue for feeding.
5. Feed feeding: The feed for the iridescent shark should be given at fixed times, in fixed locations, with fixed quality and in fixed amounts, and the protein content of the compound feed should be greater than 40%.
6. Water quality management: During the feeding process, pay attention to changes in water quality, change the water frequently, feed less but more often, to ensure the healthy growth of the fry.
7. Disease prevention and control:
(1) Fin rot disease: The symptoms are congestion and ulceration of the tail fin and dorsal fin of the fish. Sick fish do not eat and die in large numbers. The cause is bacterial infection, and it is a serious infectious disease at the fry and fingerling stage. Pond water can be disinfected with 15 mg/L formalin or 10 mg/L potassium permanganate or 10-20 mg/L bleaching powder solution. Antibacterial drugs can also be added to the mixed feed. For every thousand fish fingerlings, use 30-40 tablets of oxytetracycline per day for 7 consecutive days, and the sick fish can be cured.
(2) White spot disease: Also known as ichthyophthiriasis, this disease is prone to occur when the water temperature is 20-24°C. The symptoms are white spots on the body surface, and in severe cases pus blisters form, and the fish body becomes thin and separates from the group. The whole pond can be splashed with 0.1-0.15 mg/L mercurous nitrate, and repeated once after 3-4 days, and the ichthyophthirius will fall off automatically.
Overall, the iridescent shark is still quite easy to raise. As long as the pond is built well, the density is controlled well, the feed is good, and disease prevention and control are done well, it will be fine.