International Journal of Aquaculture, 2025, Vol.15, No.2, 76-87 http://www.aquapublisher.com/index.php/ija 79 peptide genes), providing clues for molecular marker development and functional verification (Table 1). In the field of heat resistance, studies have compared the gene expression differences of hybrid abalone and their parents under heat stress, and found that hybrid abalone exhibits many non-additive expression genes, which may explain its heat resistance hybrid advantages (Boamah et al., 2024). Metabolomics also plays an increasingly important role in the study of abalone’s adaptability and quality. By analyzing the changes in small molecule metabolites of abalone under different environmental conditions or nutritional levels, we can gain an in-depth understanding of its physiological metabolic mechanism. Some studies have compared the metabolites spectrum of wrinkle disc abalone after acute high temperature stress in the low-temperature domestication group and the room-temperature domestication group. It was found that high temperature will lead to impaired mitochondrial function, incomplete oxidation of amino acids and fatty acids, and accumulation of large amounts of unstable metabolic intermediate products (Nguyen et al., 2022). This metabolomic evidence reveals the biochemical adaptation mechanism of abalone's heat-resistant domestication, which is of guiding significance for cultivating heat-resistant strains. Table 1 Summary of transcriptome data quality Sample RawReads Clean Reads Q20 (%) Q30 (%) A0h_1 49956086 48345146 97.80 93.78 A0h_2 60683246 59898532 97.87 93.80 A0h_3 61470694 60069372 97.92 93.99 A8h_1 51587050 50699510 97.92 94.03 A8h_2 52928692 49932234 97.59 93.30 A8h_3 58296146 55617338 97.99 94.16 A48h_1 56932668 55630668 97.81 93.76 A48h_2 53354632 49324524 97.97 94.06 A48h_3 51494542 50737750 98.01 94.12 3.3 Genetic marker development: comparative analysis of SNP, SSR and InDel Molecular genetic markers are a key tool to connect genomic information with breeding practices. Early molecular breeding research on abalone mainly relies on microsatellite markers (SSR) and amplified fragment length polymorphisms (AFLP), etc., for population genetic diversity analysis, genetic linkage map construction and pedigree identification. Due to its co-dominant and multi-allelic characteristics, SSR markers have played an important role in small-scale genetic monitoring (Liu and Huang, 2024). However, the number of SSRs is limited, unevenly distributed, and the detection throughput is low, making it difficult to automate. With the improvement of abalone reference genomic data, it is possible to develop high-density SNP markers. For example, based on high-deep resequencing data, hundreds of thousands of high-quality SNP sites can be screened out in the wrinkle disc abalone genome. The abalone SNP chip developed in recent years has greatly improved the efficiency and consistency of genotyping: Korean researchers have developed a 60K abalone custom chip containing 65,740 SNP sites, and the average classification success rate is 90.47%, and the polymorphic SNP ratio is 76.03% (Kho et al., 2021). China also has an independently developed 40K liquid phase capture chip to achieve target capture and sequencing of nearly 88 000 SNP sites in the abalone genome. Compared with traditional SSR markers, SNP chips have the advantages of high flux, wide coverage, good stability and easy to detect automatically; compared with conventional solid-phase SNP chips, liquid-phase capture chips are easier to operate, lower cost and have high flexibility. Therefore, in the whole genome selection of abalone, SNP markers have become the main force. A patent has reported a method to identify the inherited male and female wrinkle disc abalone by detecting base deletion at specific sites (Luo et al., 2021). InDel markers tend to have the advantage of being simple and intuitive (electrophoretic and discernible length differences), but are relatively small in number. 4 High-Throughput Technical Support System in Abalone Breeding 4.1 High-throughput phenotypic analysis platform and underwater imaging technology Phenotype determination is the basis of breeding, but as marine shellfish, the traditional measurements of abalone
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