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1.
Juvenile mirror carp were fed with five different diets containing 303, 322, 341, 361 and 379 g kg?1 protein and reared at three different water temperatures (18, 23 and 28 °C) for 60 days. We investigated the insulin‐like growth factor I (IGF‐I) mRNA expression, growth performance and the relationship between IGF‐I mRNA expression and the growth performance. The results indicated that the IGF‐I mRNA expression, final body weight, specific growth rate (SGR) and feed efficiency (FE) were enhanced significantly with increasing dietary protein levels (P < 0.05), whereas the protein efficiency ratio, hepatosomatic index (HSI) and viscerosomatic index (VSI) were decreased. Moreover, the IGF‐I mRNA expression, final body weight and SGR were increased significantly with temperature, whereas the HSI and VSI indices were decreased significantly with temperature. Correlation analysis showed that the IGF‐I mRNA expression levels in the brain and liver were positively related to the SGR and FE growth indices (P < 0.01). Finally, the optimal protein requirements for fish growth in different seasons were determined based on the values of SGR and FE, that is 343–348 g kg?1 protein at 18 °C, 354–352 g kg?1 at 23 °C and 371–362 g kg?1 at 28 °C. In this way, we can adjust the dietary protein levels according to culture temperature to reduce any negative impacts on dietary costs and environmental pollution.  相似文献   

2.
Insulin‐like growth factor‐1 (IGF‐1), somatolactin and leptin are involved in growth regulation and energy metabolism in fish. We herein focused on serum IGF‐1 concentration analysed by enzyme‐linked immunosorbent assay in restrictively fed rainbow trout (Oncorhynchus mykiss). The animals were fed a high‐fat/low‐protein diet at daily feed increases (DFI) ranging from 0.5% to 2% of initial body weight (IBW), starting either at 62 or 176 g IBW. In selected groups, growth hormone receptor 1 (GHR1) and leptin mRNA were quantified in liver, and GHR1 mRNA also in visceral adipose tissue. Serum IGF‐1 concentrations in both IBW groups were highest at 2% and 1% DFI and were nonlinearly decreasing with reduced DFI. The low‐IBW groups had mostly lower IGF‐1 concentrations than the high‐IBW groups. Leptin and GHR1 mRNA decreased with feeding intensity in liver, but GHR1 mRNA increased in adipose tissue. IGF‐1 is related to growth and may help to mitigate oxidative stress in consequence of lipid mobilization during restrictive feeding. IGF‐1 secretion associated with stress response in addition to its function in growth and energy metabolism seemed to reach a point of inflection at DFI 1%. Leptin and GHR1 might be linked to lipid metabolism and free fatty acid partitioning towards liver.  相似文献   

3.
This study was conducted to investigate the effect of fish protein hydrolysate on growth performance, insulin‐like growth factor I (IGF‐I) levels and the expression levels of liver IGF‐I mRNA in juvenile Japanese flounder (Paralichthys olivaceus). Fish hydrolysate was produced by enzymatic (alcalase and flavourzyme) treatment and size‐fractionated by ultrafiltration. The permeate after ultrafiltration (UF) and the non‐ultrafiltered fish hydrolysate were tested as feed ingredients using high plant protein diets. Fish meal was used in the control diet (FM). The feeding trial lasted for 60 days, and fish fed with 37 g kg?1 UF showed the best growth, feed efficiency, digestibility and protein utilization. Plasma IGF‐I level was examined with radioimmunoassay, and the expression levels of liver IGF‐I mRNA were evaluated using real‐time PCR normalized against the 18S rRNA gene. Plasma IGF‐I levels were significantly increased by inclusion of fish protein hydrolysate. Liver IGF‐I mRNA expression was significantly higher in fish fed with 37 g kg?1 UF diet than fish fed with control diet. The results indicated that small molecular weight compounds from fish protein hydrolysate showed a positive effect on growth and feed utilization in juvenile Japanese flounder. Dietary fish protein hydrolysate could improve plasma IGF‐I levels and liver IGF‐I mRNA expression in Japanese flounder.  相似文献   

4.
A 10‐week feeding experiment in indoor flow‐through seawater system was conducted to investigate the effects of dietary krill hydrolysate on the expression of growth‐related genes in juvenile turbot (Scophthalmus maximus L.; initial body weight 9.45 ± 0.01 g). Three isonitrogenous and isolipidic experimental diets containing high plant protein were formulated to contain 0 (control), 50 g/kg (LKH) and 100 g/kg (HKH) krill protein hydrolysate (KH) to replace fishmeal, respectively. Triplicate groups of 30 fish were fed for 10 weeks to apparent satiation twice daily. At the end of the feeding trial, the mRNA expressions of insulin‐like growth factor (IGF‐1) gene in liver, peptide transporters (PepT1) gene in pyloric caeca and proximal intestine and neuropeptide Y (NPY) gene in brain in all groups were determined. IGF‐1, PepT1 and NPY expression levels in HKH group were significantly increased compared with those of LKH and control (p < 0.05), which was consistent with the SGR, feed efficiency, PER and PPV. These results indicated that dietary 100 g/kg krill hydrolysate could improve growth performance and upregulate the mRNA expression of IGF‐1, PepT1 and NPY genes in juvenile turbot.  相似文献   

5.
An 8‐week growth trial was conducted to investigate the effects of dietary Arg levels (7.6, 12.3, 17.9, 22.4 and 28.6 g/kg diet) on growth performance, hepatopancreatic antioxidant capacity, intestinal morphology and growth‐related gene expressions of juvenile grass carp (Ctenopharyngodon idellus). The results showed that SGR in Arg22 and Arg28 groups was lower than in Arg12 and Arg17 groups (p < 0.05). Serum NO content in Arg7 group was lower than other groups. Hepatopancreatic GSH‐Px activity was higher in Arg17 group than in Arg7 group, while MDA content showed the opposite trend. Hepatopancreatic IGF‐1 expression tended to increase with Arg from 7.6 to 22.4 g/kg and then decreased in Arg28 group (p < 0.05), while IGFBP‐1 expression increased with Arg level. Muscle mRNA expressions of TOR and S6K1 showed quadratic trends as dietary Arg level increased, which were higher in Arg17 group than in Arg22 and Arg28 groups (p < 0.05). Higher mRNA expression levels of y+LAT1, y+LAT2 and PepT1, as well as higher villus height and villus width in foregut, were all observed in Arg17 group. The optimal dietary Arg level based on SGR by the quadratic model was 15.3 g/kg diet for juvenile grass carp, corresponding to 54.7 g/kg dietary protein.  相似文献   

6.
A 12‐week feeding trial was conducted using Nile tilapia, Oreochromis niloticus (L.) to evaluate the interactive effects of fishmeal replacement and salinity on growth, feed utilization efficiencies and relative expression of growth related genes. Two iso‐nitrogenous and iso‐energetic diets were prepared (32% protein). The control diet included 15% fishmeal (FM diet) and fishmeal component in non‐fishmeal diet (NFM) was eliminated by a mixture of poultry by‐product meal, high protein distillers dried grains and distillers dried grains with soluble. The NFM diet was supplemented with DL‐methionine and L‐lysine. Duplicated group of fish with initial mean weight of 6 g, reared in four salinity levels (0, 4, 8 and 12 g/L) were fed one of the two diets twice a day to near satiety. At the end of the experiment, growth, feed utilization efficiency and expression of growth related genes were compared. The specific growth rate (SGR), mean feed intake (MFI) and feed conversion ratio (FCR) were not affected by the diets while salinity effects were significant. The fish in the 4 g/L salinity showed the highest SGR and MFI while fish in the 0 g/L treatment showed the lowest FCR. Relative expression of hepatic IGF‐I and IGF‐II was regulated by salinity but not by the diet. Expression of growth hormone receptor gene was not affected by either diet or salinity. The present findings provide evidence for the possibility of total fishmeal replacement in saline waters (0–12 g/L) without compromising growth, feed utilization and body composition of Nile tilapia.  相似文献   

7.
This experiment was conducted to evaluate the feasibility of gamma‐irradiated soybean meal (SBM) as a dietary ingredient on the performance, body composition, and digestive enzyme activity of Caspian brown trout, Salmo trutta caspius, juveniles. Five isonitrogenous and isoenergetic diets were formulated, in which fish meal was replaced by untreated (untreated SBM), gamma‐ray irradiated at 15 (15ISBM) and 30 (30ISBM) kGy, fermented (FSBM), fermented 15 KGy irradiated soybean meal (FISBM), respectively. Juvenile fish (2.1 ± 0.3 g) were fed with the test diets for 6 wk. Final body weight was significantly affected by dietary SBM treatment with highest values in fish fed FISBM and FSBM (P < 0.05). There were no significant differences in hepatosomatic and visceral indexes, condition factor, and survival among experimental groups (P > 0.05). The carcass proximate composition of lipid and protein in Caspian brown trout in FSBM and FISBM groups was higher than that of other groups. Levels of most whole‐body amino acids were not significantly different among Caspian brown trout fed the five diets. Results of this experiment showed that replacing SBM with FSBM and FISBM in the diet significantly increased the activities of proteolytic enzymes activities (P < 0.05). However, no significant differences were observed in both amylase and lipase activities among dietary treatments. Results of this study indicated that the level of gamma radiation used did not work but fermentation of SBM did increase some growth parameters of Caspian brown trout.  相似文献   

8.
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9.
Many fish species display compensatory growth (CG), a phenomenon by which fasted fish grow faster during refeeding. However, most studies use a group‐housed fish approach that could be problematic in social fish when interaction between individuals is not considered or eliminated. Additionally, the growth hormone (GH)/insulin‐like growth factors’ (IGF‐1 and IGF‐2) axis is implicated in postnatal growth in vertebrates, but its relevance in CG is not fully understood. Thus, the aim of this work was to determine whether CG occurs in a social fish, Cichlasoma dimerus, using an individually held fish approach and secondly, to evaluate the GH/IGFs expression profile during refeeding by 3 days and 3 weeks. C. dimerus showed partial CG. The feed conversion efficiency (FCE) was higher in three‐day‐refed fish, which presented higher GH plasma and mRNA levels than controls but shown no differences in liver and muscle GH receptors (GHR1 and GHR2) and IGFs mRNA levels. Surprisingly, three‐week‐refed fish exhibited GHR1 and IGF‐2 increments, but a reduction in GHR2 expression in muscle. These results show a strong association between GH levels, growth rate and FCE during refeeding, and a long‐lasting effect of refeeding on muscular expression of GHRs and IGF‐2.  相似文献   

10.
An 8‐week feeding trial was conducted to evaluate the dietary arginine requirement of juvenile hybrid sturgeon. Seven isonitrogenous and isolipidic diets were formulated to contain graded levels of dietary arginine ranging from 1.74% to 3.54% (dry weight). The results indicated that the fish fed with 1.76% arginine diet had lower specific growth rate (SGR) and feed efficiency ratio (FER) than the fish fed the 2.64% to 3.24% arginine diets (p < .05), and the fish fed the 2.64% arginine diet presented the highest SGR. The fish fed with 1.76% arginine diet had lower whole‐body crude protein content than the fish fed the 2.64% or 2.93% arginine diets (p < .05). Compared with the 1.76% arginine diet, 2.36% to 2.93% arginine diets significantly increased the total amino acid (TAA) concentration and total nonessential amino acid (TNEAA) of carcasses. The fish fed with 1.76% arginine diet had lower activity of nitric oxide synthase (T‐NOS) and content of nitric oxide (NO) than the fish fed the 2.05% to 2.93% arginine diets in the liver. The fish fed with 1.76%, 2.05% or 2.36% arginine diets had lower gene expression of growth hormone (GH) and insulin‐like growth factor I (IGF‐I) in the liver than the fish fed the 2.64% to 3.53% arginine diets in the liver (p < .05). A broken‐line analysis between SGR against the dietary arginine levels provided estimates for the optimal dietary arginine requirement of 2.47% corresponding to 6.18% of the dietary protein on a dry weight basis.  相似文献   

11.
A 56‐d growth trial was conducted to evaluate the growth performance, lipid deposition, and antioxidative capacity of juvenile scaleless carp, Gymnocypris przewalskii, on Qinghai‐Tibetan Plateau. One‐year‐old juveniles (initial weight: 15.99 ± 0.02 g) were fed practical diets with different lipid levels of 4, 5.5, 7, 8.5, and 10%, respectively. Results showed that the best specific growth rate (SGR), feed conversion rate, and total antioxidative capacity (T‐AOC) in hepatopancreas were observed in fish fed the diet with 7% lipid level. Fish fed with high lipid diets (8.5 and 10%) had significantly higher condition factor and viscerosomatic index as well as lipid in muscle, intestine, mesenteric fat tissue, and whole body. Highest level of hepatopancreas lipase and lipoprotein lipases activities as well as malondialdehyde content and the lowest level of feed intake and T‐AOC content in hepatopancreas and intestine were also observed in fish fed with high lipid diets (8.5 and 10%) (P < 0.05). In conclusion, based on SGR and hepatopancreas T‐AOC content, dietary lipid requirement of juvenile G. przewalskii was estimated to be 7.35 and 7.39%, respectively.  相似文献   

12.
The imbalance of fish oil (FO) supply and demand has motivated efforts to identify an alternative for aqua feed. An 8‐week feeding trial was conducted to evaluate the effects of dietary fish oil partial replacement with mixed oil from linseed and lard (1:1) on growth, body composition and immunity when the N3 long‐chain polyunsaturated fatty acid (N3 LC‐PUFAs) requirement is met for Nibea albiflora. Two types of experimental diets were formulated with 100% fish oil (FO) or 69% mixed oil (Mix). The results indicated that the Mix diet significantly improved the specific growth rate (SGR), weight gain (WG), feed efficiency ratio (FER), muscle tissue growth hormone receptor (GHR), insulin‐like growth factor 1 (IGF1) and insulin‐like growth factor 1 receptor (IGF1R) gene expression of the yellow drum (p < .05). No significant difference in the survival rate (SR), feed intake (FI), hepatosomatic index (HSI), viscerosomatic index (VSI), condition factor (CF), N3 PUFA percentage, liver antioxidant enzyme activities or pro‐inflammatory gene expression was observed between the two treatments. Therefore, terrestrial blend lipid from linseed and lard could be used as an alternative for dietary fish oil without compromising growth performance and immunity for the juvenile yellow drum.  相似文献   

13.
One thousand and eighty rohu fingerlings with an average size of 8.5 ± 0.5 g were randomly distributed in 6 distinct experimental groups in triplicates, where the first three groups were exposed to high stocking density (HSD; 20 nos/ 75 L water) with restricted feeding (RF), viz. THR0 (HSD, RF, 0% nutraceutical), THR1 (HSD, RF, 0.1% nutraceutical) and THR5 (HSD, RF, 0.5% nutraceutical), and second three groups were exposed to normal stocking density (NSD; 10 nos /75 L water) with satiation feeding (SF) and designated as TNS0 (NSD, SF, 0% nutraceutical), TNS1 (NSD, SF, 0.1% nutraceutical) and TNS5 (NSD, SF, 0.5% nutraceutical). The weight gain (WG) %, specific growth rate (SGR), protein efficiency ratio (PER) and IGF‐1 expression were significantly lower, whereas feed conversion ratio (FCR), serum superoxide dismutase (SOD) and catalase activities were significantly higher in fish exposed to HSD with RF at monthly sampling. Feeding of 0.1% dietary nutraceutical resulted in a significantly higher WG%, SGR, PER and IGF‐1 expression and lower FCR, SOD and catalase activities at the end of the third and fourth month of feeding in HSD with RF groups. The present study concluded that 3‐month feeding of 0.1% nutraceutical could improve growth and reduce stress in fish.  相似文献   

14.
The effects on growth and body composition that result from tuna byproduct meal (TBM) substituted for fish meal in the diet of juvenile abalone, Haliotis discus, were determined. One thousand two hundred sixty juvenile abalone were randomly distributed into 18 70‐L plastic rectangular containers. Six experimental diets were prepared in triplicate. The TBM0 diet included 28% fish meal and 13% soybean meal as the protein source. Twenty‐five, 50, 75, and 100% of the fish meal were substituted with TBM. Finally, salted sea tangle was prepared. The essential amino acids, such as isoleucine, lysine, and valine, tended to decrease with the dietary substitution of TBM for fish meal in the experimental diets. The weight gain and specific growth rate (SGR) of abalone that were fed the TBM25 diet were higher than those of abalone that were fed the other diets. The crude protein content of the soft body of the abalone linearly decreased with the dietary substitution of TBM for fish meal. In conclusion, as much as 75% of the fish meal in the diet of abalone can be replaced with TBM without retardation in weight gain and SGR of the abalone when 28% fish meal was included.  相似文献   

15.
Responses of compensatory growth to high temperature and feed restriction in juvenile tongue sole, Cynoglossus semilaevis (Güther, 1873), were investigated during a 56‐days experiment. Fish were divided into seven groups including three high‐temperature treatments which were reared at 28°C for 1, 2 and 3 weeks, respectively, then returned to 22°C (recorded as T1, T2 and T3), three feed‐restricted treatments which were fed 25% satiation for 1, 2 and 3 weeks, respectively, then fed ad libitum (recorded as R1, R2 and R3) and a control (continuously reared at 22°C). The results showed that juvenile tongue sole exposed to thermal stress for 1 week exhibited overcompensatory growth. However, complete compensation occurred in T2, T3 and R1 fish, while partial compensation occurred in R2 and R3 fish. The body composition and energy content of fish were not significantly different among all treatments (P > 0.05). The specific growth rate and feed efficiency of fish in T1 were significantly higher than other treatments during the whole experiment period (P < 0.05). Higher feed efficiency and apparent digestion rate during recovery might account for the compensatory growth in tongue sole in the present study. Hyperphagia played an important role in compensatory growth for feed‐restricted fish, but was not involved in the compensatory response in thermal stressed fish in the present study. The results from the present study suggested that a suitable thermal stress could be more feasible to elicit compensatory growth than feed restriction in juvenile tongue sole.  相似文献   

16.
A 21‐day growth trial was undertaken to investigate the effect of water temperature (25, 28, 31, 34, 37 °C) on growth, feed utilization and energy budget of juvenile Nile tilapia (Oreochromis niloticus) (initial body weight around 12 g) with four replicates at each temperature. Feed intake energy (IE), recovered energy (RE), faecal energy (FE), excretory energy (UE + ZE) and heat energy (HE) were calculated to obtain the energy budget. The results showed that feeding rate and ammonia excretion were not significantly affected by water temperature. Specific growth rate in wet weight (SGRw) and FE was significantly lower in the fish reared at 37 °C while no significant difference was observed between the fish reared at 25–34 °C. Protein retention efficiency was highest at 28 °C and lowest at 37 °C. The proportion of IE channelled into RE and UE + ZE was lower while those lost in HE was higher in the fish reared at 37 °C. The optimal growth temperature was estimated as 30.1 °C based on the regression of SGR and water temperature. Energy budget at maximum growth (34 °C) was: 100 IE = 27.0 RE + 1.1 (ZE + UE) + 10.6 FE + 59.2 HE. HE accounted for 69.3% and RE for 30.7% of metabolizable energy.  相似文献   

17.
A feeding trial was conducted to determine the amount of soybean meal (SBM) that could replace fish meal (FM) without compromising growth and health of Asian red‐tailed catfish (Hemibagrus wyckioides). Five isonitrogenous and isoenergetic diets (S0, S15, S30, S45 and S60) were formulated with SBM to replace 0%, 15%, 30%, 45% and 60% of FM. The replacement level up to 30% improved daily growth coefficient, plasma adenosine monophosphate deaminase (AMPD) and alanine aminotransferase (ALT) activities and IgM content, and hepatic ALT, aspartate aminotransferase (AST) and glutathione reductase activities, whereas these were depressed by a further inclusion. The highest protein efficiency ratio and lowest feed conversion ratio were observed in fish fed the S15 diet. Replacement of FM with SBM generally decreased plasma insulin and insulin‐like growth factor 1 (IGF‐1) contents and hepatic catalase activity, whereas no significant differences were observed among fish fed the S0, S15 and S30 diets. In contrast, replacing FM with SBM generally increased blood urea nitrogen content, and that was higher in fish fed the S60 diet compared to fish fed the S0 diet. The highest growth hormone (GH) and glutamate dehydrogenase (GDH) activities were observed in fish fed the S30 diet. Fish fed the S30 and S45 diets exhibited the highest hepatic AMPD, GDH, IGF‐1 and target of rapamycin mRNA levels and muscle AMPD and GDH mRNA levels, whereas those were lowest in fish fed the S60 diet. These results indicate that under the reported conditions SBM may be included in the diet up to 222 g/kg as a substitute for FM, replacing about 30% of FM protein in juvenile H. wyckioides.  相似文献   

18.
Ocean acidification, resulted from high level of carbon dioxide (CO2) dissolved in seawater, may disturb the physiology of fish in many ways. However, it is unclear how acidification may impact the growth rate and/or growth hormones of marine fish. In this study, we exposed juvenile orange‐spotted groupers (Epinephelus coioides) to seawater of different levels of acidification: a condition predicted by the Intergovernmental Panel on Climate Change (pH 7.8–8.0), and a more extreme condition (pH 7.4–7.6) that may occur in coastal waters in the near future. After 6 weeks of exposure, the growth rates of fish in pH 7.4–7.6 were less than those raised in control water (pH 8.1–8.3). Furthermore, exposure at pH 7.4–7.6 increased blood pCO2 and HCO3? significantly; exposure at pH 7.8–8.0, meanwhile, did not affect acid–base chemistry. Moreover, exposure to pH 7.4–7.6 resulted in lower levels of hepatic igf1 (insulin‐like growth factor I) mRNA, but did not affect levels of pituitary gh (growth hormone) or hypothalamus psst2 and psst3 (prepro‐somatostatin II and III). The results show that highly acidified seawater suppresses growth of juvenile grouper, which may be a consequence of reduced levels of IGF‐1, but not due to diminished growth hormone release.  相似文献   

19.
A feeding trial was conducted to evaluate the results of replacing soybean meal (SBM) with other blend plant protein (BP) (rapeseed meal, cottonseed meal and peanut meal) sources on growth, fish body composition, biochemical parameters, non‐specific immune index and gene expression of growth hormone/insulin‐like growth factor‐1 in Yellow River carp Cyprinus carpio. The results showed that the 600 g/kg replacement with BP in diet did not affect the growth performance of Yellow River carp, but the 800 g/kg SBM replacement diet could depress the growth of fish (p < .05). The 800 g/kg SBM replacement diet significantly impacted the superoxide dismutase, malondialdehyde contents, lysozyme, alanine aminotransferase and aspartate aminotransferase activities (p < .05). Fish fed 800 g/kg SBM replacement diet showed lowest insulin‐like growth factor 1 and highest growth hormone level than that of other diets (p < .05). Both gene expression levels of GH and IGF‐I in hepatic showed significant difference among dietary treatments (p < .05), and the lowest GH and IGF‐I mRNA level in liver were found in fish fed 800 g/kg SBM replacement diet (p < .05). In conclusion, no more than 600 g/kg SBM could be replaced by BP in diet of Yellow River carp without adverse effects on the growth performance. However, 800 g/kg SBM replacement with BP in diet inhibited the growth performance, affected some blood parameters and immune response index, and down‐regulated GH and IGF‐1 gene expression of liver in Yellow River carp. Further, GH level in serum was negatively correlated with GH mRNA level in liver; meanwhile, serum concentrations of IGF‐I were positively correlated with hepatic IGF‐I mRNA expressions.  相似文献   

20.
Growth and survival of hatchery‐bred Asian catfish, Clarias macrocephalus (Günther), fry reared at different stocking densities in net cages suspended in tanks and ponds were measured. The stocking densities used were 285, 571 and 1143 fry m?3 in tanks and 114, 228 and 457 fry m?3 in ponds. Fish were fed a formulated diet throughout the 28‐day rearing period. Generally, fish reared in cages in ponds grew faster, with a specific growth rate (SGR) range of 10.3–14.6% day?1, than those in cages suspended in tanks (SGR range 9–11.3% day?1). This could be attributed to the presence of natural zooplankton (copepods and cladocerans) in the pond throughout the culture period, which served as additional food sources for catfish juveniles. In both scenarios, the fish reared at lower densities had significantly higher SGR than fish reared at higher densities. In the pond, the SGR of fish held at 228 and 457 m?3 were similar to each other but were significantly lower than those of fish held at 114 m?3. The zooplankton in ponds consisted mostly of copepods and cladocerans, in contrast to tanks, in which rotifers were more predominant. Per cent survival ranged from 85% to 89% in tanks and from 78% to 87% in ponds and did not differ significantly among stocking densities and between rearing systems. In conclusion, catfish nursery in cages suspended in tanks and ponds is density dependent. Catfish fry reared at 285 m?3 in tanks and at 114 m?3 in ponds had significantly faster growth rates than fish reared at higher densities. However, the desired fingerling size of 3–4 cm total length for stocking in grow‐out culture can still be attained at stocking densities of 457 m?3 in nursery pond and 571 m?3 in tanks.  相似文献   

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