Practical Tips for Saving Feed in Yellow Catfish Farming

Currently, yellow catfish (Pelteobagrus fulvidraco) farming is quite widespread and is a major species for increasing income among fish farmers in many places. However, during the farming process, many farmers, in their one-sided pursuit of output, do not know how to save feed and continuously put excessive feed and fertilizer into the aquaculture water. This not only causes farming costs to rise day by day, but also continuously deteriorates water quality, affecting the growth of yellow catfish and resulting in low farming benefits. How can feed costs be saved in production practice?

Strictly remove trash fish and disinfect the pond. Pond disinfection can both kill wild trash fish and reduce competitors for food, and kill pathogenic factors in the water body, improving water quality and giving yellow catfish a good feeding and growth environment. If there are many wild trash fish and miscellaneous shrimp in the pond, they will compete with yellow catfish for bait, and ferocious fish may even prey on yellow catfish, reducing feed utilization rate, so attention should be paid to removing them.

Before stocking fry, both new and old ponds must be cleaned and disinfected. Old ponds should have excess mud removed, retaining only 10 cm of bottom mud. 10 to 15 days before stocking @#@233@#@, disinfect the pond with chemicals to kill pathogens and harmful organisms in the aquaculture water. Generally, two methods can be used: dry pond disinfection or disinfection with water. For dry pond disinfection, about 75 kg of quicklime per mu or 4 kg to 5 kg of bleaching powder can be used; for disinfection with water, about 150 kg of quicklime per mu can be spread over the whole pond, and the bottom soil should be mixed with quicklime as much as possible to thoroughly kill parasites, pathogens and wild trash fish, reduce food competitors and improve feed utilization rate. Pond farming of yellow catfish requires relatively deep water, abundant water sources, good water quality, and drainage and irrigation capability, so ponds of 2 mu to 5 mu should be chosen, with a stable and sufficient unpolluted water source, and the water quality must meet aquaculture water standards. The pond should have convenient inlet and drainage, and a flat bottom, and be able to guarantee a water depth of 1.5 m to 2 m, because insufficient water depth and overly strong light are not suitable for the yellow catfish's habit of feeding under weak light. Before stocking fingerlings, sufficient base fertilizer should be applied. Generally, fermented organic manure is used to fertilize the water, at 150 kg to 200 kg per mu. After large numbers of zooplankton appear in the pond water, the fingerlings are stocked.

Pay attention to rational stocking. A reasonable stocking density can improve feed utilization rate; suitable species combination can make full use of feed, achieve mutual benefit and symbiosis, achieve harmony in the water body, and improve feed use efficiency. To achieve a high survival rate in yellow catfish farming and reduce feed waste, stocking density and companion fish species must be well controlled. When stocking fingerlings, large-sized fingerlings of about 30 g each should be selected for grow-out culture. The stocking quantity of fingerlings can be flexibly controlled according to pond conditions, management level, feed supply and fingerling size. The stocking density should be as appropriate as possible; too sparse means low pond utilization and low benefits, while too dense means slow fish growth and induced disease. The combination should be reasonable, with the premise of fully utilizing the pond's water layers and not competing for food. Generally, about 1,500 yellow catfish fingerlings of 30 g each can be stocked per mu, and about 200 silver carp and bighead carp of 50 g each can be stocked in combination. The stocked fingerlings should be uniform in size, bright in color, smooth in body surface, free of disease and injury, with complete fins, and robust in physique. Before entering the pond, they should be soaked in 5% salt water for 10 minutes. Yellow catfish fingerlings are generally stocked in late April each year, and the companion silver carp and bighead carp should be stocked half a month after the yellow catfish enter the pond, to benefit the growth of yellow catfish. In addition, as the fish continue to grow, in order to regulate stocking density and improve benefits, they can be harvested in batches for market and subjected to rotational harvesting and stocking, to regulate the fish carrying capacity in the water body and improve feed return rate.

Scientific fertilization and feeding. The amount of farming inputs such as fertilizer and bait affects both the growth of yellow catfish and changes in water quality. In natural waters, the food of yellow catfish is mainly small shrimp, fish and fish eggs, and some aquatic insects and aquatic plants. Therefore, artificial farming can use fresh live animal bait such as small fish and shrimp, and scraps from livestock and poultry processing, and can also feed soybean cake, peanut cake, bran, etc. Generally, self-made compound bait is mostly used for domestication feeding. The bait is made by combining imported fish meal, meat and bone meal, blood meal, soybean meal, rapeseed meal, dried fish worms, etc. with feed additives. In the early stage, the protein content is above 35% to 45%, and the crude fat content is 5% to 8%; in the later stage, small trash fish meal can replace part of the imported fish meal, and a protein content of 30% and fat of about 6% is sufficient. The reference formula is: fish meal 25%, soybean cake 20%, rapeseed cake 30%, @#@245@#@ meal 20%, corn meal 3%, minerals 2%, vitamins 0.2%. The bait fed must be fresh, free of mold and spoilage, and full-price compound feed produced by regular manufacturers should be chosen. During feeding, attention should be paid to grasping the principles of "domestication feeding, early feeding, and small meals more often." Wild yellow catfish like to feed at night and hide during the day. Under artificial farming conditions, after 5 to 7 days of domestication, they can completely come to the feeding table to feed during the day. Two days after the fry are stocked, artificial feeding domestication is adopted. During domestication, a fixed feeding signal is used to train them to feed at a fixed point and fixed time. After patient domestication for 5 to 7 days, they can feed normally; for domesticated fry stocked in this way, normal feeding can begin on the second day after entering the pond. Feeding can be carried out in two forms: manual and mechanical. When feeding, early feeding and small meals more often should be achieved. The entire feeding process should be divided into three stages. In the first stage, in May and June, feed 4 times a day, with a daily feeding rate of 3% to 5%; in the second stage, from July to September, feed 3 times a day, with a feeding rate of 2% to 3%; in the third stage, after October, feed 2 times a day, with a feeding rate of 2%, feeding during the period each day when dissolved oxygen is relatively high. On this basis, the feeding amount should also be adjusted according to weather and water quality conditions. In addition, because yellow catfish have a relatively large mouth opening, the bait particle size should be correspondingly increased. Pellet feed with a particle size of 2 mm is used as the opening feed, and the particle size of adult fish feed can reach more than 5 mm. Sinking hard pellet bait is required to remain stable in water for 15 minutes, and using floating bait will better improve bait utilization rate.

Regularly regulate water quality. To farm fish, first cultivate water. The quality of water affects the speed of yellow catfish growth and the feed coefficient. Yellow catfish like fresh water quality. With good water quality, they grow quickly, have fewer diseases, can fully utilize bait, and reduce the feed coefficient. In grow-out farming of yellow catfish, water quality management is the most critical, and a clean water environment needs to be maintained. To prevent water aging, in May and June, add water once a month, exchanging 30 cm of new water each time; from June to September, exchange water once every half month, exchanging about 15 cm each time, maintaining a water depth of 1.2 m to 1.5 m. Persist in regular disinfection. From June to September, use 15 ppm quicklime to spread over the whole pond once a month, to purify and disinfect water quality and reduce excessive organic suspended matter in the water. Every half month, use 5 kg of quicklime (or 2 kg of bleaching powder) for local treatment once at the feeding ground and aerator area. Persist in observing the algal phase and algal concentration in the water body, and according to water color use inorganic fertilizer (urea, superphosphate, potassium dihydrogen phosphate, etc.) to regulate water fertility, maintaining transparency at 30 cm to 35 cm. According to dissolved oxygen measurements and weather and water quality conditions, scientifically use aerators. On sunny days, persist in running them for 1 hour in the early morning and afternoon. In rainy, cloudy and muggy weather, make full use of mechanical aeration to supplement insufficient dissolved oxygen in the water body. Dissolved oxygen should be maintained above 3 mg/L.