Cage culture technology of Pelteobagrus fulvidraco (artificial culture technology of Pelteobagrus fulvidraco)

Pelteobagrus fulvidraco, as one of the traditional famous breeds, is deeply loved by

Cage culture technology of Pelteobagrus fulvidraco (artificial culture technology of Pelteobagrus fulvidraco)

Pelteobagrus fulvidraco, as one of the traditional famous breeds, is deeply loved by consumers because of its tender meat, less thorns and high nutritional value. In recent years, with the success of artificial propagation and seedling raising, large-scale farming has developed rapidly. This paper introduces the cage culture technology in lakes.

I. Aquaculture Water Body

The water area of the cage is more than 100 mu, and the dissolved oxygen in the water body is required to be more than 4 mg/L for a long time, the transparency of the water body is 40-50 cm, and the water body is pollution-free. The size of the cage is 4m long, 3m wide and1.2m deep. Grid 5? 8 mm, polyethylene net without knots, the cage is covered with sunshade net, and there is a feeding mouth of 0.5 square meters in the middle. The upper opening of the cage is made of bamboo, holes are drilled in the bamboo every 0.5 meters, and round steel with a diameter of 8 mm is inserted to fix the upper opening of the cage. The bottom of the cage is fixed with stones as a sinker. Before putting into the cage, check whether the net clothes are damaged, soak them in water 7 days before releasing the seedlings, and then release the seedlings when there are attachments on the cage. The cage is equipped with a feeding platform with a diameter of L meters, which should be able to move freely up and down, so as to facilitate the observation of fish's feeding situation and check the fish's physique.

Second, the stocking situation

The released seedling size should be neat and free from diseases and injuries. Be careful when choosing the fry caught in the wild, because most of these fry are caught with nets such as cages, and the fry are trapped in nets for a long time, which is seriously injured and has a high mortality rate after being released. Soak fry in 1% salt and 1% sodium bicarbonate for 30 minutes. The stocking specification is 280/ kg. The stocking density was diluted three times according to the growth situation. The first stage was put into use on March 10, with a density of l000 fish/m3. In the second stage, on June 20th, when the fish quantity reaches 0/40 per kilogram/kloc, the density is adjusted to 500 per cubic meter. In the third stage, on July 25th, when the size of fish reached 80 per kilogram, the density was adjusted to 0/50 per cubic meter/kloc-until commercial fish were developed. After launching for 3 days, the fry continued to take medicine? For 5 days, povidone iodine 0.5ppm was used. Because it is a large water body, the time of each case of wine and medicine was controlled at more than 20 minutes.

Third, feeding management.

1. Feeding: self-provided feed, with crude protein content above 45%. 67% surimi and 33% powder are mixed to make soft particles, and the size of feed is constantly adjusted according to the specifications of fish, and the particle size is 3-6 mm. Fresh wild fish or chilled fish should be used for surimi, and disinfection should be carried out before processing. The fineness of powder should be above 20 mesh. The formula is: soybean meal 60%, rapeseed meal 9%, corn 20%, bran 5%, secondary flour 5%, special premix 1%. Feed it three times a day, morning, noon and evening 1 time. The feeding amount in the evening accounts for 60% of the total feeding amount in the whole day, and the daily feeding amount is 5%-7%. After feeding for 3 days, the fry began to suck, and a tapping sound was made before each feeding. After a period of domestication, conditioned reflex was formed. Start feeding

On the food table, check after 1 hour, and decide the feeding amount according to the remaining feed and the number of fish on the feed table. If there are more fish on the feed table, it means that the feed can be increased. After 10 days, the fish formed the habit of feeding at a fixed point and at a fixed time. The feeding method was changed to slowly pouring wine, gradually leading the fish to the upper layer of the water, and feeding at a depth of 20 cm below the water surface for about 30 minutes each time.

2. Escape prevention and ventilation management: check the cage 1 time every week. Because the fins of Pelteobagrus fulvidraco have hard spines, the fins open when they respond to stress, and the serrated hard spines are easy to hook the netting, which leads to the breakage of the netting when struggling, resulting in an escape accident. Thick nets are easy to be attached by algae such as moss, and the nets are blocked, so that the water inside and outside the box can not be exchanged normally, resulting in the fish not floating and lacking oxygen. When algae is attached, it should be cleaned up in time. Special attention should be paid to cleaning cages in July and August. Because of the thick mesh and strong wind resistance, it is necessary to reinforce the cage in the rainy season to prevent it from being blown down by the wind.

3. Disease prevention: The dorsal fin spines and pectoral fin spines of Pelteobagrus fulvidraco open when stimulated, and the body surface is extremely vulnerable due to scale-free protection and clustering habits. Take a bath with povidone iodine before releasing the fish. After the fish came out of the box, it was given three times in a row, and then every l5 days for two days. Anti-stress drugs are added to feed. The incidence of hemorrhagic disease is high in high temperature season, and the main symptoms are: yellow fish body surface, increased mucus, damaged and congested throat skin, swollen abdomen, red and swollen anus, congested fin base, fin ulceration and hydrops in abdominal cavity. The disease is fierce and spreads rapidly. If the treatment is not timely, the mortality rate can reach 30%. When it is found that the fish's food intake is reduced, it is immediately checked and diagnosed as hemorrhagic disease. Five days later, oral florfenicol, 0.2g/kg feed, vitamin K, etc. , 5? Seven days is a course of treatment.

Fourth, breeding achievements.

From March l0 l3 to1October 30th, after 230 days of feeding, it was caught and sold at the end of L0L3. Eight cages are 96 square meters, and 65 kilograms of fish are put in, making a total of l8200 fish. The average selling size was105g, and a total of 17836 fish were harvested, with a yield of1873kg. The fish yield per square meter is 19.5kg, the survival rate is 98%, the feed coefficient is L.96, the average price of Pelteobagrus fulvidraco is 30 yuan/kg, and the total output value is 56l90 yuan. Production cost: feed cost is l2500 yuan, fish cost is 3900 yuan, cage depreciation and medicine cost is 3000 yuan, personnel salary is 4000 yuan, profit is 23400 yuan, average profit per square meter is 243 yuan, and input-output ratio is L: L.7L.