In this study, we conducted an exploration of blood collection, hematological and biochemical comparative analysis of the unique vitreous humor and blood of the celestial-eye goldfish (CE) (Carassius auratus), and obtained hematological and biochemical indicators for healthy celestial goldfish blood. After exploring the optimal method for collecting blood and ocular fluid, blood and vitreous humor samples were drawn from healthy CE, and an automatic hematology analyzer was used to measure 17 physiological indicators in the blood and vitreous humor. Additionally, 20 biochemical indices were measured by an automatic biochemical analyzer. Experiments were also conductedto evaluate the effect of blood and vitreous humor collection on the subsequent survival rate of the CE. The results showed that the blood of CE exhibited values for 17 hematological indicators, including red blood cells (mean value: 2.19 × 1012/L), white blood cells (mean value: 62.21 × 109/L), hemoglobin (mean value:138.25 g/L), and no eosinophils or basophils. We also found that the levels of aspartate amino transferase (AST) and glutamyl transpeptidase (GGT) in the vitreous humor of CE were significantly higher than those in the serum (p < 0.01). No cells were detected in the vitreous humor of CE, and there was no significant difference in survival rate compared to normal goldfish after extracting blood and vitreous humor from CE (p > 0.05). This study provides fundamental data for the cultivation of healthy goldfish, the development of goldfish hematology, and further research on the development and formation of CE’s unique eye traits.

While short-term faba bean feeding is known to improve fish texture, its long-term systemic effects and the underlying molecular mechanisms in Nile tilapia remain rarely explored. This knowledge gap is critical, given the potential for extended feeding to induce distinct metabolic reprogramming and trade-offs. Here, we present the first comprehensive study investigating the 180-day impact of a 60% FB-based diet (FBD) on Nile tilapia through an integrated analysis of phenotypic traits, muscle histology, metabolome, and transcriptome. Our results revealed a fundamental trade-off: FBD feeding induced hyperplasia-driven muscle remodeling, significantly enhancing textural properties (hardness, gumminess, chewiness) and increasing intramuscular fat and collagen content, but at the cost of suppressed growth and hepatosomatic index. Metabolomics identified 243 significantly altered metabolites, outlining a systemic metabolic shift characterized by activated lipid synthesis but inhibited amino acid and energy metabolism. This multi-omics integration nominated the chac1 gene as a novel key regulator for FB-induced muscle hyperplasia, a finding not previously reported in this context. We propose a mechanistic model wherein long-term FBD feeding coordinates lipid deposition, collagen accumulation, and chac1-mediated hyperplastic growth to remodel muscle texture. Our work provides new insights into the long-term metabolic trade-offs and molecular drivers of FB-induced flesh quality improvement, offering a theoretical foundation for developing optimized aquafeeds.

Goldfish (Carassius auratus), subjected to millennia of artificial selection and breeding, have diversified into numerous ornamental varieties, such as the celestial-eye (CE) goldfish, noted for its unique dorsal eye rotation. Previous studies have primarily focused on anatomical modifications in CE goldfish eyes, yet the molecular underpinnings of their distinctive eye orientation remain poorly understood. This study employed high-throughput transcriptome and proteome sequencing on 110-day-old full-sibling CE goldfish, which displayed either anterior or upward eye rotations. Verification of these findings was conducted using quantitative PCR (qPCR) for transcriptomic data and parallel reaction monitoring (PRM) for proteomic analysis. Our research identified 73,685 genes and 7717 proteins, pinpointing 8 common differentially expressed genes (DEGs) and proteins (DEPs) implicated in cytoskeleton remodeling, cell adhesion, apoptosis, and optic nerve regeneration. Enrichment analyses further delineated pathways associated with apoptosis, necroptosis, and cell adhesion molecules. The results indicated a significant role for genes involved in cytoskeletal dynamics, nervous system function, and apoptotic processes in the dorsal eye rotation of CE goldfish. Analyses of abnormalities in ocular membrane structures, along with disturbances in lipid and protein synthesis metabolism and energy metabolism during developmental stages, provided compelling evidence for the potential use of CE goldfish as a model organism in studying human eye-related disorders. This investigation provided the first comprehensive transcriptomic and proteomic overview of eye rotation in CE goldfish, offering insights crucial for the genetic breeding of new ornamental fish varieties.

After intensive artificial selection, the development of celestial eyes in goldfish involves the eyeballs protuberating and turning upwards. Thus, the celestial eye goldfish is an excellent model for both evolutionary and human ocular disease studies. Here, two mapping populations of goldfish with segregating eye phenotypes in the offspring were constructed. Through whole-genome sequencing and RNA-seq for eyeball samples, a premature stop codon in Exon 38 of the LRP2 gene was identified as the top candidate mutation for the celestial eye in goldfish. Fatty acid metabolism and epidermal cells, especially keratocyte-related functions, were inhibited in the eyeballs of celestial eye goldfish, while inflammatory reactions and extracellular matrix secretions were stimulated. These results suggest the dysfunction of the cornea in the celestial eye goldfish, and the same for the retina, which could be the results of the truncated LRP2 protein. In addition, the same gene, LRP2, is in charge of similar phenotypes (celestial eye and telescope eye) in goldfish, but these phenotypes have no shared mutations. In conclusion, the candidate mutation for the celestial eye in goldfish was identified by this study for the first time, and parallel evolutions of similar phenotypes at the molecular level under artificial selection were observed. These findings provide insights into the developmental and evolutionary processes of morphological changes in the eyes of goldfish.

After the intensive artificial selection, the development of celestial-eye in goldfish involves the protuberating and turning upwards of eyeballs, and also degeneration of the retinal. Thus, the celestial-eye goldfish provides an excellent model for both evolutionary and human ocular disease studies. Here, two mapping populations with segregating eye phenotypes in the offspring goldfish were constructed. Though whole genome sequencing using individual samples from the parents and pooled samples from the offspring, and RNA-seq for eyeball samples from pure goldfish lines, a premature stop codon in Exon 38 of  LRP2 gene was identified as the top candidate mutation that is responsible for celestial-eye in goldfish. Fatty acid metabolisms and epidermal cells, especially keratocytes related functions were inhibited in the eyeballs of celestial-eye, while inflammatory reactions and extracellular matrix secreting were stimulated. These suggest the dysfunction of cornea in the celestial-eye, and same for retinal, which could be the results of the truncated LRP2 protein. Besides, evidence was provided that not all the goldfish lines share the same causal mutation for celestial-eye, while the same gene LRP2 is in charge of the similar phenotypes (celestial-eye and telescope-eye) in goldfish but no shared mutation. Therefore, those mutations and the associated phenotypes exhibit parallel evolutions in molecular level under artificial selections. Overall, the candidate mutation for celestial-eye in goldfish was identified by this study, and further analyses provide insights into the developmental and evolutionary processes of morphological changes in the eyes of goldfish. ### Competing Interest Statement The authors have declared no competing interest.

This study layed the groundwork for the creation of haploid and triploid celestial goldfish, presenting essential data derived from preliminary investigations. The research delved into three main areas: the short-term preservation of celestial goldfish gametes, the interaction between oocytes and foreign sperm, and the effects of temperature on fertilized eggs concerning hatching rates and late-stage ocular development. Initially, the study explored the optimal semen dilution ratio for celestial goldfish under microscopic examination. And the hybridization of the largemouth bass and celestial goldfish was investigated: largemouth bass sperm was crossbred with celestial goldfish eggs, and it was found that their sperm could not stimulate the development of celestial eye eggs. At last, celestial goldfish fertilized eggs were stimulated at 4 °C and −20 °C, respectively, to observe their impact on the hatching rate and later celestial eye rate. The results revealed no significant differences in hatching rate and celestial eye rate between the cold stimulus groups and the control group, but numerically, the 4 °C cold stimulation reduced the celestial eye rate of celestial goldfish fertilized eggs. The research provided fundamental data for artificial breeding and hybridization experiments in celestial goldfish.

The transcriptomes of skin were sequenced in two types of monochromatic red common carp（Cyprinus carpio） with body length of（33.42 ±0.24） cm and yellow common carp with body length of（38.75±0.43） cm using Illumina Hi-seq sequencing technology, and differentially expressed genes were identified and selected for analysis in order to investigate the genetic resources of whole red and yellow common carp. The results showed that 129 222 850 clean reads were obtained in whole red and 130 869 572 in whole yellow common carp. Comparison with known genes 58 782 genes were annotated in the Nr, 61 490 in Nt, 11 468 in COG, 31 206 in GO, 31 581 in KEGG, 61 385 in Pfam and 51 805 in Uniprot databases, with 8 378 genes annotated in all seven databases. There were 4 822 differentially expressed genes in skins of whole red and yellow common carp, with 1 929 significantly up-regulated and 2 893 significantly down-regulated. Further clustering analysis of differentially expressed genes revealed similar patterns of high and low expression of differentially expressed genes in both skin samples. The reliability of transcriptome data results was confirmed by qRT-PCR validation of 9 differentially expressed genes, in which some genes found here were involved in body color regulation, such as mitfa, ednrA, wnt7, agouti and mif. KEGG analysis revealed that differential genes were significantly enriched in 43 pathways, including mannose and fructose metabolism, glycolysis/gluconeogenesis, carbon metabolism, pentose phosphate pathway and tyrosine metabolism. The analysis of tyrosine metabolism and melanin synthesis pathways showed that mif, mif4g, agouti, ednrA and ednrB were significantly upregulated and tyr, tyrp1, mitfa and wnt7 were significantly downregulated in genes related to red and yellow pigment synthesis. Analysis of differential genetic variation indicated a total of 388 673 single nucleotide polymorphism（SNP） markers in both whole red and whole yellow common carp. The findings indicated that the differentially expressed genes in the skin tissues of two monochromatic common carp were primarily enriched in energy metabolism, growth, and immunity pathways. The transcriptome data obtained can be used to develop molecular markers as well as cloning, editing, and functional analysis of functional genes in koi.

我国是新烟碱类杀虫剂生产、销售和使用大国,噻虫嗪等新烟碱类农药在水环境中检出率较高.本文以本土物种稀有鮈鲫为研究对象,开展胚胎及幼鱼噻虫嗪(005、5和50 μg·L-1)半静态暴露实验,评估药物对稀有鮈鲫早期生命阶段毒性效应.结果表明,50pg-L-1噻虫嗪暴露可导致稀有鮈鲫胚胎死亡率显著增加,药物处理组孵化后仔鱼畸形率均显著增加,仔鱼畸形多呈现为脊柱弯曲.28 d幼鱼亚慢性暴露实验结果表明,不同梯度噻虫嗪暴露均可导致幼鱼死亡率增加;功能基因定量结果显示稀有鮈鲫幼鱼胆固醇合成相关基因sc5d、ebp和sc4mol在转录水平表达下调,nsdh1、caspase3和ctslla与对照组相比无显著性差异.5μg·L-1噻虫嗪处理组中幼鱼p53、p21和mycb等基因转录水平表达显著下调.上述结果表明,新烟碱类杀虫剂噻虫嗪对稀有鮈鲫早期生命阶段存在胚胎毒性,并导致仔鱼致畸和死亡;功能基因转录水平变化预示药物暴露可能增加幼鱼致癌风险,这些可能对鱼类种群繁衍产生负面效应.

Skin color is an important phenotypic feature of vertebrate fitness under natural conditions. Celestial goldfish, a common goldfish breed in China, mainly shows three kinds of skin colors including white, yellow and brown. However, the molecular genetic basis of this phenotype is still unclear. In this study, high-throughput sequencing was carried out on the back skin tissues of celestial goldfish with different skin colors. About 58.46 Gb of original data were generated, filtered and blasted, and 74,297 mRNAs were obtained according to the reference transcriptome. A total of 4653 differentially expressed genes were screened out among the brown, yellow and white groups, and the expression of melanogenesis related genes in brown goldfish was significantly higher than the other two groups. There are 19 common differentially expressed genes among three groups, of which eight genes are related to pigment production, including tyrp1a, slc2a11b, mlana, gch2, loc113060382, loc113079820, loc113068772 and loc113059134. RT-qPCR verified that the expression patterns of randomly selected differentially expressed transcripts were highly consistent with those obtained by RNA sequencing. GO and KEGG annotation revealed that these differentially expressed genes were mostly enriched in pathways of the production of pigment, including melanogenesis, tyrosine metabolism, Wnt signaling pathway, MAPK signaling pathway etc. These results indicated that the external characteristics of goldfish are consistent with the analysis results at transcriptome level. The results of this study will lay a foundation for further study on the expression characteristics and gene network analysis of pigment related genes.

为探究CYP17a1基因在锦鲤(Cyprinus carpio)性腺不同发育时期的作用及其在不同组织中的表达水平,采用实时荧光定量PCR和蛋白质免疫印迹(Western blot)技术,分析了细胞色素CYP17a1基因在1～3龄锦鲤成鱼性腺发育6个时期(Ⅰ期、Ⅱ期、Ⅲ期、Ⅳ期、V期、Ⅵ期),及精巢(卵巢)、脑、肌肉和肾脏等不同组织中CYP17a1 mRNA和蛋白质的表达情况.结果显示,1～3龄锦鲤雌鱼、雄鱼性腺发育不同时期成熟系数(GSI)变化规律基本相同,其中3龄锦鲤性腺V期时最高,但卵巢GSI明显高于精巢.CYP17a1 mRNA在卵巢、精巢、脑、肌肉和肾脏都有表达,各组织表达量存在显著差异(P＜0.05),表现为精巢＞卵巢＞肌肉＞肾脏＞脑,卵巢、精巢的表达量随着年龄增加有升高趋势,在脑、肌肉和肾脏中无明显年龄差别.CYP17a1基因在1～3龄锦鲤卵巢、精巢的6个不同发育时期表达量均值呈现先降低后升高趋势,并呈现出随年龄增长,表达量显著升高的现象.3龄锦鲤精巢Ⅰ期表达量最高,是同龄锦鲤精巢Ⅲ期和Ⅳ期表达量的2.75倍和3.13倍.Western blot检测结果显示,CYP17a1蛋白表达水平与mRNA表达水平一致.以上研究结果表明,细胞色素CYP17a1基因在锦鲤性腺发育中发挥着一定作用,可能在精巢发育及精子细胞分化成熟方面具有重要促进作用.

为了探索红望天眼金鱼Carassius auratus的变色机制,采用RNA-Seq高通量测序技术,对红望天眼金鱼(145日龄,体长6 cm)由灰色、过渡色到橙红色3个变色阶段进行了转录组学分析.结果表明:共得到过滤后碱基量57.8 Gb,构建了新转录本并预测新基因1629个,在两两组比较的差异表达基因群中分析出3个变色组共有差异表达基因25个;差异表达基因的GO功能富集和KEGG通路富集分析显示,差异基因主要富集到免疫反应、细胞增殖与凋亡和黑色素等相关通路;根据转录组比较分析结果和实际生产经验观察积累,初步推测红望天眼金鱼变色的生理机制是红望天眼金鱼变色初期黑色素细胞大量增殖,期间发生免疫炎症反应,随后黑色素细胞开始逐渐凋亡,同时其他色素细胞则逐渐增殖分化,直至完全取代黑色素细胞,完成变色过程.本研究初步分析出了红望天眼金鱼的皮肤变色机制,研究结果可为进一步开展调控金鱼变色的功能基因试验和金鱼变色的分子机理研究提供科学参考.

试验旨在探索研究不同的水深和容器的透光性是否影响望天眼金鱼最终成功翻眼率,并通过杂交试验,探讨金鱼望天眼性状是否稳定遗传.试验首先选取红望天眼金鱼两雌一雄和一雄偏龙睛五花金鱼,进行人工混合繁殖,随机选取后代分四组,分别在透明玻璃缸水深15 cm(A)、透明玻璃缸水深30 cm(B)、不透光塑缸水深15 cm(C)和不透光塑缸水深30 cm(D)环境中养殖290 d,统计最终金鱼成功翻眼率,进行双因素方差分析,同时进行望天眼金鱼与翻眼不成功的介于望天和龙睛中间体的金鱼进行正反交和各自自交,统计后代最终的眼睛性状.结果显示:水深对望天眼金鱼成功翻眼率影响极显著,容器透光性对其影响不显著;亲本翻眼程度越大,其后代望天比例越高,表明望天眼性状受遗传影响较大,并且一定程度上受母体遗传效应影响.

为研究复合益生菌对大口黑鲈Micropterus salmoides延后繁殖性能、生理指标及仔鱼成活率的影响,试验选取150组亲鱼(雌、雄鱼体质量分别为550～665、500～573 g),随机分成5组,每组设3个平行,分别在基础饲料中添加0、0.1％、0.3％、0.5％、0.7％(均为质量分数,下同)复合益生菌制剂,养殖周期为30 d.结果表明:雌鱼的性腺指数、怀卵量、相对怀卵量随饲料中复合益生菌添加量的增加逐渐增大,并于0.5％添加量时达到峰值,但这3个指标在各组间均无显著性差异(P>0.05);0.3％、0.5％复合益生菌添加组第一批产卵量、受精率、孵化率、仔鱼成活率均高于其他组,其中,仅0.5％添加组仔鱼成活率显著高于对照组和0.1％添加组(P<0.05);产卵前,不同试验组雌鱼肝脏中AKP、ACP活力均显著高于产卵后(P<0.05),且2种酶活力均随饲料中复合益生菌添加量的增加逐渐增强,当添加量为0.5％时2种酶活力均达到峰值,产卵前不同添加组雌鱼肝脏中T-SOD活力无显著性差异(P>0.05),0.3％、0.5％添加组雌鱼血浆中T-SOD活力显著高于其他组(P<0.05).研究表明,复合益生菌添加量为0.5％时,复合益生菌饲料可显著提高大口黑鲈仔鱼成活率,增强产卵前雌鱼肝脏中AKP、ACP活力及血浆中T-SOD活力,本研究结果可为复合益生菌在大口黑鲈延后繁育工作中的应用提供科学参考.

为探究罗非鱼养殖密度对养殖水体水质参数及菌群多样性的影响,开展30 d养殖密度试验.通过水质监测和组织病理学检测,结合Illumina Miseq进行养殖水体细菌16S rDNA高通量测序,分析养殖密度、水质参数与菌群多样性三者相关性.结果表明,养殖密度对肝脏组织无显著影响,但随养殖密度增加罗非鱼鳃小叶变形扭曲、部分末端膨大甚至脱落.养殖水体中溶解氧含量随养殖密度增加而降低(P<0.05),氨氮、亚硝酸盐氮和硝酸盐氮等无机氮类含量呈阶段性变化.水质参数相关系数矩阵及载荷分析结果显示,不同养殖密度组水体硝酸盐氮和亚硝酸盐氮均为中等强度相关;低密度和高密度组溶解氧与氨氮呈负中等强度相关,中密度组中溶解氧与氨氮呈负极强相关.不同养殖密度水体中菌群丰度存在差异,优势菌属为黄杆菌属、新鞘脂菌属、hgcl clade、大单胞菌属等多具备污染物降解能力的细菌.上述结果表明,罗非鱼中等养殖密度下保证足够的供氧量可促进水体中无机氮的降解,结合有效的水处理可保证鱼类生长,将能带来最大化的经济效应.

为了获得红白锦鲤的基因组信息,筛选与其肤色相关的基因,采用Illumina高通量测序技术对红白锦鲤皮肤组织的基因组进行测序,获得127.23 Gb clean data,Q20碱基比例在95.59％及以上,Q30碱基比例在90.81％及以上,GC含量为37.32％ ～ 42.38％,测序错误率为0.07.与鲤鱼基因组序列进行比对的结果显示,比对效率为96.35％.研究共鉴定了1 048 576个SNPs(单核苷酸多态性),其中3.12百万～5.40百万个SNPs位于短reads比对不到的区域,其中变异位点位于外显子区域的有579 778个SNPs.SNP位点分布于锦鲤的50条染色体上,不包含scaffold(染色体骨架).经ANNOVAR软件进行功能注释,纯合类型的SNPs数量是574 310个,杂合类型的SNPs数量是474 265个.SNPs位于基因间的数量最多,SNPs位于基因内的外显子区域的多态性最高.通过对8个重要候选基因注释的理解,发现微管蛋白LOC109046532、LOC109049213这2个基因与色素颗粒运输有关.其中基因LOC109046532含有突变,而另1个基因LOC109049213则不含有任何突变.8个候选基因都含有外显子SNP位点,但是没有发现终止密码子突变.

A total of 336 individuals of common carp Cyprinus carpio with an initial body weight of (73.66±0.21) g were randomly divided into 8 groups with 3 replicates per group, 14 fish per replicates, reared in an indoor tank of 100 cm×50 cm×50 cm and fed basal diet( control group A) , and the basal diets supplemented with sun-dried vermicompost, whose nutritional level and safety were evaluated, at a rate of 2.5%(group B1) , 5.0%(group B2), and 7.5%( group B3) , and with high-temperature dried vermicompost at a rate of 5.0%( group C1) , and 7.5% ( group C2) , and with mixture of sun-dried vermicompost and earthworm powder at a ratio of 5.0%+0.15%(group D1) , and 7.5%+0.23%(group D2) at water temperature of 27-29 ℃ for 60 d. The growth performance digestive enzyme activity and antioxidant indices in serum and hepatopancreas ofcommon carp were determined at the end of the experiment. The results showed that the contents of heavy metals in the common carp fed the diets containing vermicompost were well under the level of hygienical standard for feeds, and the different levels of additional vermi-compost showed certain effects on the weight gain rate, specific growth rate, serum and antioxidative indices in ser-um and hepatopancreas, significant differences in superoxid dismutase activity between the treatment groups and the control group( P<0.05) except for B1 group. There was no significant difference in food conversion ratio and activi-ties of intestinal digestive enzymes among the fish fed the diets containing different levels of vermicompost ( P>0.05) . The findings provided theoretical reference and data for reasonable application and development of vermi-compost as feed additives in aquaculture.

以初始体质量约为(132.4±4.6)g的锦鲤为对象,研究不同氨氮浓度对锦鲤肝脏超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、乙酰胆碱酯酶(AChE)活性与抗氧化酶基因(AchE、Cyp450)、皮肤体色基因(Tyr、Mc1r)表达的影响.结果表明,氨氮对锦鲤在24、48、72、96 h的半致死浓度(LC50)分别为51.34、42.53、31.18、27.29 mg/L,安全浓度为2.73 mg/L.氨氮暴露初期(2 d),各试验组总SOD活性无显著差异,暴露中后期(6、10、14 d),各试验组总SOD活性整体上表现出先升高后降低的趋势;在氨氮胁迫下,各试验组CAT、AChE活性分别大致呈现先增加后降低、一直降低的趋势;锦鲤肝脏组织中AchE基因表达量与对照相比显著下降(P<0.05);Cyp450基因在暴露初期(2 d)和中期(6 d)无明显变化,而在暴露中后期(10、14 d)表达量明显下调(P<0.05);皮肤体色基因Tyr、Mc1r的表达量在氨氮暴露后均明显受到抑制.可以得出,随着氨氮暴露浓度的增加和暴露时间的延长,锦鲤免疫酶活性和基因表达量均趋于降低,说明鱼体免疫防御系统遭到了损伤.

Illumina PE150 high－throughput sequencing technology was used to sequence the transcriptome of white skin and red skin tissue of Cyprinus carpio haematopterus with body length of (28.34±3.12) cm in order to further develop gene resources of red and white koi carp Cyprinus carpio haematopterus. The 116. 26 Gb Clean Date ob-tained were compared with seven databases of Nr, GO, KEGG, KOG, Pfam, Swiss－Prot, and eggNOG. A total of 10 476 annotated genes were obtained, with the maxiaml percent of annotation success(35.62%) in Nr database. The functional and pathway enrichment analysis revealed that differential genes were enriched in 132 metabolic pathways including regulation of actin cytoskeleton and focal adhesion pathway. qRT－PCR of 9 differentially ex-pressed genes selected randomly showed that the expression of differentially expressed genes in the skin of Cyprinus carpio haematopterus was consistent with the quantitative results of RNA－seq, indicating that the transcriptome se-quencing were reliable. The transcriptome data obtained in this study can provide basic data for future research on key gene development and functional analysis of ornamental fish skin color.

The study of codon usage bias in species can be in-depth understanding of gene expressions,and provide the basis for molecular breeding.8 143 eligible coding DNA sequences were selecting from transcriptome data of Carassius auratus which were obtained through transcriptome sequencing by Illumina HiSeq 2000.CDS were analyzed by CodonW and CUSP programs in C.auratus genome,calculating frequency of codon usage which enco-ded amino acids and comparing with variety classes of mode organisms such as:Homo sapiens,yeast,E.coli,Dro-sophila,D.rerio. The consequences indicated that twenty-eight optimal codons of C.auratus were identified in 64 codons,effective number of codons was 54.9,GC content of genes was 0.509,GC content at the third position of synonymous codon was 0.564 the codons which were ending with G or C were bias using. And codon bias of C.auratuswas difference in various degrees with other mode organisms,codon usage frequency of C.auratus was big-gest different from yeast,but had a consistency with codon bias of D.rerio.