Detailed Explanation of Key Points of Ecological Farming Techniques for the Barbel Steed (Squaliobarbus curriculus)

The barbel steed (Squaliobarbus curriculus), also known as the red-eye, belongs to the order Cypriniformes, family Cyprinidae, subfamily Leuciscinae, and is a valuable wild economic fish of the Yangtze River. Its body is elongated and cylindrical, with a rounded belly and a somewhat laterally compressed rear portion; its body color is silvery white, the back is slightly dark gray, and there is a prominent red spot on the upper rim of the eye, hence the name red-eye.

The barbel steed has strong adaptability, is omnivorous, and grows quickly. It lives in the middle and upper layers of the water body, and its requirements for water temperature and dissolved oxygen are basically the same as those of the four major Chinese carps. It has no special requirements such as overwintering and is easy to farm artificially. The barbel steed has tender, delicious flesh and is well received by consumers.

We conducted a grow-out farming trial. The pond areas were 4 mu and 7 mu respectively, with a water depth of 1.5-2 m, about 20 cm of pond bottom mud, convenient water inlet and drainage, and a water source from the Yangtze River. In late February 2004, the ponds were drained, the ponds were cleaned and leveled, and 100 kg of quicklime per mu was used for disinfection. After disinfection, water was let in through a filter, and 150 kg of fermented chicken manure base fertilizer was applied per mu.

Fish Stocking

1. On March 5, barbel steed fingerlings with a size of 12-14 cm and a body weight of about 30 g were stocked: 3,000 fish in Pond No. 5, at 750 fish per mu, and 5,500 fish in Pond No. 7, at 786 fish per mu. At the same time, 150 silver carp and bighead carp with a size of about 100 g were stocked. Before stocking, the fish bodies were disinfected with 3% salt water.

2. Co-stocking with freshwater shrimp. The target yield of the trial ponds was only about 400 kg per mu, of which barbel steed accounted for 300 kg and silver carp and bighead carp for 100 kg, so the water quality conditions were relatively good. Freshwater shrimp also have water quality requirements similar to those of the barbel steed, creating the basic conditions for co-stocking freshwater shrimp, and the reproduced shrimp fry also provided natural animal feed for the barbel steed. About 4 kg of juvenile shrimp at 2,000-3,000 shrimp per kg were stocked per mu.

Feed Feeding

The feed used was general-purpose floating pellet feed for intensive fish farming, with a crude protein content of 30%. It was fed once each in the morning and afternoon every day, with a feeding amount of 3%-5% of the pond fish body weight. The specific feeding amount was based on basically finishing the feed within 25 minutes after feeding. Fixed-point feeding was implemented, and the feed was placed in a square-frame feeding stand enclosed by moso bamboo. The barbel steed has an obvious habit of chasing food, so fixed-point feeding is especially easy to tame; generally, it can be narrowed down from broadcast feeding to the feeding stand in 3 days.

In addition to feeding floating pellet feed every day, in line with the barbel steed's feeding habit of liking green feed, a certain amount of duckweed was kept in the pond or appropriately added every day to meet the barbel steed's demand for green feed.

Water Quality Management

The pond water transparency was required to be basically controlled at 25-30 cm, so as to keep the water quality fresh, lively and clear. Starting from April, new water was gradually added to raise the water level, reaching about 2 m in the high-temperature season. From April to May, new water was added once every 10-15 days, 5-10 cm each time. In the high-temperature season after June, new water was added once every 7-10 days, generally 10-15 cm each time depending on the water quality. Management of the water body environment was also strengthened, weeds around the pond were cleared, debris and leftover feed in the water were promptly removed, and the sanitation of the feeding area was maintained, ensuring good water quality requirements.

Disease Prevention and Control

1. Splash Ludisanjunning once a month to sterilize and disinfect the water body.

2. Use quicklime once about every 20 days, at 10 kg per mu.

3. Use a microecological preparation once every half month in the high-temperature season.

4. Fish diseases were detected in a timely manner and treated according to the symptoms, achieving good disease prevention and control results. During the entire farming period, parasitic disease caused by anchor worms was found only once in Pond No. 7 in mid-June, and the insecticide Aweishate was immediately used for treatment, with very good results.

Yield

The total yield of fish and shrimp in Pond No. 5 was 1,703.6 kg, averaging 425.9 kg per mu. Among this, barbel steed averaged 302.7 kg per mu, with an average body weight of 416 g; silver carp and bighead carp averaged 103 kg per mu, with an average body weight of 710 g; and freshwater shrimp were 20.2 kg.

The total yield of fish and shrimp in Pond No. 7 was 2,874.9 kg, averaging 410.7 kg per mu. Among this, barbel steed was 291.5 kg, with an average body weight of 385 g; silver carp and bighead carp were 102.2 kg, with an average body weight of 730 g; and freshwater shrimp were 17 kg.

Benefits

The total sales income was 78,579.94 yuan, of which barbel steed was 68,277.3 yuan, accounting for 86.9%; silver carp and bighead carp were 4,509.6 yuan, accounting for 5.7%; and freshwater shrimp were 5,793.04 yuan, accounting for 7.4%. The sales income per mu was 7,143.63 yuan, of which barbel steed was 6,207.03 yuan (21 yuan/kg). The total production cost was 35,922.15 yuan, and the cost per mu was 3,265.65 yuan (fingerling cost 888 yuan, feed 1,557.65 yuan, pond rent 400 yuan, water, electricity and medicine 220 yuan, other 200 yuan). The total benefit was 42,657.79 yuan, and the average benefit per mu was 3,877.98 yuan.

Summary

1. The combination of mainly feeding compound pellet feed, supplemented by duckweed and co-stocked freshwater shrimp to provide natural animal and plant feed, effectively improved feed utilization and reduced the feed conversion ratio.

2. Appropriately reducing the yield level, combined with a farming model of filter-feeding fish and co-stocked freshwater shrimp and a water quality regulation technique based mainly on adding new water, reflected the comprehensive effect of ecological farming.