Pond Stocking Methods and Technical Key Points for Yellow Catfish
Yellow catfish (scientific name: Pelteobagrus fulvidraco), a fish of the family Bagridae, genus Pelteobagrus. Body length about 20cm, ventral surface flat and straight, posterior half of body laterally compressed, caudal peduncle relatively slender. Head large and flat, snout short, rounded and blunt, upper and lower jaws slightly equal in length, mouth large, inferior, with villiform tooth bands on both cheeks and palatine bones. Eyes small, lateral. Four pairs of barbels; the nasal barbels can extend to behind the eyes, one pair of maxillary barbels, the longest, and two pairs of mental barbels, shorter than the maxillary barbels. Body naked without scales, lateral line complete. Omnivorous, mainly feeding on benthic small animals, small shrimp, small aquatic insects and some invertebrates. Spawns in April-May; parent fish have the habit of digging pits and building nests and protecting their offspring. During the reproductive period, male fish have the habit of building nests. Inhabits still water or slow-flowing shallows, hiding by day and coming out at night. Widely distributed in the Pacific river systems of eastern China.
How to use ponds to stock yellow catfish?
1. Water body conditions:
Yellow catfish prefers to inhabit still water or slow-flowing water. Its survival temperature range is wide, generally 0°C-39°C, the most suitable growth water temperature is 22°C-28°C, the most suitable pH range for the water body is 7.0-8.5, and the suitable dissolved oxygen level is above 3.0 mg/L.
2. Pond conditions:
Ponds with sufficient water source, good water quality, convenient water inlet and drainage, flat pond bottom, less silt, and no seepage or leakage can all be used for farming. The area is preferably 3-5 mu, with a water depth of about 1.5 m. Install inlet and drainage screens and protective nets to prevent fish fry from escaping when the water rises. Large ponds need to be equipped with aerators. 10-15 days before releasing the fingerlings, apply 75-100 kg of quicklime or 10-15 kg of bleaching powder per mu, dissolved into a slurry and splashed over the whole pond, to kill wild miscellaneous fish and pathogenic organisms in the pond. 5-7 days after pond clearing and disinfection, add about 1 m of fresh water to reduce ammonia, nitrogen and nitrite.
3. Fingerling stocking:
Generally, about 40,000-60,000 yellow catfish of 6-8cm per fish are stocked per mu of water surface, and the fingerling size should be uniform. To prevent fish diseases, the fingerlings must be soaked in medication during stocking, generally soaked in 10 ppm potassium permanganate or a 2% to 4% salt solution for 5 to 10 minutes.
4. Feed feeding:
Yellow catfish is a carnivorous-based omnivorous fish, fond of “live, fishy, soft” feed. Small fish, small shrimp, snail and mussel meat, offal from livestock and poultry processing plants and other animal bait can be minced, then mixed thoroughly into balls using native flour (middlings) as a binder, and placed on a feeding platform for feeding. Artificial compound pellet feed can also be fed. The reference formula is: fish meal 30%, soybean cake 30%, wheat bran 20%, corn 10%, native flour (middlings) 16%, meat and bone meal 1%, mineral additive 1%, multivitamin 1%, fish oil 1%. Special feed for yellow catfish or general fish feed containing more than 40% protein can also be used. Feeding should be done at fixed times, fixed locations, fixed quality and fixed quantity. The daily feeding amount accounts for 2%-8% of fish body weight, and should be flexibly controlled according to water temperature, weather and the fish's feeding situation. Generally, feed once each day at 9-10 a.m. and 4-6 p.m. Because yellow catfish prefers to feed under low light, feed 1/3 of the daily feeding amount in the morning and 2/3 in the afternoon. When standard-sized fry are first put into a large pond, because the fry are relatively small, try to feed them powdered feed; after they are slightly larger, pellet feed can be fed. Floating feed is now commonly used, so it can be seen whether the fish have eaten their fill; once the fish stop eating the feed, feeding can be stopped.
5. Rearing management:
Yellow catfish is a bottom-dwelling fish, fond of high dissolved oxygen and fresh water quality. Paying attention to water quality regulation can promote its growth and improve feed utilization. Generally, in May-June, add fresh water once every 10-15 days; in July-September, add fresh water once every 7-10 days, adding 10-15 cm each time. If the water is too fertile, first discharge part of the old water, then add fresh water, with transparency at about 35 cm. Always keep the water quality ‘fertile, lively, tender and refreshing’. In the early morning, the dissolved oxygen in the pond water is relatively low, and sometimes hypoxia occurs. At this time, yellow catfish will be seen constantly jumping out of the water. Measures should be taken immediately: inject fresh water, start the aerator, increase the oxygen content in the water, and regulate the water quality, so that the fish no longer gasp at the surface.
6. Disease prevention and control:
Yellow catfish has strong disease resistance and few diseases. As long as prevention is proper, it generally does not easily become diseased. Regularly add 1% salt to the feed and feed continuously for 5-7 days. The bait fed should be fresh and clean, and spoiled and deteriorated bait must not be fed. Every 20-30 days, splash 20 g/cubic meter of quicklime over the whole pond once. Each month, use 1-1.5 mg/cubic meter of bleaching powder or 0.3 mg/cubic meter of strong chlorine for sterilization once, and regularly kill parasites. Once disease is found, microscopic examination should be carried out promptly, and after comprehensive analysis and diagnosis, apply the appropriate medicine; and strengthen pond water renewal and disinfection measures. At the same time, try to avoid injuring the fish body during harvesting, releasing and transportation, to prevent infection with water mold disease in the low-temperature seasons of early spring and autumn and winter.