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1.
Four diets (T0–T3) were formulated reducing the fishmeal (Indian) component by 100 g kg–1 from 300 to 0 g kg–1 and including proportionately increasing quantities of maize. Diets were fed for 120 days at 50 g kg–1 body weight to triplicate groups of common carp (av. wt. 2.11–2.18 g) stocked at 1 m–2 in mud bottomed cement tanks (18 m2), fertilized with poultry manure. Fish growth, SGR and FCR in the different treatments were statistically not significantly different ( P  > 0.05). PER was lowest for the 300 g fishmeal kg–1 diet treatment (diet T0), increasing with decrease in dietary fishmeal content (diets T1–T3). Fish survival ranged from 96.29 to 100%. Diets influenced carcass composition and digestive enzyme activity. A significant increase in lipid deposition was recorded with increasing dietary carbohydrate content. Amylase, protease and lipase activities were higher in fish fed with diets T2 and T3. The protein sparing effect of dietary carbohydrate and the economic implication of eliminating fishmeal from the diet are discussed.  相似文献   

2.
Six isonitrogenous (350 g kg−1 crude protein) and isoenergetic (17573 kJ kg−1) experimental diets incorporating raw and fermented sesame ( Seasamum indicum ) seed meal at 200, 300, and 400 g kg−1 into a fishmeal based diet were fed to rohu Labeo rohita fingerlings for 60 days and the growth performance and feed utilization efficiency of the fish was studied. The antinutritional factor phytic acid, from raw sesame seed meal, could be reduced below detection limit by fermentation with lactic acid bacteria ( Lactobacillus acidophilus ). Fermentation of the oilseed meal resulted in reduction of the tannin content from 20 to 10 g kg−1. In terms of growth response, feed conversion ratio and protein efficiency ratio, a diet containing 400 g kg−1 fermented sesame seed meal resulted in a significantly ( P  < 0.01) best fish performance. In general, growth and feed utilization efficiencies of fish fed fermented sesame seed meal diets were superior to those fed raw oilseed meal diets. Apparent protein digestibility (APD) values decreased with increasing levels of raw oilseed meal. APD was, however, significantly ( P  < 0.01) higher at all levels of incorporation of fermented sesame seed meal, while diets containing raw oilseed meal resulted in poor protein and lipid digestibility. Carcass protein and lipid contents of fish fed fermented sesame seed meal diets increased with increasing level of incorporation, being highest with 400 g kg−1 fermented oilseed meal-containing diet. The results showed that sesame seed meal may be incorporated in carp diets up to 200 g kg−1 and 400 g kg−1 in raw and treated (fermented) forms respectively.  相似文献   

3.
Five iso-nitrogenous (300 g crude protein kg−1 diet) semi-purified diets with graded levels of carbohydrate at 220 (D-1), 260 (D-2), 300 (D-3), 340 (D-4) and 380 (D-5) g kg−1 diet were fed ad libitum to Puntius gonionotus fingerlings (average weight 0.59±0.01 g) in triplicate groups (20 fish replicate−1) for a period of 90 days to determine the effect of the dietary carbohydrate level on the growth, nutrient utilization, digestibility, gut enzyme activity and whole-body composition of fish. Fifteen flow-through cement tanks of 100 L capacity with a flow rate of 0.5 L min−1 were used for rearing the fish. The maximum weight gain, specific growth rate, protein efficiency ratio, RNA:DNA ratio, whole-body protein content, protease activity, protein and energy digestibility and minimum feed conversion ratio (FCR) were found in the D-2 group fed with 260 g carbohydrate kg−1 diet. The highest protein and energy retention was also recorded in the same group. However, from the second-order polynomial regression analysis, the maximum growth and nutrient utilization of P. gonionotus fingerlings was 291.3–298.3 g carbohydrate kg−1 diet at a dietary protein level of 300 g kg−1 with a protein/energy (P/E) ratio of 20.58 −20.75 g protein MJ−1.  相似文献   

4.
An 8-week feeding trial was conducted in flow through system to examine the effects of dietary supplementation of lysine and methionine on growth, nutrient utilization, haemato-biochemical status and carcass compositions in Indian major carp, rohu, Labeo rohita fingerlings (average weight 6.32 ± 0.06 g). Four experimental soy protein-based diets D 0 (without lysine or methionine supplementation), D 1 (lysine supplementation alone), D 2 (methionine supplementation alone) and D3 (both lysine and methionine supplementation) were fed to triplicate groups. l -Lysine and dl -methionine were added to the diets containing 550 g kg−1 soybean meals at 4 and 7 g kg−1 of dry diet respectively. Significant higher weight gain, specific growth rate (SGR), protein efficiency ratio (PER), dry matter retention, nitrogen retention, total ash retention, whole carcass protein, haemoglobin concentration, haematocrit value, total erythrocytic count, total leucocytic count, plasma glucose and plasma total protein and lower FCR, per cent lipid retention and whole body moisture content were observed in fish fed soya protein-based diet supplemented with both lysine and methionine than that of fish of other dietary groups at the end of 8 weeks feeding trial. Although fish fed diet supplemented with either methionine or lysine did not show any significant differences of growth performances, feed utilization, carcass composition and haemato-biochemical status, fish of both of these dietary groups showed significantly better growth performances, feed utilization, carcass composition and haemato-biochemical status than that of fish fed diet without lysine and methionine supplementation.  相似文献   

5.
The efficacy of pharaoh cuttlefish ( Sepia pharaonis Ehrenberg, 1831) liver lipid in the feed for juveniles of giant freshwater prawn Macrobrachium rosenbergii (De Man 1879) was tested by feeding five experimental diets prepared using clam meat, groundnut oil cake, wheat bran, tapioca powder, vitamin–mineral mixture and cellulose powder as the major ingredients. The test diets T1, T2, T3, T4 and T5, containing five levels (1, 2, 3, 4 and 5%, respectively) of lipid, extracted from the liver of pharaoh cuttlefish, were fed to 30-day-old prawn juveniles for 60 days, in triplicates and compared against a control. Analysis of variance of the growth parameters showed that the juveniles fed with T2, containing 2% cuttlefish liver lipid with a total lipid content of 9.85% and lipid–carbohydrate ratio of 1 : 3.8, showed significantly better growth ( P  < 0.05) with the highest weight gain of 118%, greatest food conversion and protein utilization efficiency, and the highest body protein content, although the survival rates remained unaffected among treatments. Growth of the juveniles, however, declined at lipid levels >2%. Addition of cuttlefish liver lipid led to an increase of ω-3 and ω-6 fatty acids in T2, the proportion of ω-6 being higher than the former. The crude lipid content of the body of test animals also increased with the increase in dietary lipid from 1.51% in T1 to 3.27% in T5. The present study indicates that cuttlefish liver lipid can be successfully used as a substitute for conventional lipid sources in rearing juveniles of giant freshwater prawn, an eco-friendly practice in recycling cuttlefish waste – a discarded fishery by-product.  相似文献   

6.
This study was conducted to determine the effect of phytase on apparent dry matter (DM), crude protein and phosphorus (P) digestibility of four plant feedstuffs (isolated soya protein, ISP; soyabean meal, SBM; corn gluten meal, CGM and wheat middlings, WM) fed to striped bass Morone saxatilis . One reference diet was formulated based solely on animal feed ingredients. Four test diets were prepared by mixing 60–75% of the reference diet with 40–25% of the test ingredient in order to reach similar levels of total P (0.67–0.73%) and to have a minimum of 35% protein (36.1–53.0%). Chromic oxide was added at 0.5% of the diet and used as an indigestible marker. A phytase solution was sprayed postpelleting on the test diets at a concentration of 1000 phytase units kg−1 (PU kg−1) dry diet. The test diets (with or without phytase supplementation) and the reference diet (nine treatments total) were fed to 3-year-old striped bass and were replicated in time ( n =3) during the 4-week period. Digestibility of DM was significantly lower ( P  < 0.001) for SBM and WM when compared with CGM and ISP and was not influenced by phytase supplementation. Crude protein digestibility was also not affected by phytase supplementation and was significantly lower ( P  < 0.09) for SBM when compared with ISP. Phosphorus digestibility was improved by approximately 23% with the addition of phytase for all four feedstuffs tested ( P  < 0.001). Furthermore, WM had significantly lower ( P  < 0.0001) P digestibility when compared with the other feedstuffs, irrespective of phytase supplementation.  相似文献   

7.
Five iso-nitrogenous (300 g kg−1 diet) purified diets with graded level of lipid at 40 (D-1), 60 (D-2), 80 (D-3), 100 (D-4) and 120 (D-5) g kg−1 diet were fed to Puntius gonionotus fingerlings for 90 days to determine their dietary lipid requirement. Two hundred and twenty-five fingerlings (average weight 2.34 ± 0.03 g) were equally distributed in five treatments in triplicate groups with 15 fish per replicate. Fifteen flow-through cement tanks of 100 L capacity with a flow rate of 0.5 L min−1 were used for rearing the fish. Specific growth rate (SGR), feed conversion ratio (FCR), nutrient digestibility, retention, digestive enzyme activity, RNA : DNA ratio and whole-body composition were considered as the response parameters with respect to dietary lipid levels. Maximum SGR and minimum FCR with highest RNA : DNA ratio, whole-body protein content and digestive enzyme activity was found in D-3 group fed with 80 g kg−1 diet lipid. Nutrient digestibility was similar in all the groups irrespective of the dietary lipid level. Maximum protein and energy retention was recorded at 80 g kg−1 dietary lipid fed group. However, from the second-order polynomial regression analysis, the maximum growth of P. gonionotus fingerlings was found at 96.9 g lipid kg−1 diet.  相似文献   

8.
Balance trials were conducted with African catfish Clarias gariepinus to assess the effect of phytase treatment of soybean meal-based diets on growth, feed utilization and nutrient budgets. Isocaloric (20–22 kJ g−1) and isonitrogenous (47–50% protein) diets were tested. In a first experiment the control diet (58% fish meal and 18% soybean meal) was compared with two diets containing 6% fish meal and 69% soybean meal, and two diets containing 29% fish meal and 41% soybean meal. One of each of these two diets had been pretreated with phytase (1000 units per kg dry diet). In the second experiment, the control diet (6% fish meal and 69% soybean meal, pretreated with 1000 units phytase kg−1 dry diet) was compared with four diets that were similar in composition but supplemented with increasing amounts of phytase (15, 380, 750, 1000 units kg−1 dry diet). Replacement of fish meal by soybean meal in the first experiment led to a depression in growth rate and feed utilization parameters. Results of both experiments clearly indicated a positive effect of phytase treatment, particularly on phosphorus digestibility and retention, and consequently the phosphorus conversion efficiency and the phosphorus budget. No differences in these parameters were found between addition of equal amounts of phytase by pretreatment or supplementation.  相似文献   

9.
Rohu, Labeo rohita (Ham.), fingerlings (average wt 3.38 g) maintained in 25 m2 cement tanks were fed fish-meal-based, 300 g kg−1 protein diets containing different levels (0, 0.25, 0.5, 0.75 and 1.0 g kg−1) of L -carnitine in triplicate over a period of 126 days. Fish that received 0.5 g kg−1 carnitine showed significantly higher growth than those fed the basal diet or the rest of the carnitine diets. Fat digestibility, food conversion efficiency and protein efficiency ratio were better in carnitine-fed fish; however, viscerosomatic and hepatosomatic indices decreased. Muscle proximate composition was affected as a result of carnitine treatment. The results of the present study demonstrate a positive effect of carnitine on the growth and body composition of rohu.  相似文献   

10.
The acceptability, digestibility and nutrient utilization of feeds containing cocoa husk were determined for tilapia Oreochromis niloticus fingerlings reared in a recirculation system. Three semipurified isonitrogenous diets formulated to contain 0, 100 and 200 g kg−1 of cocoa husk were fed to satiation three times daily. Although the feeds containing cocoa husk were acceptable to the fish, as indicated by their voracious consumption and positive weight gains, there were significant ( P  < 0.05) reductions in gross feed conversion efficiency with the cocoa husk feeds. Both apparent protein and dry matter digestibility were significantly ( P  < 0.05) reduced when 100 and 200 g kg−1 cocoa husk was fed. Specific growth rates of 3.51 and 3.34% per day, resulting from the two cocoa husk feeds, respectively, were significantly ( P  < 0.05) lower than growth rates of control fish. Apparent net protein utilization was not significantly affected ( P  > 0.05) by the 100 g kg−1 cocoa husk feed treatment. The consumption of the cocoa husk feeds could compensate for their low digestibility under acceptable fish yields and returns.  相似文献   

11.
Six isonitrogenous (320 g kg?1) and isolipidic (60 g kg?1) diets were formulated with graded levels (0, 5, 10 and 15 g kg?1) of dicalcium phosphate (DCP) and fungal phytase (750 and 1500 FTU kg?1 diet). Tra catfish (Pangasianodon hypophthalmus), 9.6 g, were fed the diets for 12 weeks. Each experimental diet was fed to eight replicates of fish to apparent satiation. At the end of the trial, fish fed the diets containing 15 g kg?1 DCP, 750 and 1500 FTU kg?1 phytase had higher growth performances, protein efficiency ratio and phosphorus retention than those fed the control diet, 5 g kg?1 DCP and 10 g kg?1 DCP diets (P < 0.05). Whole body ash and phosphorus concentration of fish fed the 10 g kg?1 DCP and 15 g kg?1 DCP diets were significantly higher than those of fish fed the control diet. Higher apparent digestibility coefficient of phosphorus was observed in fish fed the phytase supplemented diets. The present results indicate that supplementation of phytase at 750 FTU kg?1 and 1500 FTU kg?1 improves growth performances, feed and phosphorus utilization. The supplementation can completely replace dicalcium phosphate or other phosphorus sources in tra catfish feed and reduce the phosphorus discharge into environment.  相似文献   

12.
One of the three iso-nitrogenous (30% crude protein) and iso-energetic (15.0 MJ kg−1 diet) oil cake-based diets (groundnut, D-1; soybean, D-2 and mustard, D-3) was fed to the fingerlings (6.61 ± 0.06 g) of silver barb ( Puntius gonionotus ) for 120 days in triplicate fertilized ponds (0.04 ha) with a stocking density of 9000 fish ha−1. Fish were fed at 10% of their body weight for the first month, followed by 3% in the second and 2.5% in the third and fourth months of the culture period. The fish fed diets D-1, D-2 and D-3 grew from initial weights of 6.67, 6.67 and 6.50 g to 320.23, 298.23 and 305.13 g respectively. No significant variation ( P >0.05) was found in the growth and nutrient utilization of fish fed different dietary treatments. Net profits of Indian Rupees 67 385, 59 535 and 65 790 ha−1 were obtained in fish fed D-1, D-2 and D-3, respectively, within 120 days of culture. The results of this study suggest the possibility of the use of mustard oil cake as a dietary protein source for pond culture of silver barb in addition to groundnut and soybean oil cakes without compromising the growth, nutrient utilization, production performance and economics of culture of this fish.  相似文献   

13.
The present study was based on a 2 × 4 factorial design with two levels of dietary protein (33% or 37% CP) and four phytase levels (0.0, 750, 1,000, and 1,250 FTU/kg diet). African catfish, Clarias gariepinus (B.) (10.7 ± 0.4 g), were distributed into earthen ponds (100 m2 surface area per each) at a density of 4.5 fish per m2. Fish were fed on the experimental diets up to satiation twice a day for 3 months. Another experiment with the same treatments was conducted in 45-L tanks for 2 months to evaluate nutrient retention and digestibility. The growth and production of African catfish fed phytase-enriched diets were higher than those fed the control diet. The highest fish performance and production was observed with fish fed 37% CP enriched with a 1,200 FTU/kg diet of phytase. Feed intake was significantly affected by supplemental phytase alone, where it increased significantly as dietary phytase increased at both protein levels, resulting in similar FCR values (1.31–1.46). Additionally, the maximum values of protein efficiency ratio, protein retention, and phosphorus retention were obtained at 33% CP with phytase levels of 750–1,000 FTU/kg diet. It is also noticed that organic matter, protein, and phosphorus were more digestible in fish fed a 37% CP diet with high phytase levels. These results suggest that the optimum performance and production of African catfish were observed at a 37.0% CP diet enriched with a phytase level of 1,200 FTU/kg diet.  相似文献   

14.
A 2 × 2 × 2 factorial experiment was designed to study the main effect of dietary microbial phytase, citric acid, crude protein (CP) level and their interactions on growth performance, nutrient digestibility and body composition of Labeo rohita juveniles. Two basal diets were formulated using plant‐based ingredients containing either sub‐optimum (25%) or normal (35%) CP levels. Both the diets were supplemented with microbial phytase (U kg−1) and citric acid (%) at the level of 0, 0; 500, 0; 0, 3; and 500, 3 respectively. One hundred and twenty L. rohita juveniles (average weight 12.61–13.72 g) were randomly distributed in eight treatments, each with three replicates. Dietary microbial phytase alone had no significant effect on whole‐body ash content but addition of citric acid (3%) in the diet activated the phytase as evidenced by their significant interaction. A significant interaction between citric acid and microbial phytase was also found on weight gain%, specific growth rate, protein efficiency ratio. Increasing the dietary CP level from 25% to 35% significantly (P<0.01) decreased phosphorus and dry matter digestibility. Thus, these results showed that the growth‐promoting effect was higher in groups fed a sub‐optimum protein (25%) diet containing both 3% citric acid and 500 U kg−1 of microbial phytase than those fed 35% CP diets. This suggests that microbial phytase and citric acid in sub‐optimum CP diet had a synergistic effect on nutrient digestibility and growth performance of L. rohita juveniles.  相似文献   

15.
Triplicate groups of Mystus nemurus (Cuvier & Valenciennes) were fed isoenergetic semipurified diets containing seven dietary protein levels from 200 to 500 g kg–1 diet for 10 weeks. Dietary protein was supplied by graded amounts of a protein mixture (tuna muscle meal:casein:gelatine) at a fixed ratio of 50:37.5:12.5. Mystus nemurus fingerlings of initial weight 7.6 ± 0.2 g were fed close to apparent satiation at 2.5% of their body weight per day in two equal feedings. Growth performance and feed utilization efficiency increased linearly with dietary protein level from 202 to 410 g kg–1 diet and declined with protein levels of 471 g kg–1 diet or above. Protein efficiency ratio and apparent net protein utilization started to decline when the fish were fed with dietary protein levels exceeding 471 g kg–1 diet. Fish fed with lower protein diets (202–295 g kg–1 diet) had significantly ( P  < 0.05) higher carcass lipid content compared with fish fed with higher protein diets. Carcass lipid contents were inversely related to moisture content. Dietary protein did not significantly affect fish carcass protein and ash content. Using two-slope broken-line analysis, the dietary protein requirement for M. nemurus based on percentage weight gain was estimated to be 440 g kg–1 diet with a protein to energy ratio of 20 mg protein kJ–1 gross energy. This level of protein in the diet is recommended for maximum growth of M. nemurus fingerlings weighing between 7 and 18 g under the experimental conditions used in this study.  相似文献   

16.
The study was conducted to investigate the effect of dietary protein on nitrogenous excretion in the form of ammonia in Indian major carp, Labeo rohita (Ham.), fingerlings (3.0 ± 0.25 g). Fish were fed to satiation in a metabolism chamber. Approximately isoenergetic diets containing 230, 280, 330 and 380 g kg−1 protein were used at 28°C. Ammonia-N excretory energy ( U ) as a percentage of ingested food energy ( C ) increased with an increase in dietary protein level: from 4.3% in fish fed 230 g kg−1 to 6.0% in fish fed 380 g kg−1 dietary protein. The relationship between excretory energy and dietary protein level is modelled.  相似文献   

17.
Abstract.– Juvenile channel catfish Ictalurus punctatus (initial weight: 6.8 g/fish) were fed four practical diets containing 0, 250, 500, and 750 units of microbial phytase/kg and a diet containing 1% feed grade dicalcium phosphate (but no microbial phytase) under laboratory conditions for 12 wk. Fish fed the diets containing 250 units of microbial phytase/kg and above consumed more feed, gained more weight, and had a lower feed conversion ratio (FCR) in comparison to fish fed the basal diet containing no microbial phytase. Fish fed the diet containing dicalcium phosphate had intermediate weight gain and feed conversion ratio as compared to fish fed the basal diet and diets containing microbial phytase. Bone ash and phosphorus concentrations were lower for fish fed the basal diet than for fish fed other diets. No differences in weight gain, feed consumption, FCR, bone ash and bone phosphorus were observed among fish fed the diets containing various levels of microbial phytase. Fish fed the diet containing dicalcium phosphate had a lower bone phosphorus concentration than fish fed diets containing microbial phytase. Fecal phosphorus concentrations were lower for fish fed the diets containing microbial phytase than for fish fed the basal diet and the diet containing dicalcium phosphate. Results from the present study indicated that addition of 250 units of microbial phytase/kg to practical diets can effectively improve bioavailability of phytate phosphorus to channel catfish and may possibly eliminate the use of an inorganic phosphorus supplement in channel catfish diets. However, these data must be verified in trials conducted in ponds, prior to recommending removal of supplemental phosphorus from channel catfish diets.  相似文献   

18.
A feeding trial was conducted to study the effect of partial replacement of dietary monocalcium phosphate (MCP) with neutral phytase on growth performance and phosphorus digestibility in gibel carp, Carassius auratus gibelio (Bloch). Control diet was prepared with 2% MCP but without phytase (P0). Other three experimental diets were prepared by replacement of MCP by 25%, 50% and 75% respectively in comparison with control with supplementation of neutral phytase at 500 U kg?1 diet in each and designated as P25, P50 and P75 respectively. Gibel carp (initial body weight of 30.22 ± 1.98 g) were reared in twelve 300‐L cylindrical fibreglass tanks provided with filtered flow‐through tap water at 26–28°C. After 8‐week experiment, gibel carp fed with P50 had no obvious differences from the control group on weight gain (WG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency rate (PER) and survival rate. Phytase supplementation did not affect body compositions or muscle compositions. Crude protein and phosphorus (P) contents in the faeces of fish fed with the phytase‐supplemented diets were significantly lower than those of the control group. The apparent digestibility coefficients (ADCs) of crude protein and P in gibel carp were increased when fish fed with the diets in which MCP was replaced by neutral phytase. This study suggested that partial replacement of dietary MCP at 50% with neutral phytase was considered as a recommended dietary supplemental level and increased dietary P and protein availability.  相似文献   

19.
The quantitative dietary sulphur amino acid requirement of the Indian major carp, Labeo rohita (Hamilton), was determined by conducting a growth study. The experimental diets contained 400 g crude protein kg−1 from casein, gelatine and supplemental crystalline amino acids. Diets containing six graded levels of methionine (3.2, 6.5, 9.0, 11.5, 14 and 16.5 g kg−1) with a constant level of cystine (1.4 g kg−1) were formulated and fed to triplicate groups of Labeo rohita fingerlings twice a day to satiation for 60 days. The optimum dietary requirement for methionine was estimated using the break-point regression analysis at 11.5 g kg−1 of diet or 28.8 g kg−1 of dietary protein. Thus the total sulphur amino acid (Met + Cys) requirement was determined to be 12.9 g kg−1 of diet or 32.3 g kg−1 of protein. Higher survival, specific growth rate and food conversion efficiency values were observed for fish fed the diet containing optimum levels of sulphur amino acids.  相似文献   

20.
In a 8-week production-scale experiment at a commercial trout farm, the effects of dietary lipid level and phosphorus level on phosphorus (P) and nitrogen (N) utilization of rainbow trout (initial mean weight 99 g) were assessed. A low-phosphorus, high-lipid experimental diet (457 g protein, 315 g lipid, 9.1 g P  kg–1 dry diet) was compared with a commonly used commercial diet (484 g protein, 173 g lipid, 13.6 g P  kg–1 dry diet). P and N budgets were constructed using data from the production-scale experiment and digestibility data for the two diets. In addition, orthophosphate and ammonia-N waste were measured in effluent over one 24-h period. Relative to the commercial diet, the experimental diet resulted in significantly increased feed efficiency ratio, N retention and P retention, and substantially reduced dissolved, solid and total P waste (g kg–1 dry feed). Although N retention resulting from the experimental diet was higher, this was attributable to higher N (protein) digestibility of the experimental diet. Solid N waste (g kg–1 dry feed) resulting from the experimental diet was substantially lower, but dissolved N waste (g kg–1 dry feed) was not significantly different relative to the commercial diet. Mean effluent orthophosphate production (mg day–1 kg–1 fish) of fish fed the experimental diet was substantially lower than that of fish fed the commercial diet ( P  < 0.05), but effluent ammonia-N production (mg day–1 kg–1 fish) was not significantly affected by dietary treatment.  相似文献   

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