GB/T 39175-2020 in English

Key indicators of broodstock quality

The standard stipulates that the weight of female broodstock must be ≥60g and that of male broodstock must be ≥45g, and the breeding age must be 1+ years old. The appearance requires normal body shape and obvious reproductive characteristics, and especially emphasizes that the female fish's cloaca should be slightly reddish and swollen.

Seedling quality requirements

After the yolk sac disappears, it enters the qualified seedling stage, requirements:

• Disability rate <2%, deformity rate <1%
• Total length not exceeding 3cm
• Must pass quarantine

Fish species specification standards

Sampling and Judgment Rules

Sampling is carried out in accordance with GB/T18654.2, and the disability rate is calculated by taking the average value of three consecutive tests. If the safety index fails, the entire batch is judged to be unqualified, and re-inspection is not allowed.

Disease Diagnosis Methods

Key points for transportation

• Broodstock transportation: stop feeding for 48 hours, and maintain the water temperature at 6-8℃
• Seedling transportation: stop feeding for 24 hours, and control the water temperature at 18-20℃
• Both need to be transported in foam boxes with ice and oxygenated, and the transportation time limit shall not exceed 30 hours

Suggestions for farm management

It is recommended to establish a broodstock file management system to record:

1. Provenance certification documents
2. Regular physical examination records (focus on monitoring the diseases listed in Appendix A)
3. Reproductive performance data