Skills of saving feed in cultured Pelteobagrus fulvidraco

At present, Pelteobagrus fulvidraco is widely cultivated, and it is the main species to increase the income of agriculture and fishery in many places. However, in the process of culture, because of the one-sided pursuit of yield, many farmers do not know how to save feed and constantly put too much feed and fertilizer into the culture water, which not only increases the culture cost, but also deteriorates the water quality. affect the growth of Pelteobagrus fulvidraco, resulting in low culture efficiency. How to save feed cost in production practice?

Strict cleaning pond disinfection can not only kill wild miscellaneous fish, reduce food targets, but also kill water pathogenic factors, improve water quality, and make Pelteobagrus fulvidraco have a good feeding and growing environment. There are many wild miscellaneous fish and shrimp in the pond, which compete with Pelteobagrus fulvidraco for bait, and ferocious fish may even eat Pelteobagrus fulvidraco to reduce the feed utilization rate, so we should pay attention to its removal.

Both new and old ponds must be cleaned and sterilized before releasing seedlings. The old pond should remove too much silt and keep only 10 centimeters of sediment. The pond cleaning and disinfection was carried out 10 ~ 15 days before stocking to kill pathogens and enemy organisms in the aquaculture water. Generally, two methods can be used to clean the pond by dry method or with water. When clearing the pond by dry method, you can use about 75 kg of quicklime per mu or 4 kg ~ 5 kg of bleaching powder; when clearing the pond with water, you can sprinkle about 150 kg of quicklime per mu, so that the soil at the bottom of the pond can be mixed well with quicklime as far as possible, so as to thoroughly kill parasites, pathogens and wild miscellaneous fish, reduce the object of contention for food, and improve the utilization rate of feed. Pond culture of Pelteobagrus fulvidraco requires deep water body, sufficient water source, good water quality and energy drainage and irrigation, so it is appropriate to choose a pond with an area of 2 mu ~ 5 mu and a stable and sufficient pollution-free water source, and the water quality must meet the standard of culture water. The pond is easy to enter and drain, and the bottom is flat, which can guarantee the water depth of 1.5 meters ~ 2 meters. Because the water depth is not enough and the light is too strong, it is not suitable for the feeding habit of Pelteobagrus fulvidraco under weak light. Fish species should apply sufficient basic fertilizer before stocking, generally apply fermented organic manure to improve water quality, the dosage is 150 kg ~ 200 kg per mu, and release fish species after a large number of zooplankton appear in the pond water.

Pay attention to reasonable stocking density, can improve feed utilization rate; appropriate matching of varieties, can make full use of feed, mutually beneficial symbiosis, achieve harmony in the water body, and improve feed use efficiency. In order to improve the survival rate of Pelteobagrus fulvidraco culture and reduce the waste of feed, the stocking density and fish culture must be well controlled. When the fish species are put in, about 30 grams per fish should be selected for adult fish breeding. The stocking quantity of fish species can be flexibly controlled according to pond conditions, management level, feed supply and fish species specifications, the stocking density is appropriate, the utilization rate of too thin fishing pond is not high, the benefit is low, the fish grows slowly and induces diseases if it is too dense, and the collocation is reasonable on the premise of making full use of the water layer space of the fishing pond and not competing for food with each other. Generally, about 1500 fish can be put in 30g / tail per mu, and about 50g / tail in silver carp. The fish species should be neat in specification, bright in color, smooth in body surface, disease-free and injury-free, fin-free and physically strong, and should be washed with 5% salt water for 10 minutes before entering the pond. The species of Pelteobagrus fulvidraco are generally released in late April every year, and the matching silver carp should be released half a month after the fish has entered the pond to facilitate the growth of Pelteobagrus fulvidraco. In addition, with the continuous growth of fish body, in order to adjust the breeding density and improve the efficiency, it can be caught in batches and released in rotation, so as to adjust the fish carrying capacity in the water body and improve the feed return rate.

The amount of scientific fertilizer, bait and other culture inputs not only affects the growth of Pelteobagrus fulvidraco, but also affects the change of water quality. The food of Pelteobagrus fulvidraco in natural waters is mainly shrimp, fish and fish eggs and some aquatic insects, aquatic plants, etc., so artificial culture can use fresh animal bait, such as small fish and shrimp, livestock and poultry processing leftovers, and can also feed bean cake, peanut cake, wheat bran and so on. Generally speaking, self-made compound bait is used for domestication and feeding, and the bait is made of imported fish meal, meat and bone meal, blood meal, soybean meal, rapeseed meal, dried fish and insect and feed additives. The protein content in the early stage is more than 35% and 45%. The crude fat content is 5% to 8%; in the later stage, small miscellaneous fish meal can be used to replace part of the imported fish meal, the protein content is 30%, and the fat is about 6%. The reference formula is: fish meal 25%, bean cake 20%, vegetable cake 30%, wheat meal 20%, corn meal 3%, minerals 2%, vitamins 0.2%. The bait must be fresh, mildew-free and corruption-free, and it is appropriate to choose full-price compound feed produced by regular manufacturers. In feeding, we should pay attention to the principle of "domestication, eating early, eating less and eating more". Wild Pelteobagrus fulvidraco likes to eat during the day and night, and it can be fed on the bait table during the day after domestication for 5 ~ 7 days under the condition of artificial culture. Two days after the seedlings entered the pond, the seedlings were domesticated by artificial feeding, and the fixed feeding signal was used to carry out fixed-point and regular feeding training. It can be normal after patient domestication for 5 ~ 7 days, and the domesticated seedlings can be fed normally on the second day after entering the pond, and the feeding method can be in the form of manual and mechanical feeding. When feeding, you should start eating early and eat less and eat more. The whole feeding process should be divided into three stages. In the first stage, the bait was given four times a day in May and June, with a daily feeding rate of 3%-5%; in the second stage, three times a day from July to September, with a feeding rate of 2%-3%; and in the third stage, two times a day after October, with a feeding rate of 2%. Feed at a time when dissolved oxygen is relatively high every day. On this basis, the feeding amount should be adjusted according to the weather and water quality. In addition, due to the large mouth crack of Pelteobagrus fulvidraco, the feed size should be increased correspondingly. With the particle size of 2 mm as the open feed, the particle size of adult fish can reach more than 5 mm. The use of sinking hard pellet feed requires that the particles should be stable in water for 15 minutes, and the use of floating bait will improve the feed utilization rate.

The water quality is adjusted regularly before fish culture, and the water quality affects the growth speed and feed coefficient of Pelteobagrus fulvidraco. Pelteobagrus fulvidraco likes fresh water quality, good water quality, rapid growth and less disease, so it can make full use of bait and reduce feed coefficient. In the adult culture of Pelteobagrus fulvidraco, water quality management is the most important, and it is necessary to maintain a fresh water environment. In order to prevent the aging of the water body, the water is injected once a month in May and June, with 30 cm of fresh water each time, and once every semimonthly from June to September, about 15 cm each time, keeping the water depth at 1.2 m ~ 1.5 m. Insist on regular disinfection and sprinkle 15ppm quicklime once a month from June to September in order to purify and disinfect the water and reduce excessive organic suspended matter in the water. Use 5kg quicklime (or 2kg bleach) locally in the food farm and aerator every semimonthly. Persist in observing the algal phase and algal concentration of the water body, adjust the water fertility with inorganic fertilizers (urea, calcium superphosphate, potassium dihydrogen phosphate, etc.) according to the water color, and keep the transparency at 30 cm ~ 35 cm. According to the determination of dissolved oxygen and the weather and water quality, the aerator should be used scientifically, the machine should be turned on in the early morning and afternoon in sunny days, and mechanical oxygen should be made full use of in rainy and muggy weather to supplement the lack of dissolved oxygen in water. Dissolved oxygen should be kept above 3 mg / L.