Taking grass carps with the initial weight of about 20g as the research object,the basic feeds of grass carps were added with0.0%,0.1%,0.3%,0.6%,0.8%,and 1% of nano-sustained release sodium butyrate to prepare 6 types...Taking grass carps with the initial weight of about 20g as the research object,the basic feeds of grass carps were added with0.0%,0.1%,0.3%,0.6%,0.8%,and 1% of nano-sustained release sodium butyrate to prepare 6 types of experimental feeds with equal nitrogen and energy.The effects of different concentrations of nano-sustained release sodium butyrate were surveyed on growth and intestinal cell proliferation of grass carps.The experiment was carried out in cages with 50 carps per cage,and each treatment was repeated 3 times for60 days.Experimental results indicated that the addition of nano-sustained release sodium butyrate significantly promoted the growth of grass carps and significantly increased the ratio of intestinal villus to crypt depth.When the addition of nano-sustained release sodium butyrate was0.6%,the weight increase rate,specific growth rate,fullness and intestinal villus height of grass carps were the highest,which was significantly higher than that of the control group(P < 0.05).The study results indicated that addition of appropriate amount of nano-sustained release sodium butyrate can promote the growth of grass carps through increasing the intestinal villus height,and the suitable addition dosage was0.6%.展开更多
The study was carried out to find the prevalence of ectoparasites in carp species specifically Indian Major Carps(IMC)during the post monsoon season(November’16 to March’17).Four groups of ectoparasites viz.myxozoan...The study was carried out to find the prevalence of ectoparasites in carp species specifically Indian Major Carps(IMC)during the post monsoon season(November’16 to March’17).Four groups of ectoparasites viz.myxozoan,ciliophoran,monogenean and crustacean were recorded from a total 500 number of carp species like,Labeo rohita,Catla catla,Cirrhinus mrigala and Labeo calbasu collected from different ponds of selected blocks of South 24-Parganas district of West Bengal.The highest prevalence(64.8%)of infestation had been recorded by Myxozoans and the lowest was by Monogeneans(4.8%).The highest and lowest ectoparasitic prevalence in carp was observed in L.rohita(32.9%)and C.catla(27.3%).Beside these,lower temperature(Average 19.3℃),low pH(Average 6.9)and marginal level of dissolved oxygen(Average 6.0ppm)were also created an unfavorable condition for parasitic infestation during this season.At the end of this experiment it was concluded that disease occurrences due to ectoparasites was high in winter with some key factors like temperature,pH and dissolved oxygen(DO).展开更多
A fishers’women-led Participatory Action Research(PAR)was conducted in 30 homestead ponds to assess the potential for polyculture of Tilapia(Oreochromis niloticus)and major carps Rohu(Labeo rohita)and Catla(Catla cat...A fishers’women-led Participatory Action Research(PAR)was conducted in 30 homestead ponds to assess the potential for polyculture of Tilapia(Oreochromis niloticus)and major carps Rohu(Labeo rohita)and Catla(Catla catla)in two coastal fishing villages of Bangladesh.Three treatments,namely T1(Tilapia 200 fish per decimal;1 decimal=40 m^2),T2(Tilapia 200+Rohu 32+Catla 8 fish per decimal)and T3(Tilapia 200+Rohu 8+Catla 32 fish per decimal),each with 5 replicates,were tried in Hossainpur and Anipara villages.Formulated commercial Mega-feed was applied to the ponds twice daily at an initial rate of 10%body weight(bw)/day of Tilapia down to 4%bw/day throughout the culture period.The water quality parameters of ponds including transparency,salinity and dissolved oxygen significantly varied among treatments except temperature and pH and remained within optimum range for carp polyculture except salinity.The survival rate,harvesting weight and yield of Tilapia were significantly highest in T1(85.63±05%,258.59±18.76 g&11073±805 kg/ha,respectively)in Anipara and lowest in T3(75.63±0.37%,136.97±10.63 g&5180±406 kg/ha,respectively)in Hossainpur.The gross fish production was the significantly highest in T1(11354±806 kg/ha)of Anipara and lowest in T1(6325±227 kg/ha)of Hossainpur.Statistically,the highest net return(866,627±84874 BDT/ha)was found in T1 of Anipara and lowest in T3(279,389±46104 BDT/ha)of Hossainpur with a significantly higher benefit-cost ratio(BCR)obtained in T1(3.26±0.20)for Tilapia and lower in T3(1.58±0.10)for polyculture Tilapia and carp of Hossainpur.Therefore,it may be concluded that Tilapia production in small homestead coastal ponds has a higher potential than its mix with carps in polyculture for generating food and supplemental income opportunity for coastal fishers’women in Bangladesh.展开更多
The study was carried out to find the prevalence and severity of Argulus sp.in Indian Major Carps(IMCs)collected from Bhangore block of South 24 Parganas district of West Bengal during November 2018 to August 2019.Jan...The study was carried out to find the prevalence and severity of Argulus sp.in Indian Major Carps(IMCs)collected from Bhangore block of South 24 Parganas district of West Bengal during November 2018 to August 2019.January(2019)recorded the highest parasitic prevalence(PFI,83.33%)and the month of August(2019)recorded the lowest parasitic prevalence(PFI,9%).The identities of selected parasites were further confirmed by molecular identification through 18S rDNA analysis.The study revealed that Argulus sp.infestations had great economic implications especially in the winter months and is one of the most prevalent problems in fresh water aquaculture systems.展开更多
Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aq...Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aquaculture species in China.Reproduction of these carp has declined since the construction of the Three Gorges Dam(TGD) due to an altered water flow and thermal regime in the Changjiang(Yangtze) River.However,details of the changes in reproduction of the four species are not well understood.To assess the impact of the TGD on reproduction of the four carp,we investigated their eggs and larvae at Yidu City,which is 80 km below the TGD,during 2005-2012.We examined differences in larval abundance of the four species in the Jianli section(350 km downstream of the TGD) before(1997-2002)and after(2003-2012) construction of the TGD.Based on these observations,the first spawning date of the four species was delayed a mean of about 25 days after the dam was constructed.Mean egg abundance in the Yidu section of the river was 249 million and mean larval abundance was 464 million,which were significant decreases since the 1980 s.Moreover,larval abundance in the Jianli section after the dam was constructed was significantly lower than that before construction(ANCOVA,P<0.05).The observed larval abundance accounted for only 24.66%of the predicted value in 2003 when the dam was first inundated.The present spawning grounds between the TGD and Yidu section of the river are very similar to those described in the 1980 s,and some spawning grounds exist upstream of the TGD.Large free-flowing stretches upstream of the TGD and the creation of artificially flooded downstream reaches are needed to stimulate spawning and effectively conserve these four major Chinese carps species.展开更多
With carps as the object of study, the effects of benzo[a]pyrene concentration on SOD and CAT in carp kidneys were studied. There were three treatment groups and one control group. The exposure method was the static m...With carps as the object of study, the effects of benzo[a]pyrene concentration on SOD and CAT in carp kidneys were studied. There were three treatment groups and one control group. The exposure method was the static method. The superoxide dismutase (SOD) and catalase (CAT) activity was determined 30 d later. The results showed that after exposing to different concentrations of benzo[a]pyrene (0, 0.1, 0.5 and 1.0 μg /L) for 30 d, the SOD activity was higher in the low concentration group (0.1 μg/L) than in the control group; the 0.5 μg/L benzo[a]pyrene group had no significant difference from the control group; and under the concentration of 1.0 μg/L, the SOD activity decreased remarkably. The CAT activity was higher in the 0.1 μg/L group than in the control group, and decreased significantly in the 1.0 μg/L benzo[a]pyrene group compared with the control group. The results showed that benzo[a]pyrene had certain effects on the antioxidant enzymes in carp kidneys. This study provides a theoretical basis for water environmental pollution.展开更多
Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA a...Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear.This study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.Methods A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the control group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur group.Each treatment consisted of 3 replicates(180 fish)for 60 d.Results Firstly,we cultured,purified,and identified myoblasts using the tissue block culture method.Through preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect.Secondly,Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass carp.Then,Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling pathway.Finally,Cur could downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling pathway.Conclusions In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro.This study confirms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.展开更多
Carp is a temperate freshwater fish native to Asia,distributed in all regions of the world except Australia and South America.With the improvement of comprehensive and healthy breeding technology of carp,the unit yiel...Carp is a temperate freshwater fish native to Asia,distributed in all regions of the world except Australia and South America.With the improvement of comprehensive and healthy breeding technology of carp,the unit yield has been greatly increased mainly due to the exten-sive use of compound feed.In this study,the nutritional requirements of carp were summarized from the aspects of protein,amino acids,fat,carbohydrate,calcium and phosphorus,vitamins and taurine.This study provides a certain theoretical reference for scientific formula of carp feed.展开更多
During the present investigation,studies were carried out to investigate the outbreak of Redmouth disease in culture ponds situated at Krishna,West Godavari and East Godavari districts of Andhra Pradesh.Enteric Red Mo...During the present investigation,studies were carried out to investigate the outbreak of Redmouth disease in culture ponds situated at Krishna,West Godavari and East Godavari districts of Andhra Pradesh.Enteric Red Mouth disease or Yersiniosis is a serious infectious bacterial disease,sometimes responsible for causing severe economic loss to fish farming industry.The disease is clinically characterized by symptoms like bleeding at the base of fins,inside and around mouth,bilateral exophthalmia with or without haemorrhage,and per-ocular and peri-oral haemorrhages.In the present study,live or moribund fish showing lesions similar to enteric redmouth disease were collected and the causative agent was isolated by culture techniques.Bacterial identification was carried out by conventional biochemical methods and molecular polymerase chain reaction.DNA extracted from isolated pathogen was subjected to PCR amplification with a pair of Y.ruckeri specific primers.The PCR product was run on 1.5%agarose gel electrophoresis and positive bands with a molecular size of approximately 500bp were detected.It is similar to that given for PCR products with primers specific for Y.ruckeri.展开更多
The gastrointestinal(GI)microbiome in fish plays significant roles in health and disease resistance.This investigation was accomplished to enumerate,characterize and identify the potential probiotic bacteria from thre...The gastrointestinal(GI)microbiome in fish plays significant roles in health and disease resistance.This investigation was accomplished to enumerate,characterize and identify the potential probiotic bacteria from three Indian Major Carps(IMCs),viz.,rohu(Labeo rohita),catla(Catla catla)and mrigal(Cirrhinus mrigala)using culture dependent methods.Altogether,105 pathogen-inhibitory bacteria(out of 1216 isolates)were detected from three IMCs by double layer assay.16S rRNA partial gene sequence analyses and BLAST search in the NCBI GenBank unveiled that 94.29%of the pathogen inhibitory bacteria were bacilli(99 strains)and Bacillus licheniformis by far the most common(28%).The primarily selected 27 pathogen-inhibitory strains(cumulative inhibition score≥13)produced extracellular enzymes,while 15 of them produced all the six exo-enzymes studied(amylase,protease,lipase,cellulase,phytase and xylanase).Gut stability of the strains became apparent by their ability to grow in fish mucus and tolerance to diluted bile-juice.Finally,14 strains were noticed asγ-hemolytic and susceptible to the commonly used antibiotics.Further,intra-peritoneal injection withγ-hemolytic strains did not induce any pathological signs or mortalities in fish,and thus were considered as safe.These 14γ-hemolytic isolates were represented by the genus Bacillus(13)and Stenotrophomonas(1),which might form probiotic consortia for prospective use in carp culture.展开更多
The aim of the present study was to purify the common native carp growth hormone (ncGH), produce monoclonal antibodies (mAbs) to common native carp growth hormone (ncGH), and further enhance the sensitivity of enzyme-...The aim of the present study was to purify the common native carp growth hormone (ncGH), produce monoclonal antibodies (mAbs) to common native carp growth hormone (ncGH), and further enhance the sensitivity of enzyme-linked immunosorbent assays (ELISA) for ncGH. Additionally, we investigated changes in serum ncGH levels in carps raised in different environmental conditions. The recombinant grass carp (Ctenopharyngodon idella) growth hormone was purified and used as antigen to immunize the rabbit. The natural ncGH was isolated from the pituitaries of common carp. SDS-PAGE and Western blot utilizing the polyclonal anti-rgcGH antibody confirmed the purification of ncGH from pituitaries. Purified ncGH was then used as an immunogen in the B lymphocyte hybridoma technique. A total of 14 hybridoma cell lines (FMU-cGH 1-14) were established that were able to stably secrete mAbs against ncGH. Among them, eight clones (FMU-cGH1-6, 12 and 13) were successfully used for Western blot while nine clones (FMU-cGH 1-7, 9 and 10) were used in fluorescent staining and immunohistochemistry. Epitope mapping by competitive ELISA demonstrated that these mAbs recognized five different epitopes. A sensitive sandwich ELISA for detection of ncGH was developed using FMU-cGH12 as the coating mAb and FMU-cGH6 as the enzyme labeled mAb. This detection system was found to be highly stable and sensitive, with detection levels of 70 pg/mL. Additionally, we found that serum ncGH levels in restricted food group and in the net cage group increased 6.9-and 5.8-fold, respectively, when compared to controls, demonstrating differences in the GH stress response in common carp under different living conditions.展开更多
Background:Nutrient regulation has been proven to be an effective way to improve the flesh quality in fish.As a necessary nutrient for fish growth,protein accounts for the highest proportion in the fish diet and is ex...Background:Nutrient regulation has been proven to be an effective way to improve the flesh quality in fish.As a necessary nutrient for fish growth,protein accounts for the highest proportion in the fish diet and is expensive.Although our team found that the effect of protein on the muscle hardness of grass carp was probably related to an increased collagen content,the mechanism for this effect has not been deeply explored.Moreover,few studies have explored the protein requirements of sub-adult grass crap(Ctenopharyngodon idella).Therefore,the effects of different dietary protein levels on the growth performance,nutritional value,muscle hardness,muscle fiber growth,collagen metabolism and related molecule expression in grass carp were investigated.Methods:A total of 450 healthy grass carp(721.16±1.98 g)were selected and assigned randomly to six experimen-tal groups with three replicates each(n=25/replicate),and were fed six diets with 15.91%,19.39%,22.10%,25.59%,28.53%and 31.42%protein for 60 d.Results:Appropriate levels of dietary protein increased the feed intake,percentage weight gain,specific growth rate,body composition,unsaturated fatty acid content in muscle,partial free amino acid content in muscle,and muscle hardness of grass carp.These protein levels also increased the muscle fiber density,the frequency of new muscle fibers,the contents of collagen and IGF-1,and the enzyme activities of prolyl 4-hydroxylases and lysyloxidase,and decreased the activity of matrix metalloproteinase-2.At the molecular level,the optimal dietary protein increased col-lagen type Iα1(Colα1),Colα2,PI3K,Akt,S6K1,La ribonucleoprotein domain family member 6a(LARP6a),TGF-β1,Smad2,Smad4,Smad3,tissue inhibitor of metalloproteinase-2,MyoD,Myf5,MyoG and MyHC relative mRNA levels.The levels of the myostatin-1 and myostatin-2 genes were downregulated,and the protein expression levels of p-Smad2,Smad2,Smad4,p-Akt,Akt,LARP6 and Smad3 were increased.Conclusions:The appropriate levels of dietary protein promoted the growth of sub-adult grass carp and improved muscle hardness by promoting the growth of muscle fibers,improving collagen synthesis and depressing collagen degradation.In addition,the dietary protein requirements of sub-adult grass carp were 26.21%and 24.85%according to the quadratic regression analysis of growth performance(SGR)and the muscle hardness(collagen content),respectively.展开更多
Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen...Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.展开更多
Background Muscle represents a unique and complex system with many components and comprises the major edible part of animals.Vitamin D is a critical nutrient for animals and is known to enhance calcium absorption and ...Background Muscle represents a unique and complex system with many components and comprises the major edible part of animals.Vitamin D is a critical nutrient for animals and is known to enhance calcium absorption and immune response.In recent years,dietary vitamin D supplementation in livestock has received increased attention due to biological responses including improving shear force in mammalian meat.However,the vitamin D acquisition and myofiber development processes in fish differ from those in mammals,and the effect of vitamin D on fish flesh quality is poorly understood.Here,the influence of dietary vitamin D on fillet quality,antioxidant ability,and myofiber development was examined in grass carp(Ctenopharyngodon idella).Methods A total of 540 healthy grass carp,with an initial average body weight of 257.24±0.63 g,were allotted in 6 experimental groups with 3 replicates each,and respectively fed corresponding diets with 15.2,364.3,782.5,1,167.9,1,573.8,and 1,980.1 IU/kg vitamin D for 70 d.Results Supplementation with 1,167.9 IU/kg vitamin D significantly improved nutritional value and sensory quality of fillets,enhancing crude protein,free amino acid,lipid,and collagen contents;maintaining an ideal pH;and reduc-ing lactate content,shear force,and cooking loss relative to respective values in the control(15.2 IU/kg)group.Average myofiber diameter and the frequency of myofibers>50μm in diameter increased under supplementation with 782.5–1,167.9 IU/kg vitamin D.Levels of oxidative damage biomarkers decreased,and the expression of antioxi-dant enzymes and nuclear factor erythroid 2-related factor 2 signaling molecules was upregulated in the 1,167.9 IU/kg vitamin D treatment compared to respective values in the control group.Furthermore,vitamin D supplementation activated cell differentiation by enhancing the expression of myogenic regulatory factors and myocyte enhancer factors compared to that in the control group.In addition,supplementation with 1,167.9 IU/kg vitamin D improved protein deposition associated with protein synthesis molecule(target of rapamycin)signaling and vitamin D receptor paralogs,along with inhibition of protein degradation(forkhead box protein 1)signaling.Conclusions Overall,the results demonstrated that vitamin D strengthened antioxidant ability and myofiber devel-opment,thereby enhancing nutritional value and sensory quality of fish flesh.These findings suggest that dietary vitamin D supplementation is conducive to the production of nutrient-rich,high quality aquaculture products.展开更多
In this study, a gene encoding serine protease(PmSpr288)from cold-adapted bacterium, namely Planococcus maritimus XJ11, was cloned and overexpressed in Escherichia coli BL21(DE3). Bioinformatics analysis revealed that...In this study, a gene encoding serine protease(PmSpr288)from cold-adapted bacterium, namely Planococcus maritimus XJ11, was cloned and overexpressed in Escherichia coli BL21(DE3). Bioinformatics analysis revealed that PmSpr288 belongs to serine protease S8 superfamily with a classical catalytic triad comprised by the Asp49, His86 and Ser251. Moreover, PmSpr288 was found to be active over broad alkaline pH and low-moderate temperature, and exhibited wide range of protein substrate specificity. In addition, PmSpr288 was able to hydrolyze the meat proteins actin and myosin, and molecular docking results suggested that the crucial interaction between PmSpr288 and actin/myosin complexes was mainly occupied by hydrogen bonds. The muscle protein hydrolysates of silver carp prepared by PmSpr288 was shown to have antioxidant activity via DPPH radical scavenging assay, which presented an IC_(50) valve of 1.309 mg/mL. In conclusion, these characteristics imply that PmSpr288 has potential biotechnological application prospect for the production of bioactive peptides.展开更多
基金Supported by Science and Technology Planning Project of Changsha City(k1407023-31)
文摘Taking grass carps with the initial weight of about 20g as the research object,the basic feeds of grass carps were added with0.0%,0.1%,0.3%,0.6%,0.8%,and 1% of nano-sustained release sodium butyrate to prepare 6 types of experimental feeds with equal nitrogen and energy.The effects of different concentrations of nano-sustained release sodium butyrate were surveyed on growth and intestinal cell proliferation of grass carps.The experiment was carried out in cages with 50 carps per cage,and each treatment was repeated 3 times for60 days.Experimental results indicated that the addition of nano-sustained release sodium butyrate significantly promoted the growth of grass carps and significantly increased the ratio of intestinal villus to crypt depth.When the addition of nano-sustained release sodium butyrate was0.6%,the weight increase rate,specific growth rate,fullness and intestinal villus height of grass carps were the highest,which was significantly higher than that of the control group(P < 0.05).The study results indicated that addition of appropriate amount of nano-sustained release sodium butyrate can promote the growth of grass carps through increasing the intestinal villus height,and the suitable addition dosage was0.6%.
文摘The study was carried out to find the prevalence of ectoparasites in carp species specifically Indian Major Carps(IMC)during the post monsoon season(November’16 to March’17).Four groups of ectoparasites viz.myxozoan,ciliophoran,monogenean and crustacean were recorded from a total 500 number of carp species like,Labeo rohita,Catla catla,Cirrhinus mrigala and Labeo calbasu collected from different ponds of selected blocks of South 24-Parganas district of West Bengal.The highest prevalence(64.8%)of infestation had been recorded by Myxozoans and the lowest was by Monogeneans(4.8%).The highest and lowest ectoparasitic prevalence in carp was observed in L.rohita(32.9%)and C.catla(27.3%).Beside these,lower temperature(Average 19.3℃),low pH(Average 6.9)and marginal level of dissolved oxygen(Average 6.0ppm)were also created an unfavorable condition for parasitic infestation during this season.At the end of this experiment it was concluded that disease occurrences due to ectoparasites was high in winter with some key factors like temperature,pH and dissolved oxygen(DO).
文摘A fishers’women-led Participatory Action Research(PAR)was conducted in 30 homestead ponds to assess the potential for polyculture of Tilapia(Oreochromis niloticus)and major carps Rohu(Labeo rohita)and Catla(Catla catla)in two coastal fishing villages of Bangladesh.Three treatments,namely T1(Tilapia 200 fish per decimal;1 decimal=40 m^2),T2(Tilapia 200+Rohu 32+Catla 8 fish per decimal)and T3(Tilapia 200+Rohu 8+Catla 32 fish per decimal),each with 5 replicates,were tried in Hossainpur and Anipara villages.Formulated commercial Mega-feed was applied to the ponds twice daily at an initial rate of 10%body weight(bw)/day of Tilapia down to 4%bw/day throughout the culture period.The water quality parameters of ponds including transparency,salinity and dissolved oxygen significantly varied among treatments except temperature and pH and remained within optimum range for carp polyculture except salinity.The survival rate,harvesting weight and yield of Tilapia were significantly highest in T1(85.63±05%,258.59±18.76 g&11073±805 kg/ha,respectively)in Anipara and lowest in T3(75.63±0.37%,136.97±10.63 g&5180±406 kg/ha,respectively)in Hossainpur.The gross fish production was the significantly highest in T1(11354±806 kg/ha)of Anipara and lowest in T1(6325±227 kg/ha)of Hossainpur.Statistically,the highest net return(866,627±84874 BDT/ha)was found in T1 of Anipara and lowest in T3(279,389±46104 BDT/ha)of Hossainpur with a significantly higher benefit-cost ratio(BCR)obtained in T1(3.26±0.20)for Tilapia and lower in T3(1.58±0.10)for polyculture Tilapia and carp of Hossainpur.Therefore,it may be concluded that Tilapia production in small homestead coastal ponds has a higher potential than its mix with carps in polyculture for generating food and supplemental income opportunity for coastal fishers’women in Bangladesh.
文摘The study was carried out to find the prevalence and severity of Argulus sp.in Indian Major Carps(IMCs)collected from Bhangore block of South 24 Parganas district of West Bengal during November 2018 to August 2019.January(2019)recorded the highest parasitic prevalence(PFI,83.33%)and the month of August(2019)recorded the lowest parasitic prevalence(PFI,9%).The identities of selected parasites were further confirmed by molecular identification through 18S rDNA analysis.The study revealed that Argulus sp.infestations had great economic implications especially in the winter months and is one of the most prevalent problems in fresh water aquaculture systems.
基金Supported by the Three Gorges Project Eco-Environmental Monitoring System(No.JJ[2015]-010)the China Three Gorges Corporation(No.0704097,0799533)
文摘Silver carp(Hypophthalmichthys molitrix),bighead carp(Aristichthys nobilis),grass carp(Ctenopharyngodon idella),and black carp(Mylopharyngodon piceus) are the four major Chinese carps and are commercially important aquaculture species in China.Reproduction of these carp has declined since the construction of the Three Gorges Dam(TGD) due to an altered water flow and thermal regime in the Changjiang(Yangtze) River.However,details of the changes in reproduction of the four species are not well understood.To assess the impact of the TGD on reproduction of the four carp,we investigated their eggs and larvae at Yidu City,which is 80 km below the TGD,during 2005-2012.We examined differences in larval abundance of the four species in the Jianli section(350 km downstream of the TGD) before(1997-2002)and after(2003-2012) construction of the TGD.Based on these observations,the first spawning date of the four species was delayed a mean of about 25 days after the dam was constructed.Mean egg abundance in the Yidu section of the river was 249 million and mean larval abundance was 464 million,which were significant decreases since the 1980 s.Moreover,larval abundance in the Jianli section after the dam was constructed was significantly lower than that before construction(ANCOVA,P<0.05).The observed larval abundance accounted for only 24.66%of the predicted value in 2003 when the dam was first inundated.The present spawning grounds between the TGD and Yidu section of the river are very similar to those described in the 1980 s,and some spawning grounds exist upstream of the TGD.Large free-flowing stretches upstream of the TGD and the creation of artificially flooded downstream reaches are needed to stimulate spawning and effectively conserve these four major Chinese carps species.
基金Supported by Top-notch Academic Programs Project of Jiangsu Higher Education Institutions(PPZY2015C230)
文摘With carps as the object of study, the effects of benzo[a]pyrene concentration on SOD and CAT in carp kidneys were studied. There were three treatment groups and one control group. The exposure method was the static method. The superoxide dismutase (SOD) and catalase (CAT) activity was determined 30 d later. The results showed that after exposing to different concentrations of benzo[a]pyrene (0, 0.1, 0.5 and 1.0 μg /L) for 30 d, the SOD activity was higher in the low concentration group (0.1 μg/L) than in the control group; the 0.5 μg/L benzo[a]pyrene group had no significant difference from the control group; and under the concentration of 1.0 μg/L, the SOD activity decreased remarkably. The CAT activity was higher in the 0.1 μg/L group than in the control group, and decreased significantly in the 1.0 μg/L benzo[a]pyrene group compared with the control group. The results showed that benzo[a]pyrene had certain effects on the antioxidant enzymes in carp kidneys. This study provides a theoretical basis for water environmental pollution.
基金financially supported by the earmarked fund for CARS(CARS-45)National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)+1 种基金the Young Top-Notch Talent Support Programthe 111 project(D17015)。
文摘Background Ochratoxin A(OTA),a globally abundant and extremely hazardous pollutant,is a significant source of contamination in aquafeeds and is responsible for severe food pollution.The developmental toxicity of OTA and the potential relieving strategy of natural products remain unclear.This study screened the substance curcumin(Cur),which had the best effect in alleviating OTA inhibition of myoblast proliferation,from 96 natural products and investigated its effect and mechanism in reducing OTA myotoxicity in vivo and in vitro.Methods A total of 720 healthy juvenile grass carp,with an initial average body weight of 11.06±0.05 g,were randomly assigned into 4 groups:the control group(without OTA and Cur),1.2 mg/kg OTA group,400 mg/kg Cur group,and 1.2 mg/kg OTA+400 mg/kg Cur group.Each treatment consisted of 3 replicates(180 fish)for 60 d.Results Firstly,we cultured,purified,and identified myoblasts using the tissue block culture method.Through preliminary screening and re-screening of 96 substances,we examined cell proliferation-related indicators such as cell viability and ultimately found that Cur had the best effect.Secondly,Cur could alleviate OTA-inhibited myoblast differentiation and myofibrillar development-related proteins(Myo G and MYHC)in vivo and in vitro and improve the growth performance of grass carp.Then,Cur could also promote the expression of OTA-inhibited protein synthesis-related proteins(S6K1 and TOR),which was related to the activation of the AKT/TOR signaling pathway.Finally,Cur could downregulate the expression of OTA-enhanced protein degradation-related genes(murf1,foxo3a,and ub),which was related to the inhibition of the Fox O3a signaling pathway.Conclusions In summary,our data demonstrated the effectiveness of Cur in alleviating OTA myotoxicity in vivo and in vitro.This study confirms the rapidity,feasibility,and effectiveness of establishing a natural product screening method targeting myoblasts to alleviate fungal toxin toxicity.
文摘Carp is a temperate freshwater fish native to Asia,distributed in all regions of the world except Australia and South America.With the improvement of comprehensive and healthy breeding technology of carp,the unit yield has been greatly increased mainly due to the exten-sive use of compound feed.In this study,the nutritional requirements of carp were summarized from the aspects of protein,amino acids,fat,carbohydrate,calcium and phosphorus,vitamins and taurine.This study provides a certain theoretical reference for scientific formula of carp feed.
基金The financial support was provided by a fellowship Grant from“Maulana Azad National Fellowship Programme”New Delhi,India.
文摘During the present investigation,studies were carried out to investigate the outbreak of Redmouth disease in culture ponds situated at Krishna,West Godavari and East Godavari districts of Andhra Pradesh.Enteric Red Mouth disease or Yersiniosis is a serious infectious bacterial disease,sometimes responsible for causing severe economic loss to fish farming industry.The disease is clinically characterized by symptoms like bleeding at the base of fins,inside and around mouth,bilateral exophthalmia with or without haemorrhage,and per-ocular and peri-oral haemorrhages.In the present study,live or moribund fish showing lesions similar to enteric redmouth disease were collected and the causative agent was isolated by culture techniques.Bacterial identification was carried out by conventional biochemical methods and molecular polymerase chain reaction.DNA extracted from isolated pathogen was subjected to PCR amplification with a pair of Y.ruckeri specific primers.The PCR product was run on 1.5%agarose gel electrophoresis and positive bands with a molecular size of approximately 500bp were detected.It is similar to that given for PCR products with primers specific for Y.ruckeri.
基金University Grants Commission(UGC-SAP-DRS programme),New Delhi,IndiaDepartment of Science and Technology(FIST and PURSE programmes),New Delhi,India for research support.
文摘The gastrointestinal(GI)microbiome in fish plays significant roles in health and disease resistance.This investigation was accomplished to enumerate,characterize and identify the potential probiotic bacteria from three Indian Major Carps(IMCs),viz.,rohu(Labeo rohita),catla(Catla catla)and mrigal(Cirrhinus mrigala)using culture dependent methods.Altogether,105 pathogen-inhibitory bacteria(out of 1216 isolates)were detected from three IMCs by double layer assay.16S rRNA partial gene sequence analyses and BLAST search in the NCBI GenBank unveiled that 94.29%of the pathogen inhibitory bacteria were bacilli(99 strains)and Bacillus licheniformis by far the most common(28%).The primarily selected 27 pathogen-inhibitory strains(cumulative inhibition score≥13)produced extracellular enzymes,while 15 of them produced all the six exo-enzymes studied(amylase,protease,lipase,cellulase,phytase and xylanase).Gut stability of the strains became apparent by their ability to grow in fish mucus and tolerance to diluted bile-juice.Finally,14 strains were noticed asγ-hemolytic and susceptible to the commonly used antibiotics.Further,intra-peritoneal injection withγ-hemolytic strains did not induce any pathological signs or mortalities in fish,and thus were considered as safe.These 14γ-hemolytic isolates were represented by the genus Bacillus(13)and Stenotrophomonas(1),which might form probiotic consortia for prospective use in carp culture.
基金the Development Plan of the State Key Fundamental Research ofChina(Grant No.2007CB109206)Chinese National Programs for High Technology Research and Development(Grant No.2006AA10Z141)the National NaturalScience Foundation of China(Grant No.30130050)
文摘The aim of the present study was to purify the common native carp growth hormone (ncGH), produce monoclonal antibodies (mAbs) to common native carp growth hormone (ncGH), and further enhance the sensitivity of enzyme-linked immunosorbent assays (ELISA) for ncGH. Additionally, we investigated changes in serum ncGH levels in carps raised in different environmental conditions. The recombinant grass carp (Ctenopharyngodon idella) growth hormone was purified and used as antigen to immunize the rabbit. The natural ncGH was isolated from the pituitaries of common carp. SDS-PAGE and Western blot utilizing the polyclonal anti-rgcGH antibody confirmed the purification of ncGH from pituitaries. Purified ncGH was then used as an immunogen in the B lymphocyte hybridoma technique. A total of 14 hybridoma cell lines (FMU-cGH 1-14) were established that were able to stably secrete mAbs against ncGH. Among them, eight clones (FMU-cGH1-6, 12 and 13) were successfully used for Western blot while nine clones (FMU-cGH 1-7, 9 and 10) were used in fluorescent staining and immunohistochemistry. Epitope mapping by competitive ELISA demonstrated that these mAbs recognized five different epitopes. A sensitive sandwich ELISA for detection of ncGH was developed using FMU-cGH12 as the coating mAb and FMU-cGH6 as the enzyme labeled mAb. This detection system was found to be highly stable and sensitive, with detection levels of 70 pg/mL. Additionally, we found that serum ncGH levels in restricted food group and in the net cage group increased 6.9-and 5.8-fold, respectively, when compared to controls, demonstrating differences in the GH stress response in common carp under different living conditions.
基金supported by National Key R&D Program of China(2018YFD0900400,2019YFD0900200)National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)+3 种基金National Nature Science Foundation of China(32172988)the Young Top-Notch Talent Support Program of National Ten-Thousand Talents Program,the Earmarked Fund for China Agriculture Research System(CARS-45)Outstanding Talents and Innovative Team of Agricultural Scientific Research(Ministry of Agriculture)Supported by Sichuan Science and Technology Program(2019YFN0036).
文摘Background:Nutrient regulation has been proven to be an effective way to improve the flesh quality in fish.As a necessary nutrient for fish growth,protein accounts for the highest proportion in the fish diet and is expensive.Although our team found that the effect of protein on the muscle hardness of grass carp was probably related to an increased collagen content,the mechanism for this effect has not been deeply explored.Moreover,few studies have explored the protein requirements of sub-adult grass crap(Ctenopharyngodon idella).Therefore,the effects of different dietary protein levels on the growth performance,nutritional value,muscle hardness,muscle fiber growth,collagen metabolism and related molecule expression in grass carp were investigated.Methods:A total of 450 healthy grass carp(721.16±1.98 g)were selected and assigned randomly to six experimen-tal groups with three replicates each(n=25/replicate),and were fed six diets with 15.91%,19.39%,22.10%,25.59%,28.53%and 31.42%protein for 60 d.Results:Appropriate levels of dietary protein increased the feed intake,percentage weight gain,specific growth rate,body composition,unsaturated fatty acid content in muscle,partial free amino acid content in muscle,and muscle hardness of grass carp.These protein levels also increased the muscle fiber density,the frequency of new muscle fibers,the contents of collagen and IGF-1,and the enzyme activities of prolyl 4-hydroxylases and lysyloxidase,and decreased the activity of matrix metalloproteinase-2.At the molecular level,the optimal dietary protein increased col-lagen type Iα1(Colα1),Colα2,PI3K,Akt,S6K1,La ribonucleoprotein domain family member 6a(LARP6a),TGF-β1,Smad2,Smad4,Smad3,tissue inhibitor of metalloproteinase-2,MyoD,Myf5,MyoG and MyHC relative mRNA levels.The levels of the myostatin-1 and myostatin-2 genes were downregulated,and the protein expression levels of p-Smad2,Smad2,Smad4,p-Akt,Akt,LARP6 and Smad3 were increased.Conclusions:The appropriate levels of dietary protein promoted the growth of sub-adult grass carp and improved muscle hardness by promoting the growth of muscle fibers,improving collagen synthesis and depressing collagen degradation.In addition,the dietary protein requirements of sub-adult grass carp were 26.21%and 24.85%according to the quadratic regression analysis of growth performance(SGR)and the muscle hardness(collagen content),respectively.
基金financially supported by the National Key R&D Program of China(2019YFD0900200,2018YFD0900400)Supported by the earmarked fund for CARS(CARS-45)+2 种基金National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)the Young Top-Notch Talent Support ProgramSichuan Science and Technology Program(2019YFN0036)。
文摘Background Mannan oligosaccharides(MOS)are recommended as aquaculture additives owing to their excellent antioxidant properties.In the present study,we examined the effects of dietary MOS on the head kidney and spleen of grass carp(Ctenopharyngodon idella)with Aeromonas hydrophila infection.Methods A total of 540 grass carp were used for the study.They were administered six gradient dosages of the MOS diet(0,200,400,600,800,and 1,000 mg/kg)for 60 d.Subsequently,we performed a 14-day Aeromonas hydrophila challenge experiment.The antioxidant capacity of the head kidney and spleen were examined using spectrophotometry,DNA fragmentation,qRT-PCR,and Western blotting.Results After infection with Aeromonas hydrophila,400-600 mg/kg MOS supplementation decreased the levels of reactive oxygen species,protein carbonyl,and malonaldehyde and increased the levels of anti-superoxide anion,antihydroxyl radical,and glutathione in the head kidney and spleen of grass carp.The activities of copper-zinc superoxide dismutase,manganese superoxide dismutase,catalase,glutathione S-transferase,glutathione reductase,and glutathione peroxidase were also enhanced by supplementation with 400-600 mg/kg MOS.Furthermore,the expression of most antioxidant enzymes and their corresponding genes increased significantly with supplementation of 200-800 mg/kg MOS.mRNA and protein levels of nuclear factor erythroid 2-related factor 2 also increased following supplementation with 400-600 mg/kg MOS.In addition,supplementation with 400-600 mg/kg MOS reduced excessive apoptosis by inhibiting the death receptor pathway and mitochondrial pathway processes.Conclusions Based on the quadratic regression analysis of the above biomarkers(reactive oxygen species,malondialdehyde,and protein carbonyl)of oxidative damage in the head kidney and spleen of on-growing grass carp,the recommended MOS supplementation is 575.21,557.58,531.86,597.35,570.16,and 553.80 mg/kg,respectively.Collectively,MOS supplementation could alleviate oxidative injury in the head kidney and spleen of grass carp infected with Aeromonas hydrophila.
基金National Key R&D Program of China(2018YFD0900400 and 2019YFD0900200)National Natural Science Foundation of China for Outstanding Youth Science Foundation(31922086)+1 种基金the earmarked fund for CARS(CARS-45)Sichuan Science and Technology Program(2019YFN0036).
文摘Background Muscle represents a unique and complex system with many components and comprises the major edible part of animals.Vitamin D is a critical nutrient for animals and is known to enhance calcium absorption and immune response.In recent years,dietary vitamin D supplementation in livestock has received increased attention due to biological responses including improving shear force in mammalian meat.However,the vitamin D acquisition and myofiber development processes in fish differ from those in mammals,and the effect of vitamin D on fish flesh quality is poorly understood.Here,the influence of dietary vitamin D on fillet quality,antioxidant ability,and myofiber development was examined in grass carp(Ctenopharyngodon idella).Methods A total of 540 healthy grass carp,with an initial average body weight of 257.24±0.63 g,were allotted in 6 experimental groups with 3 replicates each,and respectively fed corresponding diets with 15.2,364.3,782.5,1,167.9,1,573.8,and 1,980.1 IU/kg vitamin D for 70 d.Results Supplementation with 1,167.9 IU/kg vitamin D significantly improved nutritional value and sensory quality of fillets,enhancing crude protein,free amino acid,lipid,and collagen contents;maintaining an ideal pH;and reduc-ing lactate content,shear force,and cooking loss relative to respective values in the control(15.2 IU/kg)group.Average myofiber diameter and the frequency of myofibers>50μm in diameter increased under supplementation with 782.5–1,167.9 IU/kg vitamin D.Levels of oxidative damage biomarkers decreased,and the expression of antioxi-dant enzymes and nuclear factor erythroid 2-related factor 2 signaling molecules was upregulated in the 1,167.9 IU/kg vitamin D treatment compared to respective values in the control group.Furthermore,vitamin D supplementation activated cell differentiation by enhancing the expression of myogenic regulatory factors and myocyte enhancer factors compared to that in the control group.In addition,supplementation with 1,167.9 IU/kg vitamin D improved protein deposition associated with protein synthesis molecule(target of rapamycin)signaling and vitamin D receptor paralogs,along with inhibition of protein degradation(forkhead box protein 1)signaling.Conclusions Overall,the results demonstrated that vitamin D strengthened antioxidant ability and myofiber devel-opment,thereby enhancing nutritional value and sensory quality of fish flesh.These findings suggest that dietary vitamin D supplementation is conducive to the production of nutrient-rich,high quality aquaculture products.
基金supported by China Agriculture Research System of MOF and MARA,CARS-46。
文摘In this study, a gene encoding serine protease(PmSpr288)from cold-adapted bacterium, namely Planococcus maritimus XJ11, was cloned and overexpressed in Escherichia coli BL21(DE3). Bioinformatics analysis revealed that PmSpr288 belongs to serine protease S8 superfamily with a classical catalytic triad comprised by the Asp49, His86 and Ser251. Moreover, PmSpr288 was found to be active over broad alkaline pH and low-moderate temperature, and exhibited wide range of protein substrate specificity. In addition, PmSpr288 was able to hydrolyze the meat proteins actin and myosin, and molecular docking results suggested that the crucial interaction between PmSpr288 and actin/myosin complexes was mainly occupied by hydrogen bonds. The muscle protein hydrolysates of silver carp prepared by PmSpr288 was shown to have antioxidant activity via DPPH radical scavenging assay, which presented an IC_(50) valve of 1.309 mg/mL. In conclusion, these characteristics imply that PmSpr288 has potential biotechnological application prospect for the production of bioactive peptides.