Preliminary Characterization of European Sardine Transglutaminase

Abstract

The significant role of transglutaminase (TGase) in the setting of surimi led us to perform its preliminary characterization in sardine muscle. The time course of the reaction and the effect of enzyme level were studied. The temperature optimum was around 35°C and the thermal stability was studied in the 15-55°C range. Higher TGase activity was measured in sardine dark muscle than in the white muscle. A slow decrease of TGase activity during ice storage of sardine was recorded, but after eight days in ice it was about 50% of its initial activity. Cold storage of sardine for a short period did not affect TGase activity.     

Changes in the Chemical Characteristics of Gulbi,Salted and Dried Yellow Corvenia,During Drying at Different Temperatures

A few chemical characteristics of Gulbi, a traditional Korean seafood prepared from salted and dried Yellow corvenia (Pseudosciaena manchurica), were investigated during drying at different temperatures. When Gulbi was manufactured by sun-drying (the control), it had the highest thiobarbituric acid reactive substances (TBARS) and volatile basic nitrogen (VBN) values. They increased with increasing drying time at all temperatures in the hot-air drier. The TBARS value of Gulbi was lower when dried at 30 and 35°C than at 40°C and the control. The VBN of the control was higher than that of hot-air dried Gulbi at 30 and 35°C and lower than that of hot-air dried Gulbi at 40°C. The control had a VBN value of 20.8 ± 0.07% and the hot-air dried at 30°C, 18.0 ± 0.06; at 35°C, 18.6 ± 0.06; at 40°C, 23.8 ± 0.08 (p < 0.05), respectively. The salt content of the control and Gulbi dried at 30, 35, and 40°C were 22.9 ± 0.07%, 17.7 ± 0.06%, 18.0 ± 0.06%, and 24.3 ± 0.08%, respectively. The amino nitrogen content was much lower: 63.1 ± 0.80 mg/100 g and 65.5 ± 0.14 mg/100 g at 30 and 35°C than 78.3 ± 0.21 mg/100 g at 40°C. The results of this study also indicate that the Gulbi dried at 30 and 35°C had better chemical characteristics than those dried at 40°C when using hot-air drying and sun drying.     

Effects of Whitening Agents and Frozen Storage on the Quality of Sardine (Sardina pilchardus) Surimi: Physicochemical and Mechanical Properties

This work is focused on the effect of using whitening agents (WA) during a process followed by frozen storage (4 months at ?18°C) on the whiteness, quality parameters, and mechanical properties of sardine surimi. The whiteness of surimi exhibited a significant improvement when whitening agents (calcium carbonate and peroxide hydrogen) were used (48.75 to 60.24). Dynamic rheological measurement showed that storage moduli, G′, was considerably higher than loss moduli, G″, for both surimi with WA and control; however, the highest viscoelastic moduli were found in the treated surimi. In addition, the microstructure of surimi with WA showed more compact matrix and higher water holding capacity. On the other hand, most tested indexes showed quality losses throughout the frozen storage in both samples. Proteins underwent denaturation as indicated by the reduction in band intensities, especially myosin heavy chain (MHC) bands. Peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) measurements showed that lipid oxidation took place during storage; however, the degree of lipid oxidation was not relevant. Therefore, it was proved that the addition of whitening agents had a marked effect on the production of surimi with better functional attributes including whiteness, water holding capacity, and mechanical properties.     

Chemical and Nutritional Characteristics of Holothuria tubulosa (Gmelin, 1788); A Seasonally Comparative Study

Sea cucumbers belonging to the Holothuroidea class are a group of worm-like and soft-bodied echinoderms that live in nearly all marine environments. Mediterranean Holothuria tubulosa is an economic sea cucumber species found in Turkish seas. This study aimed to present the first report of detailed amino acid profile and investigate the biochemical and nutritional characteristics of H. tubulosa seasonally collected from one of the densest natural beds, located at Çanakkale Strait (Southern Coast of Marmara Sea), Turkey. According to our results, the highest protein, lipid, and ash contents (%) were found to be 10.2, 1.9, and 5.1, respectively. The highest percentages of saturated, monounsaturated, and polyunsaturated fatty acids were 42.9, 28.3, and 37.8, respectively. Total amino acids (mg/g crude protein) ranged between 867.2 and 974.0 among all seasons. All essential amino acids were found in body wall tissues and ranged between 7.1 and 5.9. Mineral composition was found to be desirable at the recommended and threshold levels. In general, the proximate composition of H. tubulosa was directly affected by seasons (p < .05); however, amino acid, fatty acid, and mineral compositions were found to be similar among all seasons, except summer (p > .05).     

鱼蛋白的综合利用途径2.酸贮液体鱼蛋白

酸贮液体鱼蛋白是开发低值鱼及水产加工废弃物中鱼蛋白的有效途径之一,本文就酸贮液体鱼蛋白的生产和使用状况进行了分析和讨论,并将鱼粉和酸贮液体鱼蛋白二者进行了比较。     

Apparent digestibility coefficients of selected feed ingredients for juvenile hybrid tilapia,Oreochromis niloticus×Oreochromis aureus

The apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, gross energy, phosphorus and amino acids in local fish meal (LFM), Peruvian fish meal (PFM), poultry by‐product meal (PMM), meat and bone meal (MBM), tilapia by‐product meal (TM), fermented soybean meal (FSBM), soybean meal (SBM), peanut meal, canola meal (CM), cottonseed meal (CSM) and de‐gossypoled cottonseed meal were determined for juvenile hybrid tilapia (7.18 ± 0.2 g, mean ± SD). A reference diet (RF) and test diets (consisting of 70% RF and 30% of the feedstuff) were used with 0.5% chromic oxide as an external digestibility marker. The juvenile hybrid tilapias were stocked in 500‐L fibreglass tanks at a density of 20 fish per tank. Faeces were collected from triplicate groups of fish using a faecal collection column attached to the fish‐rearing tank. The results indicated that the ADCs of dry matter for juvenile hybrid tilapia ranged 71.88–89.53% for animal products and 65.89–79.98% for plant products. For crude protein, apparent digestibility coefficients of protein (ADCp) exceeding 90% were observed for FSBM, SBM and PFM, and ADCp of MBM was the lowest among all the treatments. Apparent digestibility coefficients of lipid in all the treatments were above 90%; the results indicate that lipids from both animal and plant sources were well digested by hybrid tilapia. The ADCs of phosphorus of animal and plant feedstuffs ranged between 58.04–74.44% and 52.65–64.23% respectively. The lowest ADC of phosphorus was observed in CSM among plant ingredients and in MBM among animal ingredients. The ADCs of energy were similar to those of dry matter and protein; the highest and lowest ADCs of energy were found in PFM and CM respectively. In general, the amino acid availability coefficients tended to reflect the ADCp among highly digestible ingredients. For the animal products, the availabilities of amino acids in PFM, LFM and PMM were generally higher than that in TM and MBM; among all the plant products, the availabilities of amino acids in FSBM and SBM were higher than in CM. These results indicated that juvenile hybrid tilapia is able to utilize different feedstuffs efficiently.     

Amino acid availability and protein digestibility of several protein sources for Nile tilapia,Oreochromis niloticus

Apparent amino acid availability coefficients and protein digestibility of four animal products [fish meal (FM), meat and bone meal (MBM), poultry by‐product and feather meal] and four plant protein‐rich products [soybean meal (SBM), cottonseed meal‐28, cottonseed meal‐38 and corn gluten meal (CGM)] were determined for Nile tilapia, Oreochromis niloticus. Ingredients were incorporated to a practical reference diet at a 7 : 3 ratio (70% of reference diet and 30% of test ingredient). Chromic oxide was used as external digestibility marker. Among animal products poultry by‐product meal (PBM; 89.7%) and FM (88.6%) presented the highest apparent protein digestibility (APD) while MBM (78.4%) and feather meal (78.5%) presented the lowest APD. Among plant protein‐rich products CGM (91.4%) and SBM (92.4%) presented the highest APD values while cottonseed meal‐28 presented the lowest APD (78.6%). Average apparent amino acid availability of feed ingredients was similar to protein digestibility with 92.3%, 89.6%, 73.4%, 80.7%, 88.9%, 84.4%, 91.2% and 79.7% values for SBM, CGM, cottonseed meal‐28 and 38, FM, MBM, PBM and feather meal respectively. These results indicate that O. niloticus is able to utilize efficiently different feedstuffs.     

Effects of Pond Volume Manipulation on Production of Fingerling Largemouth Bass,Micropterus salmoides

Hatchery ponds were manipulated by timing of filling to increase the efficiency of production of fingerling largemouth bass, Micropterus salmoides. The effects on pond productivity of fertilizing with chicken manure versus plant meals (consisting of equal parts by weight of cottonseed meal, alfalfa meal, and wheat shorts) were also examined. When ponds were filled in stages, more favorable water temperatures for largemouth bass were achieved, and desirable dissolved oxygen concentrations were maintained. Chlorophyll a levels and plankton community respiration rates were higher in ponds that were fertilized with the plant meals than in ponds fertilized with chicken manure (25% dry matter). Secchi disk visibility was relatively greater in chicken manure ponds than in ponds fertilized with the plant meals; however all differences were not significant. Zooplankton densities were comparable among treatments. Filling ponds in stages had no significant effects on chlorophyll a, plankton community respiration rate, Secchi disk visibility, or zooplankton abundance and population dynamics. Daily production of largemouth bass was greater in ponds filled in stages and fertilized with plant meals than in other treatment ponds. Yield was highest in stage-filled ponds fertilized with plant meals and lowest in full ponds fertilized with chicken manure. Filling ponds in stages reduced the fertilizer cost per kilogram of largemouth bass by 50% in ponds fertilized with plant meals and by 65% in manure-fertilized ponds.     

Partial and complete replacement of fish meal by broad bean meal in feeds for Nile tilapia, Oreochromis niloticus, L., fry

A 16‐week feeding experiment was conducted to study the feasibility of using broad bean meal (BBM) as a replacement for fish meal (FM) for Nile tilapia Oreochromis niloticus fry, initial average weight 1.9±0.18 g. FM (50% of the diet) was used as sole sources of animal protein in the control diet 1. The replacement levels of BBM in diets (2–5) were 25%, 50%, 75% and 100% of the FM. Methionine (1%) and lysine (0.5%) were added to each diet except the control diet. Three groups of fish were fed each of five isonitrogenous (31.2% CP) and isocaloric (20.1 kJ g^?1), and performance was compared against a nutritionally balanced control diet at the end of the experiment. Nile tilapia fed the diet containing 50% BBM exhibited comparable growth with those fed the FM‐based control diet. Digestibility of protein, energy and lipid decreased with increasing levels of BBM above 50% of total replacement FM into the diet. Incorporation of BBM in the diets significantly affected the moisture, fat and energy of whole fish body. These results suggest that BBM can replace 50% of the FM in diet for Nile tilapia fry, without adverse effects on fish performance.     

Effects on digestibility and growth of juvenile cobia (Rachycentron canadum) fed fish or crab silage protein

The study was conducted in Cam Ranh, Vietnam, in 1000‐L tanks supplied with recirculated and biofiltered saltwater (33‰ and 28.4 °C) to evaluate the potential use of lizard fish (Saurida undosquamis) or blue crab (Portunus pelagicus) acid silage protein for juvenile cobia (23–25 g). Six isoenergetic test moist diets (4915–5125 kcal kg^?1), using either raw fish diet, fish silage diet (FSD), raw crab diet, crab silage diet (CSD), mixed raw fish/raw crab diet or mixed fish/crab silage diet (MSD), as part of the protein sources in the steam‐cooked diets, were fed to satiety to triplicate groups of 20 fish each for a 6‐week growth trial. Y₂O₃ was added as an inert indicator to determine the apparent digestibility coefficients (ADC) for macro nutrients and gross energy. Weight gain (185–286%) and specific daily growth rate (2.5–3.2% per day) were significantly higher in cobia fed the raw‐based diets and FSD than in fish fed CSD and MSD (34–90 and 0.7–1.5% per day). Feed conversion ratios (FCR) were significantly higher in the groups fed CSD and MSD diets (2.1–6.5) than the groups fed the other diets (1.0–1.2), resulting in significantly lower protein productive values (0.1–0.2) in the groups fed CSD and MSD than in the other groups (0.3–0.4). The FCR results were confirmed by significantly lower ADC values in fish fed CSD and MSD than those in fish fed the other diets. We thus conclude that the present raw‐based diets were better utilized by juvenile cobia than silage‐based diets, particularly the diet made from crab silage.     

Fatty Acid Profiles and Lipid Oxidation Status of Sun Dried,Deep Fried,and Smoked Sardine (Rastrineobola argentea) from Lake Victoria,Tanzania

Freshwater fishes contain long chain omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) of highest nutritional value. PUFAs in fish are susceptible to oxidative damage during processing and subsequent storage. Sardines (Rastrineobola argentea) are an important fish species of Lake Victoria, constituting 72.3% of the total landings by weight on the Tanzanian side of the lake. Fatty acid profiles and lipid oxidation status of sun-dried, deep-fried, and smoked sardines were investigated. Lipid oxidation was assessed by peroxide value, thiobarbituric acid reactive substances (TBARS), and free fatty acids. Fatty acids were analyzed by gas chromatography with flame ionization detector. The three omega-3 PUFAs: docosahexaenoic acid (C22:6n-3), docosapentaenoic acid (C22:5n-3), and eicosapentaenoic acid (C20: 5n-3) contributed 57–60, 63, and 38% of PUFAs in sun-dried, smoked, and deep-fried sardines, respectively. Lipid oxidation reactions were more pronounced in sardines dried on sand and rocks, with TBARS values 97.87 and 84.18 µmolMDA/kg, respectively. The polyene index was significantly lower (p < 0.05) in deep-fried sardines, indicating lower retention of PUFAs in the product. Lake Victoria sardines are a rich source of omega-3 PUFAs. PUFAs in sun-dried sardines are prone to oxidative damage. Smoking resulted in relatively higher retention of omega-3 fatty acids in products.     

Effects of dietary organic acids on growth, nutrient digestibility and gut microflora of red hybrid tilapia, Oreochromis sp., and subsequent survival during a challenge test with Streptococcus agalactiae

A 14-week feeding trial was conducted to determine the effects of dietary organic acids. The experimental diets were added with 0, 1, 2 or 3 g kg⁻¹ of a novel organic acid blend or with 2 g kg⁻¹ of potassium diformate and fed to triplicate groups of red hybrid tilapia ( Oreochromis sp.). Upon completion, tilapia were challenged by immersion with Streptococcus agalactiae . There was no significant difference ( P >0.05) in the growth, feed utilization and nutrient digestibility among treatment groups despite a trend towards improved results with fish fed organic acid-supplemented diets. Diet pH decreased, causing a reduction in the digesta pH of the stomach and gut. Total bacteria per gram of faeces were significantly ( P <0.05) reduced from 1.81 × 10⁸ colony-forming units (CFU) (control group) up to 0.67 × 10⁸ CFU in the fish fed organic acid diets. A similar trend was observed for adherent gut bacteria. Cumulative mortality of fish fed no organic acids was higher compared with fish fed organic acid-supplemented diets at 16 days post challenge. The data showed that dietary organic acids can exert strong anti-microbial effects and have the potential to exert beneficial effects on growth, nutrient utilization and disease resistance in tilapia.     

Replacement of fish meal with a mixture of different plant protein sources in juvenile Nile tilapia, Oreochromis niloticus (L.) diets

A plant protein mixture (PPM) was tested to replace fish meal (FM) in diets for juvenile Nile tilapia, Oreochromis niloticus. Fish averaging (±SD) 3.7±0.14 g were divided into 15 groups. Three groups were fed each of five isonitrogenous (33.6%) and isocaloric (4.7 kcal g^?1) diets replacing 0%, 25%, 50%, 75% and 100% of the FM protein with similar percentages of PPM (PPM0, PPM25, PPM50, PPM75 or PPM100 respectively). The PPM consisted of 25% soybean meal, 25% cottonseed meal, 25% sunflower meal and 25% linseed meal, and 0.5% of both methionine and lysine were added to each diet except for the control. After 16 weeks of feeding, the fish fed diets PPM75 and PPM100 exhibited growth performance not differing significantly from the fish fed control diet. PPM substitution of up to 75% of the FM protein did not result in differences in the apparent protein digestibility compared with the control, whereas in the PPM100 group digestibility was significantly lower than in the other groups, except for fish fed the PPM75 diet. The incorporation of PPM in diets did not significantly affect whole‐body dry matter, protein, fat or energy compared with the control. The cost–benefit analyses of the test diets indicated that the PPM diets were economically superior to FM. The protein from PPM can completely replace the FM protein in the diets for Nile tilapia, based on the results of this study.     

Apparent digestibility of selected feed ingredients in diets for juvenile hybrid tilapia,Oreochromis niloticus×Oreochromis aureus

The apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, ash, phosphorus, gross energy and amino acids of 10 selected ingredients for juvenile hybrid tilapia (7.05 ± 0.09 g) were determined using 0.5% Cr₂O₃ as an inert indicator. The feed ingredients tested in this study were corn gluten meal (CGM), corn byproduct, corn germ meal (CG), soybean meal (SBM), fermented soybean meal (FSM), soy protein concentrate (SPC), soy protein isolate, malt sprouts (MS), fish meal (FM) and earthworm meal (EM). The test diets were prepared by incorporation of 30% test ingredients into the reference diet. Reference and test diets were fed to the fish and the faecal samples were collected using a faecal collection column attached to the fish‐rearing tanks. The ADCs for dry matter, crude protein, crude lipid, ash, phosphorus and gross energy were 41.7–98.9%, 90.6–99.6%, 73.1–98.8%, 34.1–98.6%, 49.5–99.6% and 45.4–99.7% respectively. Soy protein isolate, FM and EM had higher dry matter, crude protein and gross energy ADCs. Corn byproduct and EM had higher crude lipid ADCs, and CG and EM had higher phosphorus ADCs. Corn germ meal had the highest ash ADC, while CGM had the highest value for gross energy. The lowest dry matter, crude protein, lipid and gross energy ADCs occurred in MS, while the lowest ash and phosphorus ADCs occurred in SPC. The amino acid ADCs ranged from 83.3% to 100%, exhibiting a positive correlation with crude protein digestibility for a given test ingredient. The feed ingredient digestibility of this study may provide useful information about nutrient and energy utilization to facilitate formulation of least‐cost practical diets for hybrid tilapia.     

Evaluation and Nutrient Quality of Detoxified Jackbean Seeds,Cooked in Distilled Water or Trona Solution,as a Substitute for Soybean Meal in Nile Tilapia,Oreochromis niloticus,Diets

ABSTRACT

Jackbean, Canavalia ensiformis, seeds were detoxified using eight different wet thermal detoxification methods in either distilled water (5% w/v) or trona (NaCO₂.NaHCO₃.2H₂O) solution. The effects of the detoxification methods on hemagglutinating, antitryptic and urease activities, and on the digestibility coefficient of crude protein and gross energy in the jackbean seeds were investigated. Cracked jackbean seeds cooked (100°C) in trona solution for one hour proved to be more effective as a method of inactivating the antinutritional factors in jackbean seeds. Dried detoxified jackbean seed meals were incorporated in dry practical diets providing 20% or 30% of total protein and fed to Nile tilapia, Oreochromis niloticus, fingerlings (mean weight, 6.7 g) twice daily to apparent satiation for 70 days. Mortality was low and no abnormal fish behavior was noted even when the detoxified jackbean meals provided 30% of total protein in diet. Growth and feed utilization indices, were similar (P > 0.05) between the diet in which cracked jackbean seeds cooked in water provided 20% of total protein and in diets in which cracked jackbean seeds cooked in trona solution provided 20% or 30% of total protein. Carcass composition and hepatosomatic index showed no definite trend among O. niloticus fingerlings fed the experimental diets.     

Feasibility Study of a Fish By-Product Recovery Plant with a Processing Capacity of 1,000 kg/Day

ABSTRACT

This study evaluates the feasibility of producing hamburger, silage, and leather using fish by-products in a medium-sized recovery plant with total capacity of processing up to 1,000 kg/day of whole fish. The average volume of fish by-products generated daily was 673 kg. The investment necessary to introduce these three technologies was US$47,193.13 in 1 year. The average cost to produce 1 kg of hamburger, silage, and leather was 1.24, 0.17, and US$1.77, respectively. The return of the investment was 56.16%, and the net present value US$570,582.16. The investment pay back was realized in 3.88 years, with a benefit/cost relationship of 1.31. For all the studied scenarios, sale price variations most influenced the economical parameters analyzed.     

Dried leaves of Rosmarinus officinalis as a treatment for streptococcosis in tilapia

Dietary application of dried Rosmarinus officinalis (rosemary) leaves as a treatment for streptococcal infection was studied in tilapia, Oreochromis sp. Feeding with dried rosemary leaves significantly reduced mortality following infection with Streptococcus iniae: 44% mortality in the group fed 8% rosemary, similar to oxytetracycline treatment (43% mortality), and significantly lower than the control (65%). Dietary administration of 16% rosemary significantly reduced mortality because of Streptococcus agalactiae infection in 44 g fish (62% and 76% in 16% rosemary and control, respectively), but not in a similar experiment conducted with 5.5 g fish. The antibacterial effect of rosemary on S. iniae was studied. Activity of rosemary cultivar Israel was reduced during the winter, but there was no significant change in cultivars Oranit and Star. Storage of powdered rosemary leaves at 50 °C resulted in fourfold and eightfold higher MIC_{24 h} values after 3 and 4.5 months, respectively. Storage at ?20 °C, 4 °C and 25 °C and autoclaving (120 °C) each resulted in a twofold increase in MIC_{24 h}. Repeated exposures of S. iniae to rosemary did not affect minimal inhibitory concentration, suggesting no development of resistance to rosemary.     

Effects of Oxygen Supplementation on Lake Trout Brood Stock

This study was conducted to determine the effects of oxygen supplementation and nitrogen supersaturation on the fecundity and performance of Lewis Lake strain lake trout, Salvelinus namaycush, brood stock. Performance of brood fish held in water supersaturated with oxygen was compared to that of controls raised at or below 100% saturation for 334 days. Incoming water averaged 78.4% saturation in the morning; the addition of oxygen increased saturation to 104.6%. As a result, average morning nitrogen saturation was reduced from 105.7% to 100.9%. In oxygen-supplemented water, peak daily oxygen saturation averged 129.0% in the afternoon. At this saturation level, average nitrogen gas was reduced to 98.4% saturation. Total gas pressure never exceeded 109.1% with oxygen supplementation; however, nitrogen supersaturation reached 110% in raceways with no oxygen supplementation. Weight gain, feed conversion, egg survival, egg size, and number of eggs per female were not affected by increasing oxygen saturation.     

Acceptability and digestibility by tilapia Oreochromis niloticus of feeds containing cocoa husk

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.     

Effects of cellulase addition to canola meal in tilapia (Oreochromis niloticus L.) diets

The effects of commercial cellulase enzyme products on the nutritive value of canola meal (CM) were determined in tilapia fry. Nine diets were prepared by adding cellulase enzyme (1–5 g kg^?1) to control diet (containing no canola), low canola (41.7 g kg^?1 CM) and high canola (208.3 g kg^?1 CM). Tilapia fry was fed for 90 days, and growth, feed conversion ratio (FCR), body composition and nutrient digestibility were determined. Fish fed the diets containing the lowest levels of canola meal (41.7 g kg^?1) had similar final weight and FCR relative to the group fed the control diet, and high canola diet showed significantly lower growth than other groups (P < 0.05), irrespective of cellulase enzyme. The addition of canola meal to tilapia diets resulted in lower protein digestibility and cellulose digestibility. There were no significant differences in body compositions in all treatments. Addition of enzymes to canola meal diets had no significant effects on growth performance, body compositions and nutrient digestibility. The results of this study indicate that use in higher level of canola meal in tilapia diet was adversely affected growth parameters and FCR. Adding dietary cellulase enzyme in different rations to diets showed no significant differences in growth parameter.