Stingray, commonly known as the yellow duck or yellow ladle, is a benthic omnivorous fish renowned for its delicate and nutritious meat, making it highly valuable in the market. Its economic potential has led to the development of various breeding techniques, including seedling production, pond culture, and cage farming. Below are detailed methods for each stage:
**1. Seed Breeding**
- **Broodstock Selection**: Healthy adult stingrays with smooth skin, intact fins, and no signs of disease or injury were selected. Female broodstock should weigh between 75–100 grams, while males should be 125–150 grams. A female-to-male ratio of 1:1.2 was used for optimal breeding.
- **Artificial Spawning**: Broodstock were kept in breeding pools, where females were gently pressed on their bellies to release eggs, while males were manually stimulated to release sperm. The spawning environment included artificial nests at the bottom of the pool to prevent damage from the adults. Common hormones used include ERH2 (LRH-A2), HCG, and ketoxime.
- **Artificial Hatching**: Eggs were left to hatch naturally in spawning rings or tanks. Since stingray eggs are attached to the nest, only a gentle flow of water was maintained during hatching. Static water tanks or cages could also be used, with aeration added to ensure oxygen supply.
- **Fry Cultivation**: After hatching, fry were transferred to specialized pools. Initially, they were fed live zooplankton, followed by a mix of egg yolk and fish pulp. Once they reached 1.5 cm in length, compound feed was introduced. Fry were moved to the next stage when they grew beyond 3 cm.
**2. Pond Culture Techniques**
- **Pond Preparation**: Ponds with good water quality, sufficient depth (at least 1.5 meters), and an area of 1,500–1,700 square meters were chosen. Silt removal and disinfection with lime or bleaching powder were essential before stocking.
- **Stocking and Feeding**: Fish were stocked in winter or early spring, with a density of 2,000–3,000 fish per 667 square meters. A salt bath was applied before stocking to reduce stress and disease risk. Feed consisted of minced fish, shrimp, and plant-based ingredients, with daily feeding amounts ranging from 5% to 8% of the fish's body weight.
- **Water Quality Management**: Water was changed every 10–15 days, and regular monitoring ensured optimal conditions. Disease prevention involved periodic application of bleaching powder, with careful use of medications due to stingrays' sensitivity.
**3. Cage Culture Techniques**
- **Location Selection**: Cages were placed in sheltered areas with water depths of at least 4 meters, such as bays, lakes, or rivers.
- **Cage Construction**: Made from polyethylene netting, cages measured 3x3x1.6m or 4x4x1.6m. They were anchored with ropes and arranged in a "one" or "goods" pattern.
- **Stocking Density**: Fish were stocked at 100 tails per square meter for 25g fish and 70 tails per square meter for 50g fish. A salt bath was used before introduction into the cages.
- **Feeding and Maintenance**: Daily feeding was split into two parts—60% in the evening and 40% in the morning. Cages were cleaned weekly, and nets were checked daily for damage. Shade nets were added during hot seasons to protect the fish.
- **Disease Prevention**: Although stingrays are less prone to diseases, regular cleaning and lime water applications helped maintain health and prevent outbreaks.
These comprehensive techniques ensure successful stingray farming, supporting both commercial viability and sustainable aquaculture practices.
Growth Promtor
Growth Promtor,Growth Promoter For Poultry,Growth Promoter Hormone,Growth Promoter For Cattle
Sichuan Aibang Weiye Biological Engineering Co., Ltd. , https://www.aibangpharm.com