What are the key technical points for paddlefish farming?

With the continuous development and growth of our country's aquaculture industry, various types of aquaculture are constantly emerging. Among them, fish farming is still common, but there are many species of fish, so the input costs and profit returns of farming different fish are all different, and the food and growing environment required by different fish are also different.

Site selection and cage setup for paddlefish1. Selection of farming site. The farming site was selected at Chengqian Wadao Reservoir. The farming area has a large water area, a water depth of more than 6m, dissolved oxygen of 6~9mg/L, pH of 7~8.4, total hardness of 20~40mg/L, ammonia nitrogen of 0.02~0.06mg/L, and nitrite of 0.0015~0.01mg/L. The water quality is good and meets all the requirements of GB1160 "Water Quality Standard for Fisheries" and NY5051-2001 "Water Quality for Freshwater Aquaculture Water of Pollution-Free Food".2. Cage structure and setup. For cage setup, refer to silver carp cages, and choose waters with abundant plankton biomass. The requirements are stable water flow, shelter from wind and sun, and a quiet environment. The cage frame uses a simple bamboo frame. The cage body material uses polyethylene knotless netting. The cage specifications are 5m×5m×2.5m, and the mesh size is 2.5cm. Paddlefish are afraid of light, so the cage surface is covered with black film.

Main technical measures for farming paddlefish1. Seedling selection and stocking. Choose high-quality seedlings that are strong in constitution, lively in swimming, uniform in size, and free of disease and injury. The stocking density is 20~40 fish per square meter. The size is 10~15cm. According to the characteristic that paddlefish seedlings are relatively sensitive to water temperature changes, the temperature difference should not be too large when the seedlings enter the cage, and it is best not to exceed ±2℃. Try to adjust them to be consistent. Before entering the cage, disinfect the fish body with 1.5%~2.0% salt water for 8~10 minutes.2. Scientific feeding. In the early stage of stocking, feed mainly on zooplankton (such as bloodworms), then gradually domesticate them to switch food and feed floating pellet feed, supplemented by nighttime light bait. The feed is required to be fresh and not spoiled, nutritious, and suitable in particle size. Feeding follows the “four fixed” principle. When the water temperature is 20~30℃, the daily feeding rate is 1.5%~3%; when the water temperature is below 20℃, the daily feeding rate is 0.5%~1.0%. The specifics should be adjusted promptly according to feeding conditions, weather, water quality, etc. The feeding frequency is 3 times a day, respectively at 07:00~08:00, 11:00~12:00, and 18:00~19:00.3. Timely cage sorting. Paddlefish grow very fast, so they should be cultivated by size in a timely manner to avoid polarization, which is conducive to increasing the survival rate.

Management of frequent cage inspections1. Strictly implement the morning, noon, and evening cage inspection system, carefully observe the feeding and activity of the sturgeon, and promptly remove residual bait. Regularly rinse the cage to prevent mesh blockage from affecting water exchange inside and outside the cage.2. Ensure cage safety. On rainy days and in stormy seasons, pay attention to reinforcing the cage at any time. Also frequently check whether the cage is damaged, and repair it promptly if damage is found. A black light-shading nylon cloth and anti-theft net should also be installed at the upper opening of the cage.3. Keep daily records. Record air temperature, water temperature, feeding amount, and the number of diseased and dead fish every day. If abnormal conditions are found, take measures promptly.

Prevention and treatment of paddlefish diseasesAdhere to the principle of “prevention first, health management.” During seedling stocking and each cage sorting, use 1%~2% salt or 0.4mg/L dibromohydantoin and other drugs for medicinal bathing before entering the cage, and about every 20 days splash 15mg/L quicklime and 0.3mg/L dibromohydantoin inside the cage for disinfection. The use of prohibited drugs is strictly forbidden in the waters around the cage.

Farming paddlefish on the market also requires many techniques, such as the selection of its site and cage setup. These are all very important for farming. Only by choosing the correct site can there be a suitable growing environment for the fish, and only by choosing cages reasonably can the growth of the fish be better managed.