How much does a largemouth bass fry cost? Detailed guide to farming methods
The largemouth bass, also known as the bigmouth bass, originated in freshwater lakes in the Americas and inhabits waters with low turbidity and aquatic plants. It was introduced to China around the 1980s. Its flesh is delicious and its taste is excellent, and it reproduces rapidly, so many fishery farmers prefer to farm it. Let's take a look below at largemouth bass fry prices and farming methods!
How much does a largemouth bass fry cost per fish?
The price of largemouth bass fry is about 0.15 to 0.3 yuan per fish, but prices vary depending on the fry's size, quality, market and purchase quantity. The largemouth bass has the habit of guarding its eggs; after the fry hatch from the membrane and can swim horizontally, the male fish leaves the nest to forage. Newly hatched fry are nearly white and semi-transparent, with a total length of 7 to 8 mm, and swim in schools. After the yolk is absorbed on the third day after hatching, they begin to feed on small green algae and rotifers, and later feed on small cladocerans, copepods and other plankton. Fry within 1 month of hatching in natural waters still form schools and are protected by the male parent fish.
Seed breeding of largemouth bass
1. Parent fish cultivation: When harvesting adult fish, select largemouth bass with good physique, large individual size, no injuries and no diseases as reserve parent fish, and cultivate them in dedicated ponds, stocking 300 to 400 fish per mu. During cultivation, the bait is mainly small fish and small shrimp, and the daily feeding amount is about 3 to 5% of body weight.
2. Building spawning ponds: Before the breeding season arrives, prepare spawning ponds according to the scale of production. A soil pond with a sandy bottom and sloped banks is ideal, with an area of 1 to 2 mu being suitable. Pile some stones and bricks around it, and plant some aquatic plants in the pond for the parent fish to build nests before spawning.
3. Artificial induced spawning: Pair parent fish by individual size at 1:1 and inject hormones to induce spawning. Carp pituitary can be used at 5 to 6 mg per kg of female parent fish; the first injection dose is 15%, and the remainder is injected 12 to 14 hours later. Male parent fish are given a single injection of 2 mg when the female fish receives the second injection.
4. Spawning time: The induction effect time for largemouth bass is relatively long. At a water temperature of 22 to 26°C, it takes 18 to 30 hours after hormone injection for estrus and spawning to occur. It is also a multiple-spawning type; parent fish can be seen spawning continuously for 1 to 2 days in one spawning pond, and spawning is completed only on the third day.
5. Hatching methods: Largemouth bass eggs hatch in 31 to 33 hours at a water temperature of 20 to 22°C, and take 52 hours to hatch fry at a water temperature of 17 to 19°C. For artificial hatching, using a cement pond with slight flowing water or using cages for still-water hatching in a pond with fresh water quality and high dissolved oxygen is better.
Farming methods for largemouth bass
1. Pond conditions: Largemouth bass ponds require sufficient water sources, convenient drainage and irrigation, no leakage, a water depth of more than 1.5 m, good water quality, no pollution, ventilation and light transmission, and loam as the bottom soil. The area should not be too large, with 1 to 2 mu being suitable, and an aerator should be equipped.
2. Stocking density: For largemouth bass, generally 2000 to 2500 fry are stocked per mu. Ponds with good conditions and equipment can stock 3000 to 4000 fry. Properly polyculture silver carp, bighead carp, grass carp and bream to help clean up feed residues and regulate water quality.
3. Bait selection: The key to farming largemouth bass is having enough bait fish. You can use fingerling ponds to cultivate silver carp and bighead carp fry, or use adult fish ponds and use nets to enclose part of the pond body to farm small fish, and you can also buy wild miscellaneous fish or special compound bait.
4. Bait feeding: Largemouth bass is a ferocious fish that feeds on live fish. Feeding is usually divided into one feeding in the morning and one in the afternoon. At a water temperature of 20 to 25°C, the daily feeding amount is 10 to 15% of fish weight, but it should be flexibly controlled according to the fish's feeding and activity conditions and weather changes.
5. Daily management
① Pond inspection: Inspect the fish pond every day, observe fish school activity and water quality changes, avoid pond water being too turbid or too fertile, with transparency of 30 cm being suitable, and promptly discover problems and take measures to solve them.
② Drug prevention: Strictly prevent pesticides, public hazard substances and the like from flowing into the pond to avoid fish death in the pond. Young fish in particular are extremely sensitive to pesticides; even a very small dose can cause the death of all fry in the pond, so great attention must be paid.
③ Feeding: The feeding amount must be appropriate, and absolutely avoid too much or too little. At the same time, avoid long-term use of a single feed. Vitamins and minerals should be added to the feed to maintain normal nutritional requirements.
④ Grading and thinning: Grade and thin in a timely manner, about once every 2 months, and stock fish of the same size in the same pond to avoid big fish eating small fish. The separation work should be carried out on mornings with good weather, and absolutely avoid separation when the weather is hot or cold.
Disease prevention and treatment of largemouth bass
1. Trichodiniasis and Chilodonelliasis
[Symptoms] It mostly occurs in water bodies with small pond area, shallow water level, high farming density, much organic matter in the water body or water quality that is too lean; it is more likely to occur during continuous rainy weather. Microscopic examination shows a large number of parasites parasitizing on the fish body surface and gills.
[Prevention and treatment] Regularly splash Xianchongmie over the whole pond. For treatment, on the first day splash Sanxiao Digai 250 g/mu + Likejing 33 ml/mu over the whole pond, and on the second day splash Yufengdian 500 ml/mu or compound iodine 66 ml/mu over the whole pond for disinfection.
2. Lernaeosis
[Symptoms] The parasites parasitize on the base of the dorsal fin, pelvic fin and caudal fin and on the body surface. The parasite body can be seen with the naked eye partially exposed outside the host. The parasitic site generally shows bleeding, the fish body becomes thin, and appetite decreases.
[Prevention and treatment] Use Chongzaojing 25 to 35 ml per mu of water surface with a water depth of 1 m. If it recurs, use it once more to thoroughly kill the Lernaea in the water body.
3. Bass ulcer disease
[Symptoms] Diseased fish have inflammatory lesions of varying sizes on the body sides, caudal peduncle, abdomen, head and fin bases. Scales fall off at the lesions, with bleeding and inflammation, and the epidermis and dermis all rot and fall off, exposing congested muscle.
[Prevention and treatment] For external use, disinfect with chlorine preparations or splash Yujing 500 ml/mu over the whole pond for disinfection, once daily, for 2 to 3 consecutive times. At the same time, orally administer Yufukang 0.15 g + Tailiwei 0.2 g per 1 kg of fish body weight for 5 to 7 consecutive days.
4. Largemouth bass enteritis
[Symptoms] Diseased fish have a darkened body and become thin, the intestinal wall is congested and red, and in severe cases the abdomen is swollen, the anus is red and swollen and protruding, with yellow mucus flowing out. They often swim alone away from the group or rest quietly at the bottom, and appetite decreases markedly.
[Prevention and treatment] The feed fed must be fresh and high quality. Allium sativum powder or oxytetracycline can be added to the feed to make medicated bait for feeding, for 3 to 5 consecutive days.
5. Saprolegniasis
[Symptoms] The wounds on the body surface of diseased fish appear to have clusters of grayish-white flocculent material attached. The fish body is very weak and powerless, floating on the water surface. It is prevalent every winter and spring, and often occurs as a secondary infection in the lesions of ulcer disease, causing massive death.
[Prevention and treatment] Remove excess sludge at the bottom of the pond, and use 200 ppm quicklime or 20 ppm bleaching powder to clear and disinfect the pond. Splash Mumuan 100 ml/mu over the whole pond, and orally administer antibacterial drugs (such as Yufukang, sulfonamides, etc.) to prevent bacterial infection.