GB/T 21047-2026Red drum (English PDF)

Foreword

This document complies with the provisions of GB/T 1.1-2020 "Standardization Work Guidelines Part

1.Structure and Drafting Rules of Standardization Documents". Drafting. This document replaces GB/T 21047-2007 "Eye-spotted Sciaenia". Compared with GB/T 21047-2007, the only changes are structural adjustments and editing. Aside from the sexual alterations, the main technical changes are as follows:

a) The "Category" has been changed (see 4.2,

3.2 in the.2007 edition);

b) The formula relating fork length (weight) to growth time and the measured values of body length and weight for different age groups have been removed (see section

5.2 of the.2007 edition);

c) The measurable and countable traits have been modified (see

5.1.2 and 5.1.3, and

4.1.3 in the.2007 edition);

d) The formula for the relationship between body length and weight has been modified (see 6.1,

5.3 in the.2007 edition);

e) The "age of sexual maturity" has been changed (see 6.2.1,

6.1 in the.2007 version);

f) "Sexual maturity and body length" has been removed (see

1 Scope

GB/T 21047-2026 is the Chinese national standard covering red drum as a farmed fish - an American species now widely grown in Chinese cage culture, with its grades, its condition and the freshness requirements. It replaces GB/T 21047-2007 and has been in force since 1 September 2026. It was issued on 27 February 2026 and has been in force since 1 September 2026, replacing GB/T 21047-2007. The document is under the responsibility of the Ministry of Agriculture and Rural Affairs. This page is published from the official record of the 2026 edition; the clause text of a standard this recent is not yet in circulation, and the figures, limits and tables it contains are those of the document itself, delivered in full with the English translation.

The characteristics, growth and reproduction properties, cytogenetic properties, molecular genetic properties, and judgment rules are described, along with the corresponding detection methods. This document applies to the germplasm identification and testing of the spotted totoaba.

6 Growth and Reproduction Characteristics

6.1 Growth The relationship between body length and weight of the eye-spotted croaker (2.10cm~55.17cm) is shown in equation (1).

7 Cytogenetic characteristics

7.1 Number of chromosomes Somatic cell chromosome number. 2n=48.

7.2 Karyotype The karyotype formula is 2n=48t, and the number of arms NF=

48.The chromosome karyotype is shown in Figure 2.

8.Molecular genetic characteristics The base sequence of the mitochondrial COI gene fragment (652 bp). CCTCTACCTA GTTTTCGGTG CATGAGCCGG AATAGTAGGC ACAGCCTTAA GCCTTCTAAT 60 CCGAGCAGAA CTAAGTCAGC CCGGTGCACT CCTCGGAGAT GACCAAATTT ATAACGTAAT 120 TGTTACGGCG CATGCCTTCG TTATAATTTT CTTTATAGTA ATGCCCATTA TGATTGGAGG 180 TTTCGGGAAC TGACTCGTAC CCTAATGAT TGGAGCCCCC GACATGGCAT TCCCCCGAAT 240 AAATAATATG AGCTTCTGGC TTCTTCCCCC ATCTTTCCTT CTTCTCCTTA CCTCCTCAGG 300 TGTAGAGGCA GGGGCCGGAA CAGGATGAAC AGTTTACCCT CCACTCGCCG GAAACCTTGC 360 ACACGCAGGA GCTTCCGTCG ACTTAGCCAT CTTTTCCCTC CACCTCGCGG GTGTTTCATC 420 AATTCTGGGG GCCATTAACT TTATCACAAC AATCATTAAC ATAAAACCCCCCGCTATTTC 480 CCAGTATCAG ACACCTTTTAT TTGTATGAGC TGTATTAATT ACAGCCGTTC TTCTACTTCT 540 ATCCCTCCCT GTCTTAGCTG CCGGCATTAC AATACTCCTG ACAGACCGCA ACCTCAATAC 600 AACCTTCTTC GACCCAGCAGGAGGGGGAGA CCCGATCCTC TACCAACATC TG 652 Intraspecific K2P (Kimura2-parameter) genetic distance should be less than 2%.

9 Detection Methods

9.1 Sampling Perform in accordance with the provisions of GB/T 18654.2.

10 Judgment Rules

10.1 When the test results meet the requirements of Chapter 5, the species can be identified.

10.2 When the following situations occur, it is necessary to add the requirements of other chapters for testing, and make a comprehensive judgment on the species based on the test results.

a) When Chapter 5 cannot be tested or accurately determined, or when a third party requests it, add testing to Chapter 7 or/and Chapter 8. content;

b) When a third party requests testing of all or part of Chapter 6;

c) During full-item testing. GB/T 21047-2026. Eye-spotted Totodactylus ICS

51 National Standards of the People's Republic of China Replaces GB/T 21047-2007 Eye-spotted Totodactylus Published on 2026-02-

27 Implemented on 2026-09-

01 State Administration for Market Regulation The State Administration for Standardization issued a statement.