1 Introduction

Channa spp., also known as black fish, is also called "snakehead fish". This fish is actually quite common in Asian waters. Especially in China, Vietnam, India and other places, the aquaculture industry relies heavily on it (Kumar et al., 2022). As a "bottom-dwelling omnivorous double-respiring fish", it has strong adaptability and can survive well in low-oxygen environments, mainly due to its "amphibious" breathing method. It grows fast, has a high protein content in its meat, and is very profitable to farm (Harrington et al., 2022; Cui et al., 2024). It is precisely because of these advantages that Channa has always been an important source of daily protein intake for people in areas where fish is the staple food.

But to be honest, the domestication process of snakehead is not easy. As the global demand for high-quality aquatic products grows year by year, how to cultivate snakehead varieties that are more suitable for high-density farming, grow faster, and have strong disease resistance has become a common problem facing researchers and farmers (Cui et al., 2024; Liu et al., 2024). At present, many countries have launched selective breeding programs, but the problem is that it is not that simple to turn wild snakehead into "domestic fish".

One prominent problem is that it is highly aggressive. Studies have found that the cannibalism rate of domesticated species in Vietnam during the hatching period is not low, reaching 40%-42%; and the wild population in the Mekong River in Cambodia is even more exaggerated, with a cannibalism rate of up to 57% (Nen et al., 2018). This kind of "cannibalism" behavior is a big challenge to aquaculture management. In addition to this, it is also not adaptable to the captive environment, such as slow growth, unstable reproduction, poor group performance, etc., which directly affect the progress of breeding (Cui et al., 2024).

Ultimately, many traits are actually based on genetics. We have not yet fully understood which genes in snakehead fish are linked to which traits. Although some studies have begun to use tools such as genome-wide association analysis (GWAS) and genomic selection to explore key genetic markers for growth, reproduction, and adaptability, the overall progress is still in the exploratory stage (Sodsuk, 2012; Liu et al., 2024).

The purpose of this study is to start with the genetic diversity of the population and combine the latest genomic tools to screen candidate genes that can guide snakehead breeding. We hope that these results can truly lay the foundation for the selection and breeding of snakehead species, and also provide support for improving the overall efficiency of aquaculture and ensuring protein supply.

2 Overview of Channa Domestication

2.1 History and current status of Channa domestication

Channa species, especially Channa striata, have traditionally relied mainly on wild resources for aquaculture and ornamental purposes, but this dependence has also raised concerns about overexploitation of natural habitats and population decline. Wakiah et al. (2020) analyzed 1 594 individuals from Lake Tempe, Indonesia, and found that its exploitation rate was 0.55, which was close to or even exceeded the maximum sustainable exploitation limit (usually E=0.5 is the overfishing warning line), reflecting the obvious resource development pressure in the region. Domestication efforts in recent years have increasingly focused on providing fry through artificial breeding to reduce dependence on wild populations and ensure a sustainable supply of fry for aquaculture. Artificially bred Channa differ from wild populations in growth rate and survival rate. Although artificial strains generally perform better in aquaculture environments, the genetic mechanisms behind these differences are still under study (Ndobe et al., 2018; Kumar et al., 2022).

Domestication of Channa is particularly active in Southeast Asia, including countries such as Indonesia, Vietnam and Cambodia. In Indonesia, domestication of local Channa species has been successful, but further optimization of their growth and survival in aquaculture systems remains a challenge (Saputra and Mahendra, 2019; Saputra et al., 2022). In Vietnam, advances in seedling propagation technology and selective breeding have promoted more sustainable aquaculture practices and have supported the development of a local industry in neighboring Cambodia through technology transfer after policy adjustments (Hien et al., 2017; Kumar et al., 2022).

2.2 Key traits targeted during domestication

Improving growth rate, body size and feed utilization are the main goals of domestication of Channa. Studies have shown that growth performance varies greatly between different feed types and genetic strains, and artificial strains are generally better than wild strains in controlled environments. In a comparative experiment conducted in Cambodia, domesticated C. striata and wild species were fed pelleted feed (40% protein), and domesticated fish showed better results: final weight: 367 g (domesticated) vs. 233 g (wild); survival rate: 75% (domesticated) vs. 69% (wild); FCR (feed conversion ratio): 1.5 (domesticated) vs. 1.7 (wild); income: $0.35/kg (domesticated) vs. $0.25/kg (wild).

Optimizing feed conversion rate and growth rate, including the application of probiotics and compound feed, is a research hotspot for improving breeding efficiency (Nen et al., 2018; Saputra and Ibrahim, 2021; Saputra et al., 2022). Dewi et al. (2023) found that after treating feed with EM4 probiotics (10 mL/kg), the FCR of Channa striata was 1.56, the growth rate was 1.85 g/30 days, and the survival rate was as high as 97.78%.

Reproductive performance and stress resistance are also key breeding indicators. Improving gonadal maturity and induction success rate through hormone induction (such as FSH, LHRHa, Buserelin) has become an important means to promote artificial reproduction. At present, a series of technical solutions have been developed to improve the spawning rate, embryo survival rate and hatching rate of Channa, so as to achieve the controllability of seed production and adapt to high-density breeding systems (Azrita et al., 2015; Kumar et al., 2022).

For example, Awal et al. (2024) used Channa striata in Bangladesh as the object to explore the effect of inducing artificial reproduction using natural carp pituitary extract (CPE) and synthetic hormone Buserelin (Buserelin) (Figure 1) (Awal et al., 2024). The results showed that both hormones can promote spawning, fertilization and hatching, among which high-dose treatment (CPE: 80 mg/kg, Buserelin: 0.80 μg/kg) has the best effect.

2.3 Genetic consequences of domestication

The shift from wild resources to factory seed production may lead to a decrease in genetic diversity due to genetic drift and inbreeding, especially when broodstock are not properly managed. High levels of population differentiation (FST = 0.21902-0.49428) and small effective population size (Ne) were found in nine Channa argus populations in central China, indicating that artificial release and hatchery operations may have caused local genetic drift and long-term genetic structure changes (Yan et al., 2018). Fan et al. (2022) compared three artificially cultured "white type" Channa argus and four "two-color type" Channa argus and found that the haplotype diversity (Hd = 0.505) and nucleotide diversity (Pi = 0.000 57) of artificially bred populations were much lower than those of wild populations (Hd = 0.911, Pi = 0.003 26). The reduction in genetic variation may affect the long-term adaptability and survival fitness of the population. Therefore, continuous genetic monitoring must be carried out during the domestication breeding process (Nen et al., 2018; Kumar et al., 2022).

Selective breeding for traits such as fast growth and high feed efficiency, may lead to a phenomenon called “genomic erosion”, in which alleles associated with non-target traits are lost during the breeding process. This situation may weaken the overall genetic health of artificial populations and limit their ability to respond to environmental changes or disease outbreaks (Nen et al., 2018; Kumar et al., 2022).

3 Genetic Variability of Key Traits in Channa Domestication

3.1 Growth and feed efficiency traits in Channa

A genome-wide association study (GWAS) conducted on fish of the genus Channa found that multiple single nucleotide polymorphisms (SNPs) and candidate genes were significantly associated with growth traits. In Channa maculata, a total of 51 important SNP loci associated with growth traits such as body weight and body length were identified, among which the HS6ST1 gene was closely associated with traits such as body weight, body length, and total length (Liu et al., 2024). Other candidate genes are related to biological processes such as organelle formation, signal transduction, cell proliferation, and muscle growth, providing a theoretical basis for marker-assisted selection in breeding programs.

Growth-related traits in Channa maculata showed moderate to high heritability, with most traits estimated to be between 0.22 and 0.52, all of which were moderate to highly heritable, and only one trait had a heritability of 0.108 1 (Liu et al., 2024). This result shows that it is feasible to improve feed conversion efficiency and growth performance through selective breeding, and it is expected to achieve genetic progress in artificially domesticated populations. The all-male NBS produced based on sex control and hybrid breeding has a feed conversion rate (FCR) that is 12.5%-17.6% lower than that of mixed-sex NBS and 72.3% lower than that of purebred Channa. Moreover, the proportion of individuals weighing more than 1 kg reached 91.3%-96.4%, which was significantly higher than that of the control group (Ou et al., 2021), indicating that it also has great potential in growth efficiency and economic benefits.

3.2 Reproductive traits and sex differentiation in Channa

Channa spp. show a wealth of molecular regulatory mechanisms in the mechanism of sex differentiation, such as the sex-specific expression of genes such as Foxl2, Amh, and Cyp19a1a, which are affected by epigenetic regulation. In Channa argus, the Foxl2 gene is strongly expressed in the ovary during the early stage of gonadal differentiation, indicating that it plays a key role in female differentiation (Wang et al., 2015). Similarly, in C. argus, the expression of the Amh gene in male testes is significantly higher than that in females, with XY males expressing 36.03 times (P<0.01) 90 days after hatching, while females remain at a low level; after treatment with estrogen, the expression of Amh in XY sex-changed females is downregulated to a level similar to that of XX females (Luo et al., 2020).

A high-density genetic linkage map constructed in Channa maculata revealed major loci closely related to sex determination. A single major locus located on linkage group 2 (LG2) explains almost all the variation in trait expression, indicating that its sex determination mechanism conforms to the XX/XY chromosome system. This discovery provides a genetic basis for regulating sexual maturity and developing sex-controlled breeding strategies (Liu et al., 2021). In this sex-linked region, the study identified four markers that are heterozygous in males and homozygous in females, and also verified a sex-specific SNP marker that can be used for actual sex identification.

3.3 Stress resistance and immunity in Channa strains

Channa have strong environmental adaptability, and their immune systems show rhythmic regulation, stress response to pollutants, and positive immune response to nutritional intervention. In the study of Channa punctatus, it was found that the phagocytosis, superoxide anion production, and nitrite release of immune cells (such as macrophages and lymphocytes) in its head kidney and spleen showed obvious annual rhythms, and immune function peaked from October to March, suggesting that fish adapt to seasonal stress through immune rhythms (Chandra et al., 2023).

Verma et al. (2015) found that after Channa punctata consumed a diet containing 5% fig and acacia plant powder, its serum superoxide dismutase (SOD), nitrate, nitric oxide and phagocytic activity increased, and its immunoglobulin content also increased, enhancing its resistance to A. hydrophila. Another study found that after Channa argus consumed a diet containing 50-100 mg/kg astaxanthin, the activity of antioxidant enzymes (SOD, CAT, GSH-Px) increased, the expression of pro-inflammatory factors (TNF-α, IL-1β) decreased, and the survival rate against A. hydrophila increased to 58% (Li et al., 2019).

4 Genomic and Transcriptomic Tools for Trait Mapping in Channa

4.1 Genome-wide studies of trait variation in Channa

With the help of advanced sequencing technologies such as 2b-RAD, researchers have constructed high-density genetic linkage maps for the genus Channa. These maps contain thousands of SNP markers, making genome-wide studies of trait variation possible and helping to identify quantitative trait loci (QTLs) associated with economic traits (such as growth and sex determination). For instance, Liu et al. (2020) used 2b-RAD technology to construct a linkage map containing 3 151 SNP markers, covering 24 linkage groups with a total length of 2 728.9 cM and an average spacing of 0.87 cM. A total of 14 QTLs related to body weight and body length were detected, and the phenotypic variation explained by a single QTL was 9.6%-12.8%. The sex determination locus is concentrated in LG5, which can explain 97.4%-100% of the phenotypic differences and confirm the XX/XY sex determination system.

Similarly, the high-density map constructed based on 2b-RAD contains 6 352 SNP markers distributed in 21 linkage groups, with a total map length of 2 143.7 cM and an average marker spacing of 0.34 cM. Nine QTLs related to body weight were found, which can explain 9.8%-11.9% of the phenotypic variation. The sex-related major effect QTL was located in LG2, explaining 98.8%-100% of the phenotypic differences, supporting the XX/XY system (Liu et al., 2021). The study also found that candidate genes such as SATB2 and BMP6 were located in the QTL interval, becoming important genetic markers for marker-assisted selection and breeding improvement.

4.2 Transcriptome analysis in Channa under selective pressure

Gene-based association methods, such as PrediXcan, use reference transcriptome data to link genetically regulated gene expression to phenotypic traits. These methods can identify key genes that lead to differences in growth rate, providing new insights into the molecular mechanisms between fast and slow growth phenotypes (Gamazon et al., 2015; Nagpal et al., 2019).

Technologies such as transcriptome-wide association studies (TWAS) and single-cell RNA sequencing (scRNA-seq) can analyze changes in gene expression in Channa when faced with environmental stresses (like high temperature or immune challenges) (Nagpal et al., 2019; Cuomo et al., 2021). These tools not only help map expression quantitative trait loci (eQTLs), but also reveal regulatory networks involved in stress and immune responses, providing support for breeding more stress-resistant Channa strains.

5 Breeding Strategies for Genetic Improvement of Channa

5.1 Marker-assisted selection (MAS) in Channa

Through genome-wide association studies (GWAS) and SNP chip technology, researchers have identified quantitative trait loci (QTLs) associated with growth traits in Channa, enabling the screening of individuals with better growth performance. For example, in Channa maculata, SNPs screened using GWAS improved the prediction accuracy of body weight and total length, indicating that MAS has great potential in accelerating the genetic progress of growth traits (Cui et al., 2024). Although the disease resistance QTLs of C. maculata have not been reported in detail, the application of MAS to integrated breeding for dual traits of growth and health is considered a worthy direction for development.

The practical application of MAS in hatchery farms is increasing, and sex-related and growth-related genetic markers are widely used for screening parents and offspring. With the development of next-generation sequencing (NGS) technology, researchers have developed sex-specific molecular markers that can effectively identify sex genotypes, thereby achieving the production of all-male fish stocks, which usually have faster growth rates and higher economic value (Ou et al., 2017; Sun et al., 2023).

5.2 Genomic selection (GS) for Channa productivity

Genomic selection (GS) uses genome-wide SNP data to estimate genomic breeding values (GEBVs) of traits, such as weight and length of fish. A GS simulation study on Epinephelus coioides evaluated the predictive ability of four algorithms (gBLUP, rrBLUP, BayesA, BayesC) under different conditions and found that the average AUC value was between 0.547 and 0.548, and the predictive ability of each method was similar (Ma and You, 2020). In C. macrochirus, the heritability estimates for these traits were moderate (0.29-0.31), while GS models such as GBLUP and BayesB showed high prediction accuracy when using GWAS-screened SNP datasets (Cui et al., 2024).

GS also supports the use of low-density SNP marker combinations for prediction while maintaining high prediction accuracy, making it more cost-effective in large-scale breeding. Combining GWAS with GS can further improve selection accuracy, even in strains with diverse genetic backgrounds, thereby accelerating the promotion and application of GS in aquaculture breeding (Cui et al., 2024).

5.3 Hybridization and strain improvement in Channa

Interspecific hybridization of Channa spp., such as the mating of Channa argus and Channa maculata, has produced hybrids that are superior to their parents in growth rate, survival rate, and stress resistance. The all-male hybrids obtained through sex control and cross breeding have an average daily weight gain of up to 17% and show a significant male-biased sex ratio, thereby maximizing economic benefits (Ou et al., 2018; Zhao et al., 2021).

Hybrid strains combine the excellent traits of both male and female parents, like rapid growth, strong feed adaptability and low temperature tolerance, making them of great application value in diversified breeding environments. Ou et al. (2018) showed that the average weight of the hybrid NBS (C. argus ♀ × C. maculata ♂) at six months of age was (421.3 ± 72.9) g, which was 124.6% and 71.5% higher than the maternal NS (187.6 ± 42.8) g and the paternal BS (245.6 ± 52.5) g (P<0.05), respectively, showing obvious hybrid vigor. The study also found that the hybrid inherited the easy training of BS and could quickly adapt to artificial formula feed; in the wintering experiment, even if the water temperature dropped to 0 °C-2 °C, the hybrid showed a similar high survival rate as NS, indicating that it has strong low temperature tolerance.

6 Case Studies

6.1 Genetic analysis of growth traits and breeding recommendations in Channa

In the process of Channa domestication and breeding, growth traits are key indicators affecting economic benefits. However, molecular breeding research on this genus is still in its infancy, especially in terms of genetic variation and candidate gene screening. Liu et al. (2024) conducted the first genome-wide association study (GWAS) of growth-related traits by whole-genome resequencing and growth trait measurement of 500 Channa maculata, and identified 51 significant SNP loci and 13 candidate genes. The study found that the HS6ST1 gene is associated with body weight, body length, and total length, and may play a core role in muscle development and growth regulation (Figure 2) (Liu et al., 2024). The significant association between key traits (such as WT, TL, BL) and multiple chromosomal loci indicates the genetic diversity of this species in growth traits. This provides a powerful reference for subsequent molecular marker-assisted selection and breeding of superior strains in other species of the genus Channa.

Another study systematically evaluated the feasibility of genomic selection (GS) for the first time around two key growth traits of Channa maculata, weight and total length, and optimized the marker screening strategy in combination with genome-wide association analysis (GWAS) (Cui et al., 2024). A total of 790 individuals were subjected to SNP typing in the study, and 45 695 high-quality SNPs were screened for GS model construction, with estimated trait heritabilities of 0.32 and 0.30, respectively. Among the four GS models, BayesA and GBLUP performed well, especially when the 3K SNP panel screened by GWAS was used, the accuracy of weight prediction increased by up to 94.59%. The results of the study show that in the process of snakehead domestication, the integration of GWAS and GS can achieve efficient and low-cost genetic improvement of growth traits.

6.2 Research on the application of probiotics in Channa breeding

With the successful domestication of Channa sp., breeders have gradually incorporated it into the commercial breeding system. However, in the seedling stage, it often faces the problems of slow growth and low survival rate, which restricts the improvement of its breeding efficiency. Saputra et al. (2022) proved through experiments that adding probiotics to feed can effectively improve this problem. The study compared the effects of three probiotic combinations, among which the combination of Lactobacillus casei and Saccharomyces cerevisiae (P2) increased the survival rate of fish (86.67%), which was significantly higher than the control group (60.00%). At the same time, although the difference in growth parameters did not reach a significant level, the P2 group had the highest body length (4.67 mm) and weight gain (0.89 g). The water quality was always maintained within an appropriate range. The results of this study show that probiotics, as a green ecological breeding technology, can help improve fish health and production performance, and have practical value in promoting commercial breeding of local fish species.

7 Conservation Genetics and Germplasm Management in Channa

7.1 Genetic diversity maintenance in broodstock

In Channa farming, it’s really important to keep genetic diversity in the parent fish. This helps make sure the fish can survive in the long run and keeps farming sustainable. A study on Channa marulius found that the fish had a medium level of genetic diversity. But there was a problem-many fish had lower-than-expected heterozygosity. This means there might be inbreeding happening, or the group might have recently mixed with others in a way that affects the genes. Most of the genetic differences were found within individual fish, not between groups. So, managing parents properly is key. That includes avoiding inbreeding and keeping genetic variation high (Jabeen, 2022).

One way to do this is through rotational mating-changing which males and females breed each time. Another helpful method is freezing fish sperm or eggs (Liu et al., 2019). This process, called cryopreservation, lets us save genetic material for a long time. If needed, we can use it later to bring back lost diversity or help with breeding programs.

7.2 Policy and sustainable aquaculture implications

To make aquaculture more sustainable, we need to bring biodiversity protection into breeding plans. This means we shouldn’t just focus on farming more fish-we also need to protect their habitats and keep their genes from being lost. Good conservation work should include fixing natural habitats, doing artificial breeding, and saving genetic resources all at the same time (Liu et al., 2019).

Take Channa striata as an example. In breeding tanks, its gonads develop better when the setup is closer to nature. If the tank has a bottom layer of sediment about 15-20 cm deep, and 20% to 30% of the surface is covered by plants like water hyacinth (both floating and underwater ones), the fish do better. In one test, the average egg size reached 1.29 ± 0.21 mm. There were also a lot of mature eggs and sperm seen in the fish. This shows that habitat conditions, even in tanks, really matter for how well the fish can reproduce (Damle et al., 2023).

At the same time, routine genetic monitoring of seed populations can timely detect changes in genetic diversity and prevent the accumulation of harmful mutations. In the process of germplasm resource management and seed production, the introduction of evolutionary biology principles and quality management systems will improve the scientificity and effectiveness of long-term management of genetic resources.

8 Conclusions and Future Perspectives

In recent years, some progress has been made in the genome and transcriptome sequencing technology of the genus Channa, and a high-quality genetic resource library has been constructed, including annotated whole genomes and gene families related to key traits (such as hypoxia tolerance, growth and reproduction). These resources help screen candidate genes and molecular markers, provide support for selective breeding and artificial domestication, and thus cultivate improved strains with excellent performance and strong adaptability. The integration of genomic and transcriptome data, combined with marker-assisted selection (MAS) and genomic selection (GS) technology, provides an important opportunity to accelerate the genetic improvement of Channa. At the same time, technologies such as hormone-induced breeding domestication and probiotic feed addition have also shown good prospects in improving the growth, survival and reproductive performance of domesticated strains.

Although a large number of candidate genes and QTL loci for key traits have been identified, the specific functions of these genes in trait expression still need to be verified through experimental evidence. Current breeding strategies are still limited in accuracy, mainly due to the lack of conclusive data directly linking specific genetic variations to phenotypic outcomes. In addition, most studies are conducted in a single environment or laboratory conditions, which may not fully reflect the differences in the performance of traits under diversified breeding or natural conditions. Therefore, future research should strengthen multi-environment experiments and long-term monitoring to evaluate the stability and adaptability of traits, especially in the context of climate change and transformation of aquaculture models.

Future research should prioritize the development of integrated genomics-based breeding platforms, combining high-throughput genotyping, transcriptomics, and advanced selection models. These platforms will facilitate the rapid identification and deployment of superior genotypes, supporting both productivity and conservation goals. Given the increasing impact of climate change and disease threats, breeding programs should expand their focus to include the development of climate-resilient and disease-resistant Channa strains. This will require the identification and incorporation of novel alleles from wild populations, as well as the use of gene banks and ex situ reserves to safeguard genetic diversity for future improvement.

Acknowledgments

The authors sincerely thank Dr. Wang for reviewing the manuscript and providing valuable suggestions, which contributed to its improvement. Additionally, heartfelt gratitude is extended to the two anonymous peer reviewers for their comprehensive evaluation of the manuscript.

Conflict of Interest Disclosure

The authors affirm that this research was conducted without any commercial or financial relationships that could be construed as a potential conflict of interest.

Reference

Awal M.R., Pervin R., Rahman M.A., Bhadra A., Mahmud Y., Tanu M.B., and Parvez I., 2024, Effect of hormonal treatment on artificial propagation, spawning performance and embryonic development of striped snakehead Channa striata (Bloch, 1793), Animal Reproduction Science, 267: 107521.

https://doi.org/10.1016/j.anireprosci.2024.107521

Chandra R.K., Bhardwaj A.K., Pati A.K., and Tripathi M.K., 2023, Seasonal Immune Rhythms of head kidney and spleen cells in the freshwater Teleost, Channa punctatus, Fish and Shellfish Immunology Reports, 5: 100110.

https://doi.org/10.1016/j.fsirep.2023.100110

Cui T., Zhang J., Ou M., Luo Q., Fei S., Chen K., Zhao J., and Liu H., 2024, Potential of genome-wide association studies to improve genomic selection for growth traits in blotched snakehead (Channa maculata), Aquaculture, 580: 741895.

https://doi.org/10.1016/j.aquaculture.2024.741895

Cuomo A., Alvari G., Azodi C., McCarthy D., and Bonder M., 2021, Optimizing expression quantitative trait locus mapping workflows for single-cell studies, Genome Biology, 22: 188.

https://doi.org/10.1186/s13059-021-02407-x

Dewi C.D., Maulana U., El Rahimi S.A., and Ismarica I., 2023, Additional of EM4 and molasses in feeds on the growth and survival rate of snakehead (Channa striata), Depik, 12(1): 6-11.

https://doi.org/10.13170/depik.12.1.27330

Damle D., Kumar R., Ahilan B., Pillai B.R., Chidambaram P., Swain P.P., Debbarma J., and Sundaray J.K., 2023, The effect of habitat manipulation on early gonad maturation of Channa striata in captive condition, Indian Journal of Animal Research, 57(11): 1462-1468.

https://doi.org/10.18805/ijar.b-5177

Fan W., Zhang L., Su J., Luo Y., Jiao X., Huang Z., Zhao H., Zhao Z., Duan Y., Li Q., Du J., Zhuo T., Su Q., Wu J., and Zhou J., 2022, Genetic diversity of two color morphs of Northern snakehead (Channa argus) unveiled by the mitochondrial DNA D-loop region, Mitochondrial DNA Part B, 7(3): 515-520.

https://doi.org/10.1080/23802359.2022.2029601

Gamazon E., Wheeler H., Shah K., Mozaffari S., Aquino-Michaels K., Carroll R., Eyler A., Denny J., Nicolae D., Cox N., and Im H., 2015, A gene-based association method for mapping traits using reference transcriptome data, Nature Genetics, 47(9): 1091-1098.

https://doi.org/10.1038/ng.3367

Harrington L.A., Mookerjee A., Kalita M., Saikia A., Macdonald D.W., and D'Cruze N., 2022, Risks associated with the global demand for novel exotic pets: A new and emerging trade in snakehead fish (Channa spp.) from India, Biological Conservation, 265: 109377.

https://doi.org/10.1016/j.biocon.2021.109377

Hien T., Tâm B., Tu T., and Bengtson D., 2017, Weaning methods using formulated feeds for snakehead (Channa striata and Channa micropeltes) larvae, Aquaculture Research, 48(12): 4774-4782.

https://doi.org/10.1111/ARE.13298

Jabeen M., 2022, DNA markers based genetic polymorphism in natural populations of Channa marulius, Pakistan Journal of Zoology, 54(5): 2017-2024.

https://doi.org/10.17582/journal.pjz/20210812100840

Kumar R., Gokulakrishnan M., Debbarma J., and Damle D., 2022, Advances in captive breeding and seed rearing of striped murrel Channa striata, a high value food fish of Asia, Animal Reproduction Science, 238: 106957.

https://doi.org/10.1016/j.anireprosci.2022.106957

Li M., Liu X., Xia C., Wang G., and Zhang D., 2019, Astaxanthin enhances hematology, antioxidant and immunological parameters, immune-related gene expression, and disease resistance against in Channa argus, Aquaculture International, 27(2): 735-746.

https://doi.org/10.1007/s10499-019-00362-w

Liu H., Chen K., Luo Q., Ou M., Liu L., Gao D., Wu Y., Zhu X., and Zhao J., 2021, Construction of a high-density linkage map and QTL detection of growth and sex in blotched snakehead (Channa maculata), Aquaculture, 534: 736541.

https://doi.org/10.1016/J.AQUACULTURE.2021.736541

Liu H., Qing L., Ou M., Zhu X., Zhao J., and Chen K., 2020, High-density genetic linkage map and QTL fine mapping of growth and sex in snakehead (Channa argus), Aquaculture, 519: 734760.

https://doi.org/10.1016/j.aquaculture.2019.734760

Liu H., Xia W., Ou M., Luo Q., Zhang X., Fei S., Huang S., Zhao X., Zhang J., Cui T., Xiong B., Wu G., Chen K., and Zhao J., 2024, A genome-wide association study to identify growth-related SNPs and genes in blotched snakehead (Channa maculata), Aquaculture Reports, 29: 101932.

https://doi.org/10.1016/j.aqrep.2024.101932

Liu Y., Blackburn H., Taylor S., and Tiersch T., 2019, Development of germplasm repositories to assist conservation of endangered fishes: Examples from small-bodied livebearing fishes, Theriogenology, 135: 138-151.

https://doi.org/10.1016/J.THERIOGENOLOGY.2019.05.020

Luo Q., Ou M., Zhao J., Liu H., Gao D., Wu Y., Zhang L., and Chen K., 2020, Expression profile and estrogenic regulation of Amh during gonadal sex differentiation in northern snakehead (Channa argus), Genes & Genomics, 42(8): 827-835.

https://doi.org/10.1007/s13258-020-00943-7

Ma Z., and You X., 2021, Simulation analysis on genomic selection of grouper (Epinephelus coioides) breeding for categorical traits, Current Chinese Science, 1(1): 87-97.

https://doi.org/10.2174/2210298101999200909111243

Nagpal S., Meng X., Epstein M., Tsoi L., Patrick M., Gibson G., De Jager P., Bennett D., Wingo A., Wingo T., and Yang J., 2019, TIGAR: An improved Bayesian tool for transcriptomic data imputation enhances gene mapping of complex traits, American Journal of Human Genetics, 105(2): 258-266.

https://doi.org/10.1016/j.ajhg.2019.05.018

Ndobe S., Serdiati N., and Moore A.M., 2014, Domestication and length-weight relationship of striped snakehead Channa striata (Bloch), Proceeding of International Conference of Aquaculture Indonesia (ICAI) 2014, pp. 165-172.

https://doi.org/10.31230/osf.io/yv6ne

Nen P.H.A.N.N.A., Chheng P., So N., Hien T.T.T., Tam B.M., Egna H.I.L.L.A.R.Y., and Bengtson D.A., 2018, Performance of domesticated (Vietnamese) versus non-domesticated (Cambodian) snakehead, Channa striata (Bloch 1793) with regard to weaning onto pellet feed, Asian Fisheries Science, 31(3): 209-217.

https://doi.org/10.33997/j.afs.2018.31.3.003

Ou M., Chen K., Luo Q., Liu H., Wang Y., Chen B., Liang X., and Zhao J., 2021, Performance evaluation of XY all-male hybrids derived from XX female Channa argus and YY super-males Channa maculata, Aquaculture Reports, 20: 100768.

https://doi.org/10.1016/j.aqrep.2021.100768

Ou M., Yang C., Luo Q., Huang R., Zhang A., Liao L., Li Y., He L., Zhu Z., Chen K., and Wang Y., 2017, An NGS-based approach for the identification of sex-specific markers in snakehead (Channa argus), Oncotarget, 8(59): 98733-98744.

https://doi.org/10.18632/oncotarget.21924

Ou M., Zhao J., Qing L., Hong X., Zhu X., Liu H., and Chen K., 2018, Characteristics of hybrids derived from Channa argus ♀ × Channa maculata ♂, Aquaculture, 495: 248-256.

https://doi.org/10.1016/j.aquaculture.2018.04.038

Saputra F., and Ibrahim Y., 2021, Pengaruh komposisi probiotik yang berbeda pada pakan buatan terhadap rasio konversi pakan dan laju pertumbuhan benih ikan gabus lokal (channa sp.) hasil domestikasi, Jurnal Perikanan Tropis, 8(1): 1-9.

https://jurnal.unimal.ac.id/jpt/article/view/4762

Saputra F., and Mahendra M., 2019, Maintenance of local snakehead postlarva Channa sp. on different containers in domestication framework, Jurnal Iktiologi Indonesia, 19(2): 139-144.

https://doi.org/10.32491/jii.v19i2.477

Saputra F., Ibrahim Y., Islama D., Mahendra M., Nasution M.A., and Khairi I., 2022, Pemberian probiotik untuk optimalisasi kelangsungan hidup dan pertumbuhan ikan gabus lokal (Channa sp.) hasil domestikasi, Jurnal Perikanan Tropis, 9(1): 37-46.

https://doi.org/10.35308/jpt.v9i1.6014

Sodsuk P., 2012, Allozyme-based analysis of genetic variation among 3 cultured stocks of snakehead fish, Channa striata (Bloch, 1797), The Thai Journal of Genetics, 5(2): 183-193.

https://doi.org/10.14456/tjg.2012.12

Sun D., Wen H., Qi X., Li C., Sun C., Wang L., Zhu M., Jiang T., Zhang X., and Li Y., 2023, Comparative study of candidate sex determination regions in snakeheads (Channa argus and C. maculata) and development of novel sex markers, Aquaculture, 575: 739771.

https://doi.org/10.1016/j.aquaculture.2023.739771

Verma V., Rani K., Sehgal N., and Prakash O., 2015, Enhanced disease resistance in the Indian snakehead, Channa punctata against Aeromonas hydrophila, through 5% feed supplementation with F. benghalensis (aerial root) and L. leucocephala (pod seed), Aquaculture International, 23(4): 1127-1140.

https://doi.org/10.1007/s10499-014-9870-7

Wakiah A., Mallawa A., and Amir F., 2020, Population dynamics of snakehead fish (Channa striata) in the Lake Tempe, South Sulawesi, Indonesia, AACL Bioflux, 13(5): 3015-3027.

Wang D.D., Zhang G.R., Wei K.J., Ji W., Gardner J.P., Yang R.B., and Chen K.C., 2015, Molecular identification and expression of the Foxl2 gene during gonadal sex differentiation in northern snakehead Channa argus, Fish Physiology and Biochemistry, 41(6): 1419-1433.

https://doi.org/10.1007/s10695-015-0096-z

Yan R.J., Zhang G.R., Guo X.B., Ji W., Chen K.C., Zou G.W., Wei K., and Gardner J., 2018, Genetic diversity and population structure of the northern snakehead (Channa argus Channidae: Teleostei) in central China: implications for conservation and management, Conservation Genetics, 19(2): 467-480.

https://doi.org/10.1007/s10592-017-1023-x

Zhao J., Ou M., Wang Y., Liu H., Luo Q., Zhu X., Chen B., and Chen K., 2021, Breeding of YY super-male of blotched snakehead (Channa maculata) and production of all-male hybrid (Channa argus ♀ × C. maculata ♂), Aquaculture, 538: 736450.

https://doi.org/10.1016/j.aquaculture.2021.736450