I. Source Selection and Preprocessing of Live Food

1. Source Identification
   • Bloodworms (red larvae): Prioritize farmed chironomid larvae; avoid wild individuals from polluted waters.
     
   • Daphnia: Preferably cultivated in green water (rich in Chlorella); a light red color indicates adequate nutrition.
   • Mosquito larvae: Ensure the collection area is free of pesticide residues (test for organophosphates using test strips).
2. Health Grading
   • Grade A: Strong activity, intact body surface, no abnormal odor.
   • Grade B: Sluggish activity but intact body surface (requires enhanced disinfection).
   • Grade C: Dead or mucus-covered individuals (discard directly).

II. Stepwise Disinfection and Sterilization Process

III. Nutritional Enhancement and Carrier Processing

1. Vitamin Enrichment Protocol
   • Base solution preparation: Add 50 mg vitamin B complex, 100 mg vitamin C ester, and 0.1 g β-glucan per liter of clean water.
   • Enrichment operation: Place disinfected live food in the enhancement solution for 2 hours (water temperature 20°C with continuous aeration).
2. Probiotic Loading Technique
   • Soak in Bacillus subtilissuspension (10⁸ CFU/mL) for 30 minutes.
   • Increases beneficial bacteria content in the live food's gut, creating a "bio-capsule" feeding effect.

IV. Freezing Treatment and Thawing Standards

1. Freezing Inactivation Parameters
   • Flash freezing temperature: -35°C for 2 hours → transfer to -18°C storage for 46 hours.
   • Parasite elimination rate: 99.7% (targeting Lernaea, Dactylogyrus, etc.).
   • Nutrient retention rate: Protein ≥95%, vitamins ≥85%.
2. Scientific Thawing Method
   • Stepwise thawing: -18°C → 4°C (12 hours) → 15°C water bath for 3 minutes.
   • Dehydration treatment: Drain using a 200-mesh sieve, lightly press with gauze to remove surface ice crystals.

V. Feeding Implementation Standards

1. Feeding Proportion Control
   • Juvenile stage (≤15 cm): 8–10% of daily ration, once weekly.
   • Sub-adult stage (15–40 cm): 5–8% of daily ration, twice weekly.
   • Adult stage (≥40 cm): 3–5% of daily ration, once weekly.
2. Timing and Environmental Requirements
   • Optimal period: Sunny mornings at 10:00 AM when water temperature is 20–25°C.
   • Supplementary measures: Add an airstone in the feeding area; remove uneaten food after 2 hours.
3. Adjustments for Special Conditions
   • Pre-spawning period: Increase daphnia feeding (rich in gonadotropins).
   • Post-operative recovery: Avoid bloodworms (prone to causing infection); use disinfected brine shrimp instead.

VI. Risk Monitoring and Emergency Response

1. Post-Feeding Monitoring Indicators
   • Observe fecal morphology within 2 hours (stop feeding immediately if transparent mucus-coated feces appear).
   • Daily testing for Vibriolevels in water (simple test strip method, threshold <10³ CFU/mL).
2. Abnormal Situation Handling
   • Enteritis symptoms: Fast for 3 days, feed medicated feed with 0.5% allicin.
   • Parasite outbreak: Use trichlorfon (0.3 ppm) in the entire pond and implement UV circulation sterilization.

VII. Alternatives and Innovative Technologies

1. Development of Live Food Substitutes
   • Microbial capsule feed: Slow-release pellets containing encapsulated brine shrimp, spirulina, and probiotics.
   • Artificially cultivated sterile daphnia: Sterilized with γ-ray irradiation and colonized with probiotic strains.
2. Automated Feeding Systems
   • UV real-time sterilization conveyor belts.
   • Quantitative feeding robots (error <0.1 g).