The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid group...The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid grouper juveniles(9.39 ± 0.07 g) were investigated under the fed and un-fed conditions. The results showed that the OCR and AER were significantly(P < 0.05) affected by temperature and salinity under both fed and un-fed conditions. When temperature was 24–33℃, the OCR and AER of fed hybrid grouper juveniles were 85.68%–129.52% and 125.78%–287.63%, respectively, higher than those of un-fed hybrid grouper juveniles. The O/N ratio, protein use(P_u), Q_(10)(respiration) and Q_(10)(excretion) of fed hybrid grouper juveniles were 14.43–24.01, 28.35% – 48.48%, 1.69 and 3.01, respectively. The O/N ratio, P_u, Q_(10)(respiration), Q_(10)(excretion) of un-fed hybrid grouper juveniles were 20.39 – 31.79, 22.16% – 34.34%, 1.23 and 1.17, respectively. When salinity was 15–33, the OCR and AER of fed hybrid grouper juveniles increased by 87.42% – 116.85% and 215.38% – 353.57%, respectively, over those of un-fed hybrid grouper juveniles. The O/N ratio and P_u of fed hybrid grouper juveniles were 14.48 – 17.78, 39.36% – 49.43%, respectively. The O/N ratio and Pu of un-fed hybrid grouper juveniles were 20.39 – 31.79 and 22.16% – 34.34%, respectively. The specific dynamic action(SDA) of hybrid grouper juveniles was mainly related to protein metabolism. The results had a guiding significance to the large-scale intensive aquaculture of hybrid grouper juveniles.展开更多
The effects of temperature and pH on embryonic development and survival rate of newly hatched larvae of Epinephelus fuscoguttatus were discussed by single factor experiment method. Under a salinity of 31‰, fertilized...The effects of temperature and pH on embryonic development and survival rate of newly hatched larvae of Epinephelus fuscoguttatus were discussed by single factor experiment method. Under a salinity of 31‰, fertilized eggs were incubated at different temperatures (17, 20, 23, 26, 29 (eontrol), 32, 35 ℃ ) and different pH values (5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.4 (control), 8.5, 9.0, 9.5 and 10.0), the development rate of fertilized eggs, hatching rate, deformity rate, survival rate of newly hatched larvae, and optimum temperature and pH ranges for embryonic development were recorded and analyzed. The results showed that the incubation period y required by fertilized eggs was in remarkably negative correlation with temperature x, y =4 017. 3x-15277 , R2 =0. 971 3. At 29 ℃, the hatching rate was the highest, up to 92.00% ; this temperature was corresponding to the lowest deformity rate of newly hatched larvae ( 1.09% ) ; corresponding effective accumulative temperature was also the lowest (437. 410 ℃ . h), and significantly different from other experimental groups (P 〈 0.05 ) ; but on the contrary, corresponding survival rates at 24 and 48 h reached, respectively, 88.03% and 82. 97% which were significantly different from other experimental groups ( P 〈 0.05). At the pH of 8.4 in the CK group and the pH of 8.5 of one experimental group, the embryonic development rates were the highest; con-esponding hatching rates of fertilized eggs were the highest, respectively, of 88.33% and 83.33% which were significantly different from other groups (P 〈 0.05) ; and corresponding survival rates at 24 and 48 h were the highest, and reached 90.84% and 85.03%, respectively. In the pH range of 8.0 - 8.5, the deformity rate of newly hatched larvae was 0. It was indicating that for embryonic development of E. fuscoguttatus, the suitable water temperature value was in the range of 17 - 29 ℃, the optimum value was in the range of 23 -29℃; and the suitable pH value was in the range of 6.5 -9.5, and the optimum value was in the range of 8.0- 8.5.展开更多
The present study was conducted as a continuation of our previous study on the effects of fish meal replacement with soy bean meal, SBM in the diets of tiger grouper, Epinephelus fuscoguttatus which revealed the possi...The present study was conducted as a continuation of our previous study on the effects of fish meal replacement with soy bean meal, SBM in the diets of tiger grouper, Epinephelus fuscoguttatus which revealed the possible level of fish meal protein replacement of 30% with positive effect of phytase supplementation in one of the test diet. In the present study, all experimental diets with SBM inclusion (10%, 20%, 30%, 40% replacement levels) were supplemented with phytase and fed to juvenile tiger grouper with initial body weight of 44.57 ± 0.28 g for eight weeks. Apart from the effects on growth performance, diet utilization and fish whole-body composition, apparent digestibility coefficient of diets was also measured. Similar findings to our previous experiment were observed in the present study. Diet SM40P (40% replacement level) had produced the poorest growth performance and feed conversion ratio (FCR). However, it was observed that FCR of SM40P was improved when compared to SM40 (without phytase) in our previous experiment. Other than that, SBM-based diets were performed as good as the control diet in terms of growth, feed utilization and survival rate. Replacement of fish meal did not significantly influence body composition, except for whole body lipid content in SM40P. In general, dry matter and protein apparent digestibility coefficients (ADC) of the test diets were influenced by SBM inclusion in the diets. However, crude lipid ADC was very high in all dietary treatments indicating efficient utilization of dietary lipid by juvenile tiger grouper. The findings of the present study confirmed that SBM can be used to replace FM at a level of up to 30% and supplementation of phytase in SBM-based diets is recommended to improve the diet performance.展开更多
The effects of fish meal (FM) replacement with graded level of soybean meal (SBM) on growth performance, feed utilization, survival rate and body composition were investigated in juvenile tiger grouper, Epinephelus fu...The effects of fish meal (FM) replacement with graded level of soybean meal (SBM) on growth performance, feed utilization, survival rate and body composition were investigated in juvenile tiger grouper, Epinephelus fuscoguttatus (initial body weight 13.9 ±0.65 g). Six experimental diets were formulated to contain 50% crude protein, 16% crude lipid and 365.8 kcal/100g feed with SBM replacing FM protein at 0% (SM 0), 10% (SM 0), 20% (SM 20), 30% (SM 30), 40% (SM 40) and 20% with phytase (SM 20P) replacement levels. At the end of the ten-week feeding trial, there were no significant differences detected in terms of growth performances (weight gain and specific growth rate), feed conversion ratio (FCR) and survival rates of fish fed with the control diet (SM 0), SM 20, SM 30 and SM 20P. Net protein utilization of fish fed SM 20P was higher than those fed with other diets suggesting an improved utilization of nutrients with phytase addition in the diet. Replacements of FM protein with SBM at 10% and 40% have resulted in significantly lower growth and poorer FCR than other replacement levels. Survival rates remain high (≥90%) throughout the trial. Whole-body proximate composition of the fish was significantly affected by the inclusion of SBM in the diets. It can be concluded that 20%-30% of FM protein replacement with SBM is recommended and addition of phytase in the SBM-based diet should be considered to improve nutrient utilization of tiger grouper juvenile.展开更多
The mitochondrial genome(mitogenome)of hybrid grouper Epinephelus moara(♀)×Epinephelus tukula(♂),a new hybrid progeny,can provide valuable information for analyzing phylogeny and molecular evolution.In this stu...The mitochondrial genome(mitogenome)of hybrid grouper Epinephelus moara(♀)×Epinephelus tukula(♂),a new hybrid progeny,can provide valuable information for analyzing phylogeny and molecular evolution.In this study,the mitogenome was analyzed using PCR amplification and sequenced,then the phylogenetic relationship of E.moara(♀)×E.tukula(♂)and 35 other species were constructed using Maximum Likelihood and NeighborJoining methods with the nucleotide sequences of 13 conserved protein-coding genes(PCGs).The complete mitogenome of E.moara(♀)×E.tukula(♂)was 16695 bp in length,which contained 13 PCGs,2 rRNA genes,22 tRNA genes,a replication origin and a control region.The composition and order of these genes were consistent with most other vertebrates.Of the 13 PCGs,12 PCGs were encoded on the heavy strand,and ND6 was encoded on the light strand.The mitogenome of the E.moara(♀)×E.tukula(♂)had a higher AT nucleotide content,a positive AT-skew and a negative GC-skew.All protein initiation codons were ATG,except for COX and ND4(GTG),ATP6(CTG),and ND3(ATA).ND2,COXII,ND3,ND4 and Cytb had T as the terminating codon,COXIII’s termination codon was TA,and the remaining PCGs of that were TAA.All tRNA genes,except for the lacking DHU-arm of tRNASer(AGN),were predicted to form a typical cloverleaf secondary structure.In addition,sequence similarity analysis(99%identity)and phylogenetic analysis(100%bootstrap value)indicated that the mitochondrial genome was maternally inherited.This study provides mitogenome data for studying genetic,phylogenetic relationships and breeding of grouper.展开更多
Several reports have revealed the vital role that probiotics play in fish growth and health.However,few works are available for host gut-derived probiotics on the growth,immunity,and gut microbiota of fish,especially ...Several reports have revealed the vital role that probiotics play in fish growth and health.However,few works are available for host gut-derived probiotics on the growth,immunity,and gut microbiota of fish,especially in hybrid grouper (♀Epinephelus fuscoguttatus×♂Epinephelus lanceolatus) due to their isolation difficulty and functional verification.This study aimed at assessing 3 host gut-derived Bacillus species?effects on the growth,immune and antioxidant-biochemical responses,haematological parameters,intestinal morphology,immune-related gene expression,gut microbiota,and disease resistance against Vibrio harveyi in hybrid grouper.A total of 480 hybrid grouper (initial weight=9.03±0.02 g) were randomly allotted into 4 groups,namely,the group fed a basal diet without probiotic inclusion (control,B0),the group fed the basal diet with Bacillus velezensis GPSAK4 (BV),the group fed the basal diet with Bacillus subtilis GPSAK9 (BS),and the group fed the basal diet with Bacillus tequilensis GPSAK2 (BT) strains at 1.0×10^(9)CFU/g.After a 6-week feeding trial,the results revealed significant improvements (P<0.05) in the growth performance,whole fish-body proximate composition,blood haematological parameters,serum,liver,and intestinal biochemical indexes,intestinal morphology,and protection against V.harveyi pathogen in the probiotic-treated groups compared with the untreated.Additionally,the expressions of intestinal tight junction genes (occludin and ZO1),pro-and anti-inflammatory genes,including IL1β,IL6,IL8,TNFa,MyD88,IL10,and TGFβ,were upregulated (P<0.05) after Bacillus species administration.Host gut-derived Bacillus supplementation shaped the gut microbiota by significantly increasing (P<0.05) the relative abundance of Proteobacteria,Bacteroidetes,Actinobacteria (except the BS group),Acidobacteria(except the BT group),Cyanobacteria (except the BV and BT groups),and Verrucomicrobia phyla,as well as known beneficial genera (Romboutsia,Turicibacter,Epulopiscium,Clostridium_sensu_stricto 1 and 13,Lactobacillus,and Bacillus),but significantly decreased (P<0.05) the abundance of Firmicutes,Chloroflexi,and Fusobacteria phyla,and purported pathogenic genera (Staphylococcus and Photobacterium) compared with the control group.Collectively,the results suggest that B.velezensis GPSAK4,B.subtilis GPSAK9(especially this strain),B.tequilensis GPSAK2 dietary supplementation at 1.0×10^(9)CFU/g has positive effects on the intestinal health of hybrid grouper via microbial composition modulation,thus enhancing the assimilation and absorption of nutrients to boost fish growth,immunity,and disease resistance.展开更多
Due to diminishing fish meal(FM)supplies,superb protein(PRO)sources are needed for aquaculture,such as soy-based PRO.However,these can cause enteritis and even intestinal injury in fish when used at high proportions i...Due to diminishing fish meal(FM)supplies,superb protein(PRO)sources are needed for aquaculture,such as soy-based PRO.However,these can cause enteritis and even intestinal injury in fish when used at high proportions in feed.This research examines the effects of substituting soybean protein concentrate(SPC)for FM on the growth performance and intestinal balance of pearl gentian groupers and investigates the mechanism of SPC-induced enteritis.Experimental fish(n=720)were fed 1 of 3 following diets:(1)a 50%FM diet(control),(2)a diet with 20%of the FM substituted with SPC(group SPC20),and(3)a 40%SPC-substituted diet(SPC40).Fish were fed for 10 wk iso-nitrogenous(50%PRO)and iso-lipidic(10%lipid)diets.Groups SPC20 and SPC40 showed significantly lower developmental performance and intestinal structures than control.Group SPC40 had significantly higher expressions of pro-inflammatory-related genes,such as interleukin 1β(IL1β),IL12,IL17 and tumor necrosis factorαand significantly lower expressions of anti-inflammatory-related genes,such as IL5,IL10 and transforming growth factorβ1.Biochemical and 16S high-throughput sequencing showed that the abundance and functions of intestinal flora in group SPC40 were significantly affected(P<0.05),and there were significant correlations between operational taxonomic unit abundance variations and inflammatory gene expressions at genus level(P<0.05).The second-and third-generation full-length transcriptome sequence was used to analyze the mechanism of SPC-induced enteritis in pearl gentian groupers,which showed that enteritis induced by SPC may be caused by disturbances to intestinal immune function induced by an imbalance in intestinal nutrition and metabolism,such as the intestinal immunity network for IgA production pathway.However,it remains unclear as to which intestinal immune or nutritional imbalance is most important in enteritis development.This study provides a basis for further research into soy PRO-related enteritis in fish.展开更多
Groupers are dispersed worldwide in the tropical and subtropical waters.They are prized in the live reef fish trade,making them candidates with high market value and consumer demand.In the Asian-Pacific region,the bro...Groupers are dispersed worldwide in the tropical and subtropical waters.They are prized in the live reef fish trade,making them candidates with high market value and consumer demand.In the Asian-Pacific region,the brown-marbled grouper(Epinephelus fuscoguttatus)is widely adapted as an aquaculture species.However,health management remains a major concern in the stressful intensive culture process.The present review discusses techniques and current knowledge in the cultivation of E.fuscoguttatus towards healthy fish growth focusing on aspects of immunity,feed,and husbandry.Understanding how the fish immune system responds during infections provides insights into the intricate ways fish resist pathogens.This information is helpful when developing vaccination strategies or immunostimulant compounds to strengthen fish immunity.Feeds that are formulated according to the needs of the fish ensure optimal growth and using suitable alternative ingredients may lower production cost without compromising fish health.Good husbandry practices contribute to a favourable environment for the fish to grow,while interspecific hybridization may be a convenient approach to generate hardier species.Nevertheless,it has been noted that research in E.fuscoguttatus is relatively scarce in contrast to the closely-related orange-spotted grouper(E.coioides),which is used in the present article as a reference.Ultimately,the identified gaps in knowledge between the two species warrant species-specific research in E.fuscoguttatus to promote fish health and ensure continued success in aquaculture.展开更多
基金Supported by Special Project of Hainan Provincial Engineering Research Center(GCZX2013005)Technology Research and Development Project of Hainan Provincial Research Institutes(KYYS-2014-59,KYYS-2013-24,11-20410-0010)Applied Technology Research and Development and Demonstration Project of Hainan Province(ZDXM2015025)~~
文摘[目的]研究掌握褐点石斑鱼胚胎及仔稚幼鱼各期发育特征,以便高效的进行褐点石斑鱼的苗种培育。[方法]通过对海南养殖的褐点石斑鱼(Epinephelus fuscoguttatus)人工催产后自然产卵受精所得的受精卵的群体试验,研究了其胚胎及胚后发育各期的形态特征、发育时间以及神经系统、消化系统、循环系统的发生等。[结果]褐点石斑鱼受精卵圆球形,无色透明,单油球,卵径0.83~0.94 mm;依据发育进程其胚胎发育划分为受精卵阶段、卵裂阶段、囊胚阶段、原肠阶段、胚体形成阶段、孵化阶段共6个阶段;在水温28.4~31.9℃,盐度31~32‰,p H 8.4的海水中,褐点石斑鱼胚胎历时20 h47 min完成整个胚胎发育过程孵化出膜,孵化的生态学总积温为455.361℃·h;胚后发育依据卵黄囊、背鳍第二鳍棘、腹鳍棘及鳞片、体色的变化分为仔鱼期、稚鱼期及幼鱼期。仔鱼期根据卵黄囊的有无又分为前期仔鱼和后期仔鱼。褐点石斑鱼胚后发育过程中最显著的变化是第一腹鳍棘与第二背鳍棘以及鳍棘上小刺的长出与收回。[结论]该研究为褐点石斑鱼的大规模育苗生产提供基础参考资料。
基金supported by the project of National Science and Technology Supporting Plan (No. 2011BAD13B04)
文摘The impact of water temperature(24, 27, 30 and 33℃) and salinity(15, 20, 25, 30 and 33) on oxygen consumption(OCR) and ammonium excretion rate(AER) of ♀ Epinephelus fuscoguttatus ×♂ E. lanceolatus hybrid grouper juveniles(9.39 ± 0.07 g) were investigated under the fed and un-fed conditions. The results showed that the OCR and AER were significantly(P < 0.05) affected by temperature and salinity under both fed and un-fed conditions. When temperature was 24–33℃, the OCR and AER of fed hybrid grouper juveniles were 85.68%–129.52% and 125.78%–287.63%, respectively, higher than those of un-fed hybrid grouper juveniles. The O/N ratio, protein use(P_u), Q_(10)(respiration) and Q_(10)(excretion) of fed hybrid grouper juveniles were 14.43–24.01, 28.35% – 48.48%, 1.69 and 3.01, respectively. The O/N ratio, P_u, Q_(10)(respiration), Q_(10)(excretion) of un-fed hybrid grouper juveniles were 20.39 – 31.79, 22.16% – 34.34%, 1.23 and 1.17, respectively. When salinity was 15–33, the OCR and AER of fed hybrid grouper juveniles increased by 87.42% – 116.85% and 215.38% – 353.57%, respectively, over those of un-fed hybrid grouper juveniles. The O/N ratio and P_u of fed hybrid grouper juveniles were 14.48 – 17.78, 39.36% – 49.43%, respectively. The O/N ratio and Pu of un-fed hybrid grouper juveniles were 20.39 – 31.79 and 22.16% – 34.34%, respectively. The specific dynamic action(SDA) of hybrid grouper juveniles was mainly related to protein metabolism. The results had a guiding significance to the large-scale intensive aquaculture of hybrid grouper juveniles.
基金Supported by Special Fund for Construction of Hainan Key Laboratory and Engineering Technical Research Center(gczx2013005)Special Fund for Technology Development by Scientific Research Institutes of Hainan Province(KYYS-2014-59)+1 种基金Special Fund for Application Technology Development and Demonstration(ZDXM2015025)Hainan Provincial-level Department Budget Project
文摘The effects of temperature and pH on embryonic development and survival rate of newly hatched larvae of Epinephelus fuscoguttatus were discussed by single factor experiment method. Under a salinity of 31‰, fertilized eggs were incubated at different temperatures (17, 20, 23, 26, 29 (eontrol), 32, 35 ℃ ) and different pH values (5.5, 6.0, 6.5, 7.0, 7.5, 8.0, 8.4 (control), 8.5, 9.0, 9.5 and 10.0), the development rate of fertilized eggs, hatching rate, deformity rate, survival rate of newly hatched larvae, and optimum temperature and pH ranges for embryonic development were recorded and analyzed. The results showed that the incubation period y required by fertilized eggs was in remarkably negative correlation with temperature x, y =4 017. 3x-15277 , R2 =0. 971 3. At 29 ℃, the hatching rate was the highest, up to 92.00% ; this temperature was corresponding to the lowest deformity rate of newly hatched larvae ( 1.09% ) ; corresponding effective accumulative temperature was also the lowest (437. 410 ℃ . h), and significantly different from other experimental groups (P 〈 0.05 ) ; but on the contrary, corresponding survival rates at 24 and 48 h reached, respectively, 88.03% and 82. 97% which were significantly different from other experimental groups ( P 〈 0.05). At the pH of 8.4 in the CK group and the pH of 8.5 of one experimental group, the embryonic development rates were the highest; con-esponding hatching rates of fertilized eggs were the highest, respectively, of 88.33% and 83.33% which were significantly different from other groups (P 〈 0.05) ; and corresponding survival rates at 24 and 48 h were the highest, and reached 90.84% and 85.03%, respectively. In the pH range of 8.0 - 8.5, the deformity rate of newly hatched larvae was 0. It was indicating that for embryonic development of E. fuscoguttatus, the suitable water temperature value was in the range of 17 - 29 ℃, the optimum value was in the range of 23 -29℃; and the suitable pH value was in the range of 6.5 -9.5, and the optimum value was in the range of 8.0- 8.5.
文摘The present study was conducted as a continuation of our previous study on the effects of fish meal replacement with soy bean meal, SBM in the diets of tiger grouper, Epinephelus fuscoguttatus which revealed the possible level of fish meal protein replacement of 30% with positive effect of phytase supplementation in one of the test diet. In the present study, all experimental diets with SBM inclusion (10%, 20%, 30%, 40% replacement levels) were supplemented with phytase and fed to juvenile tiger grouper with initial body weight of 44.57 ± 0.28 g for eight weeks. Apart from the effects on growth performance, diet utilization and fish whole-body composition, apparent digestibility coefficient of diets was also measured. Similar findings to our previous experiment were observed in the present study. Diet SM40P (40% replacement level) had produced the poorest growth performance and feed conversion ratio (FCR). However, it was observed that FCR of SM40P was improved when compared to SM40 (without phytase) in our previous experiment. Other than that, SBM-based diets were performed as good as the control diet in terms of growth, feed utilization and survival rate. Replacement of fish meal did not significantly influence body composition, except for whole body lipid content in SM40P. In general, dry matter and protein apparent digestibility coefficients (ADC) of the test diets were influenced by SBM inclusion in the diets. However, crude lipid ADC was very high in all dietary treatments indicating efficient utilization of dietary lipid by juvenile tiger grouper. The findings of the present study confirmed that SBM can be used to replace FM at a level of up to 30% and supplementation of phytase in SBM-based diets is recommended to improve the diet performance.
文摘The effects of fish meal (FM) replacement with graded level of soybean meal (SBM) on growth performance, feed utilization, survival rate and body composition were investigated in juvenile tiger grouper, Epinephelus fuscoguttatus (initial body weight 13.9 ±0.65 g). Six experimental diets were formulated to contain 50% crude protein, 16% crude lipid and 365.8 kcal/100g feed with SBM replacing FM protein at 0% (SM 0), 10% (SM 0), 20% (SM 20), 30% (SM 30), 40% (SM 40) and 20% with phytase (SM 20P) replacement levels. At the end of the ten-week feeding trial, there were no significant differences detected in terms of growth performances (weight gain and specific growth rate), feed conversion ratio (FCR) and survival rates of fish fed with the control diet (SM 0), SM 20, SM 30 and SM 20P. Net protein utilization of fish fed SM 20P was higher than those fed with other diets suggesting an improved utilization of nutrients with phytase addition in the diet. Replacements of FM protein with SBM at 10% and 40% have resulted in significantly lower growth and poorer FCR than other replacement levels. Survival rates remain high (≥90%) throughout the trial. Whole-body proximate composition of the fish was significantly affected by the inclusion of SBM in the diets. It can be concluded that 20%-30% of FM protein replacement with SBM is recommended and addition of phytase in the SBM-based diet should be considered to improve nutrient utilization of tiger grouper juvenile.
基金The Key Research and Development Program of Shandong Province under contact No.2019GHY112063the Breeding Project of Shandong Province under contract No.2019LZGC020+1 种基金the Central Public-interest Scientific Institution Basal Research Fund Chinese Academy of Fishery Sciences under contract Nos 2020XT0601,2020TD19 and 2020TD25the Yellow Sea Fisheries Research Institute Research Fees under contract Nos 20603022019002 and 20603022020015
文摘The mitochondrial genome(mitogenome)of hybrid grouper Epinephelus moara(♀)×Epinephelus tukula(♂),a new hybrid progeny,can provide valuable information for analyzing phylogeny and molecular evolution.In this study,the mitogenome was analyzed using PCR amplification and sequenced,then the phylogenetic relationship of E.moara(♀)×E.tukula(♂)and 35 other species were constructed using Maximum Likelihood and NeighborJoining methods with the nucleotide sequences of 13 conserved protein-coding genes(PCGs).The complete mitogenome of E.moara(♀)×E.tukula(♂)was 16695 bp in length,which contained 13 PCGs,2 rRNA genes,22 tRNA genes,a replication origin and a control region.The composition and order of these genes were consistent with most other vertebrates.Of the 13 PCGs,12 PCGs were encoded on the heavy strand,and ND6 was encoded on the light strand.The mitogenome of the E.moara(♀)×E.tukula(♂)had a higher AT nucleotide content,a positive AT-skew and a negative GC-skew.All protein initiation codons were ATG,except for COX and ND4(GTG),ATP6(CTG),and ND3(ATA).ND2,COXII,ND3,ND4 and Cytb had T as the terminating codon,COXIII’s termination codon was TA,and the remaining PCGs of that were TAA.All tRNA genes,except for the lacking DHU-arm of tRNASer(AGN),were predicted to form a typical cloverleaf secondary structure.In addition,sequence similarity analysis(99%identity)and phylogenetic analysis(100%bootstrap value)indicated that the mitochondrial genome was maternally inherited.This study provides mitogenome data for studying genetic,phylogenetic relationships and breeding of grouper.
基金supported financially by the General Program of Natural Science Foundation of Guangdong Province(2021A1515011165)the Department of Education of Guangdong Province (2021ZDZX4005)+2 种基金the National Natural Science Foundation of China (31972808)the Research and Demonstration of Precision Functional Compound Feed Technology of Major Cultured Fishes and Shrimps in South China (2021B0202050002)the China Agriculture Research System of MOF and MARA (CARS-47)。
文摘Several reports have revealed the vital role that probiotics play in fish growth and health.However,few works are available for host gut-derived probiotics on the growth,immunity,and gut microbiota of fish,especially in hybrid grouper (♀Epinephelus fuscoguttatus×♂Epinephelus lanceolatus) due to their isolation difficulty and functional verification.This study aimed at assessing 3 host gut-derived Bacillus species?effects on the growth,immune and antioxidant-biochemical responses,haematological parameters,intestinal morphology,immune-related gene expression,gut microbiota,and disease resistance against Vibrio harveyi in hybrid grouper.A total of 480 hybrid grouper (initial weight=9.03±0.02 g) were randomly allotted into 4 groups,namely,the group fed a basal diet without probiotic inclusion (control,B0),the group fed the basal diet with Bacillus velezensis GPSAK4 (BV),the group fed the basal diet with Bacillus subtilis GPSAK9 (BS),and the group fed the basal diet with Bacillus tequilensis GPSAK2 (BT) strains at 1.0×10^(9)CFU/g.After a 6-week feeding trial,the results revealed significant improvements (P<0.05) in the growth performance,whole fish-body proximate composition,blood haematological parameters,serum,liver,and intestinal biochemical indexes,intestinal morphology,and protection against V.harveyi pathogen in the probiotic-treated groups compared with the untreated.Additionally,the expressions of intestinal tight junction genes (occludin and ZO1),pro-and anti-inflammatory genes,including IL1β,IL6,IL8,TNFa,MyD88,IL10,and TGFβ,were upregulated (P<0.05) after Bacillus species administration.Host gut-derived Bacillus supplementation shaped the gut microbiota by significantly increasing (P<0.05) the relative abundance of Proteobacteria,Bacteroidetes,Actinobacteria (except the BS group),Acidobacteria(except the BT group),Cyanobacteria (except the BV and BT groups),and Verrucomicrobia phyla,as well as known beneficial genera (Romboutsia,Turicibacter,Epulopiscium,Clostridium_sensu_stricto 1 and 13,Lactobacillus,and Bacillus),but significantly decreased (P<0.05) the abundance of Firmicutes,Chloroflexi,and Fusobacteria phyla,and purported pathogenic genera (Staphylococcus and Photobacterium) compared with the control group.Collectively,the results suggest that B.velezensis GPSAK4,B.subtilis GPSAK9(especially this strain),B.tequilensis GPSAK2 dietary supplementation at 1.0×10^(9)CFU/g has positive effects on the intestinal health of hybrid grouper via microbial composition modulation,thus enhancing the assimilation and absorption of nutrients to boost fish growth,immunity,and disease resistance.
基金This study received assistance from the National Key R&D Program of China(2019YFD0900200).
文摘Due to diminishing fish meal(FM)supplies,superb protein(PRO)sources are needed for aquaculture,such as soy-based PRO.However,these can cause enteritis and even intestinal injury in fish when used at high proportions in feed.This research examines the effects of substituting soybean protein concentrate(SPC)for FM on the growth performance and intestinal balance of pearl gentian groupers and investigates the mechanism of SPC-induced enteritis.Experimental fish(n=720)were fed 1 of 3 following diets:(1)a 50%FM diet(control),(2)a diet with 20%of the FM substituted with SPC(group SPC20),and(3)a 40%SPC-substituted diet(SPC40).Fish were fed for 10 wk iso-nitrogenous(50%PRO)and iso-lipidic(10%lipid)diets.Groups SPC20 and SPC40 showed significantly lower developmental performance and intestinal structures than control.Group SPC40 had significantly higher expressions of pro-inflammatory-related genes,such as interleukin 1β(IL1β),IL12,IL17 and tumor necrosis factorαand significantly lower expressions of anti-inflammatory-related genes,such as IL5,IL10 and transforming growth factorβ1.Biochemical and 16S high-throughput sequencing showed that the abundance and functions of intestinal flora in group SPC40 were significantly affected(P<0.05),and there were significant correlations between operational taxonomic unit abundance variations and inflammatory gene expressions at genus level(P<0.05).The second-and third-generation full-length transcriptome sequence was used to analyze the mechanism of SPC-induced enteritis in pearl gentian groupers,which showed that enteritis induced by SPC may be caused by disturbances to intestinal immune function induced by an imbalance in intestinal nutrition and metabolism,such as the intestinal immunity network for IgA production pathway.However,it remains unclear as to which intestinal immune or nutritional imbalance is most important in enteritis development.This study provides a basis for further research into soy PRO-related enteritis in fish.
基金Our research was supported by Malaysian Ministry of Education(MOE)Higher Institution Centre of Excellence(HICoE)Grant No.6369100Malaysian Ministry of Science,Technology and Innovation(MOSTI)EScience Fund No.5450576.
文摘Groupers are dispersed worldwide in the tropical and subtropical waters.They are prized in the live reef fish trade,making them candidates with high market value and consumer demand.In the Asian-Pacific region,the brown-marbled grouper(Epinephelus fuscoguttatus)is widely adapted as an aquaculture species.However,health management remains a major concern in the stressful intensive culture process.The present review discusses techniques and current knowledge in the cultivation of E.fuscoguttatus towards healthy fish growth focusing on aspects of immunity,feed,and husbandry.Understanding how the fish immune system responds during infections provides insights into the intricate ways fish resist pathogens.This information is helpful when developing vaccination strategies or immunostimulant compounds to strengthen fish immunity.Feeds that are formulated according to the needs of the fish ensure optimal growth and using suitable alternative ingredients may lower production cost without compromising fish health.Good husbandry practices contribute to a favourable environment for the fish to grow,while interspecific hybridization may be a convenient approach to generate hardier species.Nevertheless,it has been noted that research in E.fuscoguttatus is relatively scarce in contrast to the closely-related orange-spotted grouper(E.coioides),which is used in the present article as a reference.Ultimately,the identified gaps in knowledge between the two species warrant species-specific research in E.fuscoguttatus to promote fish health and ensure continued success in aquaculture.
文摘本试验旨在研究投喂频率对珍珠龙胆石斑鱼(Epinephelus fuscoguttatus♀×E.lanceolatu)生长性能、免疫、血清及肝脏生化指标的影响。在摄食高脂饲料的条件下,采用4种投喂频率(1、2、3、4次/d)投喂初始质量为(11.51±0.02)g的石斑鱼56 d,共360尾,每种投喂频率设3个重复,每个重复1个0.3 m 3玻璃钢桶,每桶30尾鱼。结果表明:1)1次/d组石斑鱼终末体质量(FBM)、增重率(WGR)及特定生长率(SGR)显著低于其他各组(P<0.05),其他各组间无显著差异(P>0.05)。2次/d组饲料系数(FCR)最低,显著低于1次/d组(P<0.05)。投喂频率对石斑鱼脏体比(VSI)、肝体比(HSI)与肥满度(CF)无显著影响(P>0.05)。2)1次/d组血清甘油三酯(TG)含量显著低于其他各组(P<0.05)。各组间血清总胆固醇(TC)含量无显著差异(P>0.05)。随着投喂频率的升高,血清低密度脂蛋白(LDL)含量呈逐渐降低趋势,在1次/d组有最大值,显著高于其他各组(P<0.05),血清高密度脂蛋白(HDL)含量则呈相反趋势,在1次/d组有最小值,显著低于其他各组(P<0.05),血清过氧化氢酶(CAT)与超氧化物歧化酶(SOD)活性呈上升的趋势,在4次/d组有最大值,显著高于其他各组(P<0.05)。血清总抗氧化能力(T-AOC)呈先上升后稳定的趋势,3、4次/d组显著高于1、2次/d组(P<0.05)。3)1次/d组肝脏T-AOC,CAT、SOD、溶菌酶(LYS)活性及免疫球蛋白(IgM)含量显著低于其他各组(P<0.05)。4)4次/d组肝脏TG含量显著高于其他各组(P<0.05)。1次/d组肝脏TC含量显著高于其他各组(P<0.05)。4次/d组肝脏极低密度脂蛋白(VLDL)含量显著低于其他各组(P<0.05)。4次/d组肝脏脂蛋白脂酶(LPL)活性显著高于其他各组(P<0.05),肝脏肝脂酶(HL)活性呈现上升趋势,3、4次/d组显著高于1、2次/d组(P<0.05)。3次/d组肝脏甘油三脂酶(ATGL)活性显著高于其他各组(P<0.05)。综上所述,适宜的投喂频率能提高石斑鱼的生长性能、抗氧化能力和脂代谢能力。本试验条件下,摄食高脂饲料石斑鱼的最佳投喂频率为2次/d。