**Abstract:**
The cultivation of Qinghai shrimp was conducted using the facilities originally designed for crab breeding. In 2001, a total of 220 million larvae were reared in the tri-foliate area. The egg-holding rate reached 93%, hatching rate was 84%, and the average breeding rate was 33%. The average density of seedlings per cubic meter of water was 163,000 individuals.
**Keywords:** shrimp; nursery; egg-holding rate; hatching rate; breeding rate
**CLC number:** S966.12+2.2 | **Document code:** B | **Article ID:** 1003-1721 (2002)02-0005-02
Green shrimp (*Macrobrachium nipponense*), also known as Japanese Macrobrachium, is a crustacean belonging to the decapod family. It is one of China's high-value aquatic products. Due to overfishing, natural populations have declined significantly, leading to rising market prices and an imbalance between supply and demand. Artificial breeding has become essential for sustainable development. The key challenge in shrimp farming is the reliable supply of seedlings. In 2000, we initiated large-scale nursery trials using the existing crab breeding facility, successfully cultivating green shrimp. Building on this success, further improvements were made in 2001, and the results are presented here.
**1. Materials and Methods**
**1.1 Breeding Conditions**
The nursery was an artificial brackish water system originally used for crabs, including storage tanks, monocellular algae culture ponds, rotifer breeding ponds, indoor nursery ponds, and broodstock holding pools. These were housed in a 1000 m² enclosed greenhouse with glass tops. Two 2 kW Roots blowers and two heating boilers were installed to maintain optimal conditions. Water was sourced from Lake Plano (660 hm²).
**1.2 Broodstock Rearing**
A temporary outdoor cement pool (160 m², 1.5 m deep) was used for broodstock holding. Water was filtered through a 100-mesh sieve, and shelter materials like stones, rubble, and bamboo branches were added. Plants such as peanuts or water hyacinth were placed at the corners. Broodstock were selected from Dongting Lake, with body lengths over 3 cm and tail weights above 4.2 g.
**1.3 Feeding and Management**
Broodstock were fed twice daily—8% of their body weight in the morning and afternoon. The diet included soybean meal, corn flour, small fish, snail meat, and cooked egg yolk. Daily cleaning and water changes were performed, along with regular aeration and water quality monitoring. Lime water and antibiotics were used to prevent disease. When eggs became transparent and heart rates increased, broodstock were moved to nursery ponds.
**1.4 Biofeeding**
Monocellular algae (e.g., *Cyclotella sp.*) were cultured in 4 m² indoor tanks. Nutrients were added gradually, and the algae were harvested when concentrations reached 1800–2000 million/mL. Rotifers (*Brachionus* spp.) were raised in separate tanks and fed with algae and soy milk. Freshwater copepods were collected and prepared for later larval stages.
**1.5 Larval Cultivation**
Nursery ponds (15 m², 1.5 m depth) were equipped with air stones for aeration. Algae and rotifers were introduced as initial feed. Larvae were transferred once they reached 500,000 per m³. Feed types changed based on larval stage, from algae to rotifers and finally to snail meat. Water quality was monitored regularly, and disease prevention measures were implemented.
**2. Results**
Using 1500 kg of broodstock (including 1200 kg females), the egg-holding rate was 93%, with about 3,000 eggs per female. In 2001, 670 million juveniles were hatched from 450 m³ of nursery water, with an 84% hatching rate. Around 200 million seedlings were grown to 1 cm, with an average breeding rate of 33%, reaching up to 41% in some batches.
**3. Discussion**
Previous studies focused on small-scale indoor trials or pond-based systems, which had low survival rates and limited scalability. This study utilized underused crab breeding facilities, achieving high breeding rates and stable production. Combining biological and artificial feeds improved cost efficiency and larval health. A new method of separating broodstock from larvae reduced mortality compared to traditional cage methods. Additionally, shading techniques helped control light exposure, enhancing larval activity and survival.
This research highlights the potential of repurposing existing aquaculture infrastructure for shrimp farming, offering a practical and scalable solution for the industry.
Multi-Thread 23G38mm,Multi-Thread 23G38mm Bolt,Multi-Thread 23G38mm Drill,Thread Pdo
Qingdao Beautiful Skin Biotechnoly Co., Ltd , https://www.hafilleresthetic.com