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1.
Gibel carp (Carassius auratus gibelio) of mean initial weight 3.1 g were fed one of seven casein‐dextrin‐based diets containing graded levels of magnesium (Mg) (39, 120, 220, 380, 700, 1600 and 2900 mg kg?1) for 3 months with the waterborne Mg concentration of 10.6–12.7 mg L?1. Magnesium sulphate was used as the supplementation Mg source in the diets. The experiment was carried out in a flow‐through system. Growth, survival rate, Na+/K+‐ATPase, Mg2+‐ATPase and tissue mineral contents were measured to investigate the effect of dietary magnesium in gibel carp. At the end of the experiment, the hepatopancreas of fish were collected for enzyme determination. The hepatopancreas, vertebrae and whole body were collected for tissue magnesium content analysis. After 3 months, dietary magnesium supplementation did not improve the growth performance, including feed intake, weight gain and feed conversion efficiency of juvenile gibel carp. On the contrary, negative impacts on survival, reduced growth performance and dramatically decreased Na+/K+‐ATPase, Mg2+‐ATPase and superoxide dismutase activities were observed in gibel carp fed a high Mg diet of 2900 mg kg?1. Although serum and hepatopancreas Mg and Ca contents were not affected by dietary Mg supplementation, vertebrae and whole‐body Mg contents increased significantly with the increasing dietary Mg concentrations. Based on the relationship between whole‐body Mg retention and dietary Mg concentration, a suitable dietary Mg level of 745 mg kg?1 could be estimated for gibel carp. It could be concluded that dietary Mg supplementation did not improve the growth performance, but could increase vertebrae Mg contents of gibel carp. Considering the adverse effects, a dietary Mg concentration of above 2900 mg kg?1 is not recommended and it should be careful to supplement magnesium in practical diets for gibel carp as most feed ingredients contain high magnesium concentrations.  相似文献   

2.
D. Xie  D. Han  X. Zhu  Y. Yang  J. Jin  H. Liu  S. Xie 《Aquaculture Nutrition》2017,23(5):1104-1112
A nine‐week feeding experiment was conducted in flow‐through system with gibel carp (43.8 ± 0.2 g) to study the effects of dietary available phosphorus (P) on growth, phosphorous digestibility and intestinal enzyme activities. Seven semipurified diets were formulated to contain 0.8 (the basal), 2.4, 3.6, 6.1, 7.4, 10.1 and 15.8 g available phosphorus kg?1 diet. The results showed that specific growth rate and feed efficiency increased with increasing dietary available P from 0.8 to 7.4 g P kg?1. Fish body ash increased with increasing dietary available P, while moisture, protein content or energy content had no difference. Total phosphorus waste discharging (TPW) increased with increased dietary phosphorous. Plasma glucose was higher in the fish fed with 7.4 g kg?1 P. Plasma triglycerides was lower in fish fed diets containing 6.1–10.1 g kg?1 P. No significant effects were observed in plasma P and Ca (p > .05). The activities of intestinal amylase, lipase and trypsin showed no difference, while AKP and Na+, K+‐ATPase activities decreased with increasing dietary available P. In conclusion, based on the regression between specific growth rate (SGR), P retention efficiency, feed efficiency (FE) and dietary available P, the available P requirements for on‐growing gibel carp were 10.69, 8.22 and 6.72 g kg?1, respectively.  相似文献   

3.
An 11‐week growth trial was conducted to determine dietary myo‐inositol (MI) requirement for juvenile gibel carp (Carassius auratus gibelio). Myo‐inositol was supplemented to the basal diet to formulate six purified diets containing 1, 56, 107, 146, 194 and 247 mg MI kg?1 diet, respectively. Each diet was fed to triplicate groups of juvenile gibel carp (initial body weight 3.38 ± 0.27 g, mean ± SD) in a flow‐through system. The diets were randomly assigned to different fish tanks. Fish fed ≥ 107 mg MI kg?1 diet had significantly higher weight gain (WG), feed efficiency (FE) and protein efficiency ratio than those fed 1 mg MI kg?1 diet. Fish fed ≥ 56 mg MI kg?1 diet had higher feeding rate and survival compared with fish fed 1 mg MI kg?1 diet. Dietary supplemental inositol did not affect fish liver inositol concentration. Fish fed ≥ 56 mg MI kg?1 diet had higher body dry matter, crude protein and gross energy and lower hepatosomatic index than fish fed 1 mg MI kg?1 diet. Dietary inositol supplementation decreased fish body ash. Quadratic regression of weight gain indicated that the myo‐inositol requirement to maximum growth for juvenile gibel carp was 165.3 mg MI kg?1 diet.  相似文献   

4.
Daidzein is widely used in farmed animals as a dietary additive. However, limited information is available about its use in aquaculture. The effects of daidzein inclusion in the diet of gibel carp was assessed in terms of growth performance, immune response, disease resistance, antioxidant activity, hormone levels, daidzein tissue residues, as well as intestinal and liver morphology. The dietary daidzein inclusion levels were 0, 40, 200 and 400 mg kg?1 and six replicates of 30 fish were used for each group. No mortality was observed during the 80‐day feeding trial. The growth performance of experimental fish was not significantly affected by dietary daidzein supplementation. However, the non‐specific immune responses, resistance to Aeromonas hydrophila, antioxidant activities, 17β‐oestradiol level, vitellogenin concentration, gonadosomatic index (GSI) and intestinal morphology were significantly affected by dietary daidzein. A dietary dose of 400 mg kg?1 daidzein significantly decreased the GSI, increased 17β‐oestradiol and vitellogenin concentrations, and impaired the intestinal structure. The daidzein residue in muscle of gibel carp was increased by the high level (400 mg kg?1) of dietary daidzein. Equol was not detected in fish muscle among all treatments. The present study proved that 40 mg kg?1 daidzein was safe to be included in diets of gibel carp, and a safety margin of 5 folds of the use‐level (40 mg kg?1) was determined.  相似文献   

5.
A 60‐day growth experiment was conducted to investigate the effect of dietary replacement of fishmeal by Spirulina platensis on growth performance, digestion and physiological parameters in juvenile gibel carp (5.0 ± 1.0 g). Four diets were formulated to replace 0 (SP0), 50% (SP50), 75% (SP75) and 100% (SP100) of dietary fishmeal protein by S. platensis respectively. Other two diets based on SP100 were supplemented with 2% dicalcium phosphate (SP100 + P) or 0.28% coated lysine (SP100 + Lys). The results showed that no significant differences of specific growth rate (SGR), feed efficiency (FE), feeding rate (FR) and protein efficiency ratio (PER) were observed between SP0 group and the replacement groups (SP50, SP75 and SP100). FE and PER of fish‐fed SP100 + Lys diet were significantly higher than the fish‐fed SP100 diet (p < .05). Apparent digestibility coefficients (ADCs) of dry matter, protein, energy and phosphorus increased significantly with the increasing S. platensis inclusion. Meanwhile, fish from SP100 + P or SP100 + Lys group had higher ADCs of nutrients compared to the SP100 group (p < .05). Compared with SP0 diet, fish‐fed S. platensis diets had higher activities of plasma superoxide dismutase, hepatopancreas total antioxidant capacity, plasma alkaline phosphatase and plasma lysozyme, as well as the lower content of plasma malondialdehyde. The present results indicated that dietary fishmeal could be fully replaced by S. platensis without any negative effects on growth performance of gibel carp. Supplementation of lysine in the S. platensis replacement diet could further improve the feed utilization of gibel carp.  相似文献   

6.
Myxozoans usually have a complex life cycle involving indirect transmission between vertebrate and invertebrate hosts. The vertical transmission of these parasites in vertebrate hosts has not been documented so far. Here, we assessed whether the myxozoan parasite Myxobolus honghuensis is vertically transmitted in naturally infected allogynogenetic gibel carp Carassius auratus gibelio (Bloch). M. honghuensis infection of broodfish, fertilized eggs and laboratory-cultured progeny was monitored in 2018 and 2019. The presporogonic stage was microscopically observed in the pharynx of broodfish and their progeny. In situ hybridization confirmed the presence of M. honghuensis presporogonic stage in the pharynx of broodfish and progeny. Nested PCR results showed that M. honghuensis was present in tissues and eggs of broodfish, fertilized eggs and their corresponding progeny. The sequences obtained from broodfish and progeny showed 98.0−99.8% similarity with ITS-5.8S rDNA of M. honghuensis. This study provides molecular and light microscopy evidence for the transfer of M. honghuensis from broodfish to progeny via the eggs, but it is insufficient to assert that M. honghuensis can transmit vertically in naturally infected allogynogenetic gibel carp. This is the first record about vertical transfer of myxozoan in the vertebrate host.  相似文献   

7.
Interrupting quorum sensing represents a novel anti‐infective strategy to combat bacterial pathogen, and biodegradation of quorum sensing signal AHLs has been proved to be an efficient way to control pathogenic Gram‐negative bacteria in aquaculture. In this study, the effect of Bacillus firmus sw40 as efficient AHL‐degrading strain on virulence of fish pathogen Aeromonas hydrophila and disease resistance of gibel carp Carassius auratus gibelio was investigated. The results demonstrated that in vitro the B. firmus sw40 extracellular production (ECP) was able to significantly decrease protease production, haemolytic activity and biofilm formation in A. hydrophila. Dietary administration of B. firmus sw40 (109 CFU/g) for 4 weeks significantly reduced the inflammatory cytokines TNF‐1a, TNF‐2a and IFN‐γ genes expression, antioxidant parameter MDA and GSH levels in serum and increased antioxidant enzyme SOD activity. Besides, B. firmus sw40 could significantly increase the survival of gibel carp with pathogenic A. hydrophila infection.  相似文献   

8.
This experiment was conducted to study the effects of dietary carbohydrate on glucose metabolism in gibel carp (Carassius gibelio) as well to investigate if different clones had different responses to carbohydrate intake. Unselected Dongting strain (DT strain), selected gibel carp “CAS III” (A strain) and gibel carp “CAS V” (F strain) were fed with no corn starch diet (0C), 30% corn starch diet (30C) and 45% corn starch diet (45C) for 8 weeks. The results showed that selected F strain showed higher growth performance. F strain and A strain showed better control on postprandial glucose regulation by increasing plasma triglyceride, plasma cholesterol, liver and muscle glycogen contents and also enhancing glycolysis and restraining gluconeogenesis. DT strain had higher body lipid and lipid utilization. In conclusion, gibel carp could tolerate 45% dietary carbohydrate and F strain showed better growth by increasing glycolysis while decreasing glycogenesis.  相似文献   

9.
Dried distiller's grain (DDG) is considered as an alternative ingredient of dietary feed due to its high contents of protein, fibre and fat. In this study, 60 g kg‐1 of DDG was used to feed grass carp (Ctenopharyngodon idella), bluntnose black bream (Megalobrama amblycephala), gibel carp (Carassius gibelio) and black carp (Mylopharyngodon piceus) for 8 weeks, and its effect on fish production and gut allochthonous microbiota was investigated for the development of a suitable fish feed high in nutrients and low in cost for polyculture freshwater fish. DDG supplementation resulted in the less weight gain and higher feed conversion ratio of black carp (P < 0.05), but had no significant effects on other fish or parameters. PCR–denaturing gradient gel electrophoresis (DGGE) analysis indicated that all four fish species had some common and unique bacteria in their digestive tracts, and the gut microbiota of bluntnose black and gibel carp fed the control diet and DDG diets were very similar (Cs > 91%); of them, the total counts of intestinal bacteria studied by qPCR increased in grass carp (P < 0.05) and depressed in black carp (P < 0.05) when fed dietary DDG. Thus, we assumed that dietary DDG modulated production and gut microbiota of fish in a host‐specific way.  相似文献   

10.
Two 8‐week feeding trials were conducted to evaluate dietary carbohydrate utilization by omnivorous gibel carp (Carassius auratus gibelio) (2.4 ± 0.1 g) and herbivorous grass carp (Ctenopharyngodon idellus) (6.5 ± 0.1 g). Five isonitrogenous (370 g kg?1) and isolipid (70 g kg?1) diets were formulated with increasing corn starch levels (60, 140, 220, 300 and 380 g kg?1). Results showed that specific growth rate (SGR), feed efficiency (FE) and protein retention efficiency (PRE) of gibel carp significantly increased from dietary starch of 60 to 300 g kg?1 and then decreased from 300 to 380 g kg?1, but those of grass carp showed no significant differences between treatments. Independent of dietary starch levels, grass carp gained significantly higher FE and PRE than gibel carp. Feeding rate (FR) of gibel carp was significantly higher than that of grass carp. In two fish species, high dietary starch (300 and 380 g kg?1) tended to obtain higher hepatosomatic index (HSI), serum triglyceride, hepatic lipid and body lipid contents. Serum glucose concentration of grass carp was not affected, while that of gibel carp fed the starch of 300 g kg?1 diet was significantly lower than those of the fish fed other four diets (60, 140, 220 and 380 g kg?1). Grass carp showed high tolerance to dietary starch while dietary corn starch should be no more than 300 g kg?1 for gibel carp. High starch contents may cause lipid accumulation in the liver and body.  相似文献   

11.
An 8‐week growth trial investigated the effect of dietary lipid level on growth performance of a carnivorous fish, Chinese longsnout catfish (Leiocassis longirostris Günther) and an omnivorous fish, gibel carp (Carassius auratus gibelio). For each species, seven isonitrogenous semi‐purified diets (455 g kg?1 crude protein for Chinese longsnout catfish and 385 g kg?1 crude protein for gibel carp) were formulated to contain 30, 60, 90, 120, 150, 180 or 210 g kg?1 lipid. For Chinese longsnout catfish, feed intake (FI) decreased with increasing dietary lipid and there was no significant difference in feed intake from 90 to 210 g kg?1 lipid. Specific growth rate (SGR) increased with dietary lipid level (P < 0.05) and the 150 and 180 g kg?1 groups were the best. Feed conversion efficiency (FCE), protein retention efficiency (PRE) and energy retention efficiency (ERE) were higher at 180 g kg?1 lipid. For gibel carp, FI decreased with increased dietary lipid and 180 and 210 g kg?1 lipid groups showed lower values. SGR increased with dietary lipid level and the 150 and 180 g kg?1 were the best. FCE was higher at 180 g kg?1 lipid level. PRE increased with dietary lipid level and there was no significant difference in groups from 120 to 210 g kg?1 dietary lipid. ERE increased with increasing dietary lipid level, and groups fed 120, 150 and 180 g kg?1 lipid showed the highest values. In Chinese longsnout catfish, increase in dietary lipid level, resulted in increased carcass dry matter, crude protein, crude lipid and gross energy. In gibel carp, dry matter, crude protein, and crude lipid increased with dietary lipid level. Based on regression between SGR and dietary lipid, dietary lipid requirements for Chinese longsnout catfish and gibel carp were 142.6 and 140.5 g kg?1, respectively.  相似文献   

12.
A 75‐day experiment was conducted with juvenile gibel carp (Carassius auratus gibelio) (4.80 ± 0.01 g) to evaluate effects of dietary chitosan on fish growth performance, haematology, intestine morphology and immune response. Six isonitrogenous (crude protein: 383 g kg?1), isolipid (97.5 g kg?1) and isocaloric (gross energy: 16.7 kJ g?1) diets were formulated to contain 0, 1800, 4000, 7500, 10 000, 20 000 mg kg?1 chitosan, respectively. The results showed that the growth was depressed when the fish fed with 10 000 mg kg?1 chitosan. Serum cholesterol, triglyceride and low‐density lipoprotein decreased in 10 000 and 20 000 mg kg?1 chitosan. On day 75, blood leucocyte phagocytic activity respiratory burst and alternative pathway of complement haemolytic activity were enhanced in 4000 mg kg?1 chitosan. The number of goblet cell, intraepithelial lymphocyte of mid‐intestine and microvilli height of distal intestine increased at 4000 mg kg?1 dietary chitosan. Dietary chitosan modulated intestine microbiota, depressed pathogen bacteria Aeromonas veronii‐like and improved Cellulomonas hominis‐like, Bacillus oceanisediminis‐like and two uncultured bacterium‐like species on day 75. Dietary 7500 and 10 000 mg kg?1 chitosan enhanced the protection against Aeromonas hydrophila infection. In conclusion, oral administration of dietary 7500 mg kg?1 chitosan for 75 days is recommended for the survival of gibel carp.  相似文献   

13.
《水生生物资源》2003,16(5):408-415
The development of techniques for production of gynogenetic, androgenetic, polyploid, and monosex progenies in common carp (Cyprinus carpio L.) is described from a chronological perspective. Gynogenetic progenies were obtained either by suppression of the second meiotic division in eggs (meiotic gynogenesis) or by suppression of the first mitotic division in haploid embryos (mitotic gynogenesis). As a rule, gynogenetic progenies of common carp were all-female, revealing female homogamety (females—XX, males—XY) in this species. Induced gynogenesis results in increased homozygosity; the rate of increase depends on the type of gynogenesis. Inbreeding coefficient (F) for one generation of meiotic gynogenesis in common carp is about 0.6, while diploids obtained by mitotic gynogenesis are homozygous for all genes (F = 1.0). Mitotic gynogenesis was used for production of clones in common carp. In androgenetic progenies of common carp, YY males were identified, that after crossing with normal females (XX) produced all-male progenies. Triploids of common carp are characterized by a significant reduction in gonad development (especially ovaries). However, the reduction in gonad development did not result in an increase of somatic growth rate of fish. The procedure for androgen treatment to induce phenotypic sex reversal in genotypic females (XX) was elaborated. All-female progenies of common carp were produced on a large scale by crossing normal females (XX) with hormonally sex-reversed males (XX). Rearing of all-female progenies in conditions when fish normally reach sexual maturity before reaching of market size increased production yield by 7–8%. In a few cases distant hybridization resulted in polyploidy of fish without application of any physical treatment. The ability of hybrid females between crucian carp (Carassius auratus) and common carp to produce diploid (with unreduced chromosome number) gametes resulted in opportunities to produce triploid and tetraploid hybrid progenies.  相似文献   

14.
A 60‐day trial was conducted in a recirculation system to determine the responses of herbivorous grass carp (Ctenopharyngodon idellus) (0.43 g), omnivorous gibel carp (Carassius auratus gibelio CAS III) (0.46 g) and carnivorous black carp (Mylopharyngodon piceus) (0.46 g) when fed with fishmeal (FM)‐ or soybean meal (SBM)‐based diets. Two isonitrogenous (380 g kg?1 DM), isolipid (80 g kg?1 DM), isocaloric (17.75 kJ g?1) diets were formulated using FM and SBM as main protein sources. The results showed that weight gain (WG), feed efficiency (FE) and protein retention efficiency (PRE) in FM group were significantly higher than those in SBM group. Grass carp showed better utilization on SBM than other two species and presented higher WG, FE and PRE. When fed with SBM diet, intestinal chymotrypsin (CHY), lipase and trypsin (TRY) activities of gibel carp and black carp decreased while higher α‐amylase (α‐AMY) activity of grass carp increased. An enteritis‐like effect was observed in black carp and grass carp fed SBM diet. Intestine bacteria mainly belonged to Firmicutes in gibel carp and Proteobacteria in black carp. The dominant genera identified in three species were Cellulomonas, belonging to Actinobacteria. In conclusion, SBM decreased the growth of three carps. Grass carp was more adapted to plant protein.  相似文献   

15.
A 100‐day growth trial was executed to determine the dietary selenium (Se) requirement of juvenile gibel carp (Carassius auratus gibelio). Selenomethionine was supplemented to casein‐gelatin diets at 0, 0.1, 0.25, 0.5, 1.0, 2.5 and 5 mg Se kg?1, respectively. Each of these seven semi‐purified diets containing 0.34, 0.47, 0.66, 0.82, 1.23, 2.77 and 5.13 mg Se kg?1 was fed to triplicate groups of gibel carp (2.74 ± 0.02 g) in a flow‐through system. No behaviour abnormalities and no mortality were found in fish exposed to dietary Se concentrations. With the increasing dietary Se supplemented concentrations, weight gain of fish remarkably increased at the levels of ≤1 mg Se kg?1 diet and then showed no significant difference above 1 mg Se kg?1 levels. Although growth performances (weight gain, hepatosomatic index, condition factor and survival) were not impaired in gibel carp fed at above the levels of 2.5 mg Se kg?1, indicators of oxidative stress were changed significantly. Serum superoxide dismutase (SOD) activities significantly declined, hepatic glutathione peroxidase (GPx) activities significantly increased and the tissue Se concentrations significantly raised at the highest supplemented level of 5 mg Se kg?1. A clear linear relationship between Se‐depended GPx activities and hepatic Se concentrations was observed. The present results indicated that the dietary Se requirement for gibel carp is 1.18 mg Se kg?1 diet based on weight gain, GPx activities and tissue accumulation.  相似文献   

16.
Invertebrate meals (e.g. polychaetes and insects) present novel and sustainable high‐quality nutrient sources for use in fish feed formulations. To test this innovative source, an eleven‐week feeding trial was conducted evaluating the effects of replacing the fishmeal (FM) component as an example of a superior protein source (FM CTRL) with ragworm meal (RW, Nereis virens) and/or silkworm pupae (SWP, Bombyx mori) in mirror carp (Cyprinus carpio) diets. Three experimental diets with partial replacement of FM (diets: RW + FM, SWP + FM and RW + SWP + FM) were formulated. All diets were formulated to be iso‐nitrogenous, iso‐lipidic and iso‐energetic. Growth performance and feed utilization indices were assessed, and the feeding trial concluded with the analysis of haematological parameters to provide an indication of carp physiological and health status. Mean weight gain was greatest in mirror carp fed RW + FM (60.83 fish?1 day?1; P < 0.05 vs. all other diets) followed by SWP + FM (40.62 g fish?1 day?1; P < 0.05 vs. all other diets). The least weight gain was achieved in fish fed FM + SWP + RW+ and FM CTRL (34.34 and 33.96 g fish?1 day?1, respectively; not significantly different from each other). Fish fed on RW + FM diet had significantly lower plasma ammonia concentrations than any other dietary groups (P = 0.04). Mirror carp fed on SWP + FM diet (111.52 units mL?1) were observed to have a marked enhancement in alternative complement activity than FM CTRL (79.21 units mL?1, P = 0.041). Both ragworm and silkworm pupae meal present attractive sustainable functional feed component in carp diets, with benefits on enhancing growth performance and specific physiological parameters.  相似文献   

17.
Two trials were conducted to investigate protein requirements of juvenile (3.18 g in Trial 1) and on‐growing (87.1 g in Trial 2) gibel carp, Carassius auratus gibelio var. CAS III. Six isoenergetic diets containing 250–500 g kg?1 dietary protein were formulated using soy protein concentrate (SPC) and casein as protein sources. The results showed that weight gain (WG) increased when dietary protein increased from 250 to 400 g kg?1 and decreased at 400 to 500 g kg?1 CP in Trial 1, while WG increased when dietary protein increased from 250 to 350 g kg?1 and kept constant at 350 to 500 g kg?1 CP in Trial 2. With increasing dietary protein, feed conversion ratio (FCR) decreased, while protein retention efficiency (PRE) decreased in Trial 1 and was not affected in Trial 2. Apparent digestibility coefficient of protein (ADCp) increased with increasing dietary protein in two trails. Trypsin activity increased with dietary protein in the juveniles and was not affected in on‐growing fish. Hepatic alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities increased with dietary protein. Broken‐line and quadratic regression of WG estimated that dietary protein requirements for maximum growth were about 402–427 g kg?1 for the juvenile and 337–418 g kg?1 for on‐growing gibel carp.  相似文献   

18.
A ten‐week feeding trail was conducted to investigate the effects of increasing DL‐methionine (Met) supplementation on the success of fish meal (FM) replacement with plant proteins in practical diets for juvenile gibel carp, Carassius auratus gibelio. Twelve isoenergetic diets were formulated including two 150 g kg?1 FM diets (Diet 1—positive control 1 reflecting a commercial diet and Diet 2—positive control 2 reflecting a commercial diet but with balanced essential amino acid (EAA) profile) and ten 50 g kg?1 FM diets (negative controls) supplemented with graded levels (0–3.0 g kg?1) of DL‐Met (Diets 3–12). Each diet was fed to triplicate groups of gibel carp, near satiation four times daily for 10 weeks. Diet 2 with balanced EAA profile produced better final weight, specific growth rate (SGR) and feed conversion ratio (FCR) than the negative control diet containing no supplemental Met (Diet 3), but did not significantly differ from Diet 1. However, DL‐Met supplementation (0.5–3.0 g kg?1) in the negative control diets (Diets 4–12) produced growth performances similar to those fed the positive control diets (Diets 1 and 2). Based on quadratic regression analysis, the optimal dietary Met level with 5.2 g kg?1 of dietary cysteine (Cys) was found to be 7.1 g kg?1 dry diet for SGR and FCR. The corresponding total sulphur amino acid requirements (Met + Cys) of this species were calculated to be 12.3 g kg?1 dry diet for SGR and FCR. DL‐Met supplementation in 50 g kg?1 FM diets showed a decreasing trend in plasma cholesterol contents (p < .05). No significant differences were observed in whole‐body composition, plasma protein, triglyceride and free EAA contents among dietary treatments, while plasma aspartate transaminase, albumin and ammonia contents were significantly influenced by dietary Met levels. Juvenile gibel carp grew equally well on 150 g kg?1 FM diet or 50 g kg?1 FM diets balanced for EAA profile with supplemental amino acids. The results of this study overall indicate that balancing dietary amino acid levels with DL‐Met supplementation is a key strategy in successfully reducing FM levels in the diets of gibel carp.  相似文献   

19.
This study evaluated the growth and immune response of gibel carp (Carassius auratus gibelio) cultured under no feed addition biofloc technology (BFT) system at different total suspended solid (TSS) concentrations (10, 300, 600, 800 and 1,000 mg/L for group BF0‐NF, BF300‐NF, BF600‐NF, BF800‐NF and BF1000‐NF) for 30 days. The results demonstrated that bioflocs contained rich nutrients, and gibel carp eaten bioflocs showed higher weight gain, specific growth and survival. Digestive enzyme activities such as pepsin and amylase increased significantly in BF300/600/800/1000‐NF groups than those in BF0‐NF group. Antioxidant response including superoxide dismutase and total antioxidant capacity in serum and skin mucus was also enhanced significantly (p < .05). In addition, six immune‐related genes were examined by RT‐qPCR. Compared with BF0‐NF group, expression levels of immune genes intelectin (ITLN), dual specificity phosphatase 1 (DUSP 1), keratin 8 (KRT 8), myeloid‐specific‐peroxidase (MPO), c‐type lysozyme (c‐lys) and interleukin‐11 (IL‐11) were up‐regulated by 78.1‐, 23.9‐, 13.8‐, 138.8‐, 401.8‐ and 91.1‐fold, respectively. The highest expression values were observed at TSS of 600–800 mg/L. This study suggested that bioflocs can be uptaken by gibel carp as a food source, and have a potential to be used as a supplemental food for aquaculture.  相似文献   

20.
The nutritional function of monosaccharides, disaccharides and polysaccharides for omnivorous gibel carp and carnivorous Chinese longsnout catfish were investigated and the ability of these two species to utilize carbohydrates was compared. For each species, triplicate groups of fish were assigned to each of five groups of isoenergetic and isonitrogenous experimental diets with different carbohydrate sources: glucose, sucrose, dextrin, soluble starch (acid‐modified starch) and α‐cellulose. The carbohydrates were included at 60 g kg?1 in Chinese longsnout catfish diets and at 200 g kg?1 in gibel carp diets. A growth trial was carried out in a recirculation system at 27.8 ± 1.9 °C for 8 weeks. The results showed that fish with different food habits showed difference in the utilization of carbohydrate sources. For gibel carp, better specific growth rate (SGR) and feed efficiency (FE) were observed in fish fed diets containing soluble starch and cellulose, but for Chinese longsnout catfish, better SGR and FE were observed in fish fed diets containing dextrin and sucrose. Apparent digestibility coefficient of dry matter (ADCd) and apparent digestibility coefficient of energy (ADCe) were significantly affected by dietary carbohydrate sources in gibel carp. ADCd and ADCe significantly decreased as dietary carbohydrate complexity increased in Chinese longsnout catfish except that glucose diet had medium ADCd and ADCe. In both species, no significant difference of apparent digestibility coefficient of protein was observed between different carbohydrate sources. Dietary carbohydrate sources significantly affected body composition, and liver phosphoenolpyruvate carboxykinase (PEPCK), pyruvate kinase (PK), glucose 6‐phosphate dehydrogenase (G6PD) and malic enzyme (ME) activities also varied according to dietary carbohydrate complexity. Fish with different food habits showed different abilities to synthesize liver glycogen, and the liver glycogen content in gibel carp was significantly higher than in Chinese longsnout catfish. The influence of carbohydrate source on gluconeogenesis and lipogenesis was also different in the two fish species.  相似文献   

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