Effect of Dietary Protein Level20190819 95895 ozh97h

The present experiment was carried out to determine the Optimum dietary protein level (DPL) in supplementary diets for Nile tilapia, Oreochromis niloticus fry. Three diets containing 20, 25 and 30% CP were compared to a control group (natural food group) through studying their effects on growth performance, feed utilization and carcass composition. Four groups each of twenty five tilapia fry with an average initial weight of 0.31±0.10 g /fish were placed in twelve net enclosures. Fish were fed twice a day (9.00 a.m. and 14.00 p.m.) six days a week for 90 days. Feeding rates described as: for the 1st 30 days on 15% , for the 2nd 30 days on 10% and the last 30 days of the entire period on 5% of fresh body weight. The results showed significant differences at (P ≤ 0.05) in the final individual fish fresh body weights, average daily gain (ADG g/fish), specific growth rates (SGR %), feed conversion ratios (FCR), protein efficiency ratios (PER), and energy utilization (EU%) among the tested groups. Fish fed on the diet containing 25% DPL exhibited better growth performance in comparison to those fed on 30, 20% DPL or natural food group. The highest growth performance of O. niloticus was obtained at 25% DPL and the poorest was obtained at 30% DPL or natural food group. The lowest PER and PPV% of O. niloticus fry were obtained at 30% DPL. EU% increased by increasing DPL up to 25%, but there were no significant differences between 25% and 30% DPL. Increasing the DPL from 20 to 25% resulted in a significant increase at (P ≤ 0.05) in the dry matter (DM), crude protein (CP) and values of energy content (Eco) of the whole fish body, while ash content decreased. On the other hand, lipid content decreased significantly in all treatments at (P ≤0.05).Therefore, the current results confirmed that the diet containing 25% DPL is considered optimal for better performances of Nile tilapia fry under the present experimental conditions.

A 10-week feeding trial was conducted to assess the interaction between dietary protein level and fish weight on the growth, feed utilization, and physiological alterations of Nile tilapia, Oreochromis niloticus (L.). Fish were categorized into three weights; 0.4-0.5 g (fry), 17-22 g (fingerling), and 37-43 g (advanced juvenile). Diets containing 25, 35, or 45% crude protein (CP) were fed by triplicate to each fish weight. Fish growth, feed utilization, and protein turn-over were significantly affected by dietary protein level and fish weight, meanwhile their interaction significantly affected specific growth rate and protein efficiency ratio (PER) only. Unionized ammonia was significantly affected by dietary protein level, fish weight, and their interaction. Moreover, protein and lipid contents in whole-body of fish were significantly affected by dietary protein level and fish weight, while their interaction significantly affected total lipids content only. Ash content significantly differed with fish weight only. The optimum feed conversion ratio (FCR) was obtained with fry tilapia fed the 45%-CP diet; whereas, the poorest FCR was observed for advanced juveniles fed the 25%-CP diet. The lowest PER and protein productive value (PPV) values were obtained with the 45%-CP diet fed to advanced juveniles; whereas, the highest values were obtained with the 25%-CP diet fed to fry. The highest protein growth rate (PGR) was obtained with fry tilapia fed the 45%-CP diet, while the lowest one was obtained with advanced juvenile fed the 25%-CP diet. Hematological variables were significantly affected by protein level, fish weight, and their interaction except for serum lipids which was not significantly affected by the interaction. Activities of aspartate amninotransferase (AST) and alanine aminotransferase (ALT) in serum, liver, and muscles were significantly affected by dietary protein level and fish weight. The interaction significantly affected enzyme activities except for serum AST, which was not significant. The optimum growth of fry tilapia was obtained at 45% CP, while fingerling and advanced juvenile showed optimum growth performance with the 35%-CP diet. Excess protein in fingerling and advanced juvenile might be deaminated and used as energy source resulting in increased blood glucose, protein, and lipids as well as increased unionized ammonia in the environment.

2005

Experiment was conducted to study the effect of dietary protein level on growth and nutrient utilization by angel fish (Pterophyllum scalare) juveniles. Fifty-four juveniles (average wt. 2-2.5 g) were equally divided in three treatments with each of three replicates. Three formulated diets with graded protein levels, T1 (35% CP), T2 (40% CP) and T3 (45% CP) were fed to juveniles for 45 days. A trend of higher weight gain %, SGR, FER and PER was found with the increased CP level in the feed. Feed intake was similar in all the groups. T3 group fed with 45% CP registered highest weight gain % (43.26 ± 2.07), SGR (0.78 ± 0.04), FER (0.29 ± 0.01), which were significantly higher (P<0.05) than the T1 and T2 groups. Protein digestibility of T2 and T3 groups was significantly higher than the T1 group. Survival was similar in all the experimental groups. Diet with 45% CP with protein energy ratio of 112.62 mg protein/K cal. is ideal for juvenile angel fish for indoor rearing.

Archives of Agriculture and Environmental Science, 2023

The farming of Tilapia (Oreochromis niloticus) has conquered the significant popularity in tropical and subtropical regions, primarily due to its remarkable faster growth rate. The growth performance of the species makes it an attractive choice for many fish farmers. Additionally, Tilapia exhibits a com-mendable resilience to disease, further enhancing its appeal as a farming option. Furthermore, the low trophic feeding levels of Tilapia contribute to its desirability, making it an efficient and sustaina-ble choice for nutrition-conscious individuals. Due to the increasing prevalence of aquaculture pro-duction, there has been a significant surge in the demand for fishmeal. This particular protein source has relished the widespread popularity for many years and its demand has now more than doubled. The current growth rate of the aquaculture industry is outpacing the available fishmeal supplies, which are insufficient to meet the demand. According to scientific studies, it has been found that fishmeal can be effectively replaced with alternative sources without compromising the overall per-formance of the fish. This article presents a compelling case for the practicality of replacing fishmeal with alternative protein sources in the diet of Tilapia. These alternatives include terrestrial animal by-products, oilseed plants, single-cell proteins, and protein-rich plant derivatives. In order to mitigate the environmental impact of the fishmeal industry, it is crucial to implement measures that can ef-fectively address this concern. Moreover, it is crucial to highlight the significance of these sources from a nutritional perspective. The blood meal, meat and bone meal are highly beneficial options for incorporating essential amino acids and protein into the diet of Tilapia. These alternatives offer a rich source of nutrients that can effectively replace fishmeal. The minerals instead of amino acids could improve plant protein performance. Due to inconsistent findings, aquatic plants and single-cell proteins in Tilapia meals should be carefully considered. Fishmeal replacers need biological and eco-nomic analyses. Long-term evaluations should be done in practical culture systems rather than labs. In conclusion, it is imperative for Tilapia producers to contemplate the utilization of alternative dietary sources, as extensive research has demonstrated the scientific feasibility of substituting the fishmeal in the diet of Tilapia.

Journal of Applied …, 2011

his study was designed to determine the maximum replacing levels of fish meal (FM) by a plant protein mixture (PPM) in eight diets for Nile tilapia. The PPM consisted of cottonseed, sunflower, canola, seasme and linseed meals. FM in the basal diet was replaced by PPM in the diets at a replacing levels of 15, 30, 45, 60, 75, 90 and 100%. A total number of 480 Nile tilapia were randomly distributed into eight treatments, each in three replicates. After 12 weeks of feeding, results revealed that replacement of 15, 30 or 45% of FM by PPM did not significantly affect feed intake (FI), feed conversion ratio (FCR), protein efficiency ratio (PER), and the apparent digestibilities coefficient (ADC) of dry matter (DM), crude protein (CP) and ether extract (EE), while the higher replacing levels (60, 75, 90 or 100%) significantly (P<0.05) reduced these parametesr. Growth parameters were relatively parallel to those of FI, FCR and PER, whereas replacement up to 45% exhibited body weight (BW), body length (BL), weight gain (WG) and specific growth rate (SGR) not differing significantly (P<0.001) from the fish fed on control diet. Compared to control diet, increasing PPM in the diets significantly reduced hemoglobin, hematocrit and increased the activity of alanine aminotransferase (ALT) and aspartate aminotransferase (AST). The incorporation of PPM in diets did not significantly affect the whole-body dry matter (DM) and crude protein (CP). From economic point of view, replacement of FM by PPM up to 45% in tilapia diets reduced feed costs/kg diet and feed costs/kg weight gain by 11.40 and 6.74%, respectively.

PLOS ONE, 2023

The bullseye snakehead (Channa marulius) is considered as an affordable and robust freshwater fish for farming in Asia. However, there is limited knowledge on the species' full nutritional requirements to date with extensive gaps in our knowledge and particularly in precision aspects of protein requirements. Therefore, a three-month feeding trial was conducted under semi-intensive farming conditions to determine the protein requirement of bullseye snakehead using test diets containing 40 (P40), 45 (P45), 50 (P50), and 55% (P55) crude protein levels. The growth performance results revealed that the 55% dietary protein group (P55) had the highest final mean weight (14.09 g fish-1), and net weight gain (12.82 g fish-1). When compared to other dietary treatments, the final weight (R 2 = 0.921), and weight gain (R 2 = 0.913), displayed a linear increasing trend as dietary protein is raised. The lowest FCR was observed in 50% (1.94±0.01) and 55% (1.97±0.01) CP diet groups compared to dietary treatments. Further analysis has shown that the body protein content also significantly increased as dietary protein was raised to 55%. Although, a reverse trend was found in body lipid levels with increasing protein in the diet. The incremental dietary protein also elevated proximal intestinal protease activity but decreased amylase and lipase activity. The overall essential and non-essential amino acids levels of snakehead fillet muscle reflected an increase in dietary protein. Overall, this study has shown that the fish fed a diet with 55% crude protein attained the highest growth performance and nutrient profile of the whole fish when compared to other dietary treatments tested. It would appear we did not obtain the maximum potential for growth under the present experimental conditions due to the upper protein constraint of 55% in the diet. Further quantitative studies are suggested.

Egyptian Journal of Aquatic Biology and Fisheries, 2001

reochromis niloiicus fingeriings with initial body weight and length ranging from 20 to 39.5g and from 10 to 13.5cm., respectively .were reared in two cement ponds at a density of 4 fish/m". The two cement ponds were divided into five equal divisions (partitions) by nets. Fishes in each partition were fed on one of the experimental diets at 3% of body weight 6 times a week for a period of 130 days. This research was carried out at Al-Kanater AL-Khayria Fish Research Station to study the effect of dietary protein sources on growth of O. niloticus. Growth rate, average daily gain, specific growth rate and feed conversion ratio were determined. The results indicated that the highest growth rate (0.86), highest specific growth rate (0.96), maximum weight gain percentage (250.6%) and the lowest feed conversion ratio (2.37) were obtained for fish fed the formulated diet containing 25% protein, whereas the opposite was found for fish fed wheat bran alone. Results also showed that animal protein diet was better than plant protein diet for tilapia feeding. From the economical point of view,the results indicated that the balanced diet containing 20% protein was the most suitable diet for fish feeding in the cement ponds.

Aquaculture International, 2006

High levels of protein in fish feeds result in higher costs and nitrogen waste. Therefore, studies focused on protein substitution by alternative energy sources are necessary. Here we examine whether the protein:carbohydrate ratio in extruded diets affects protein-turnover parameters and the main tissue components in brown trout. Juvenile fish were adapted to two extruded diets: one higher in protein and lower in carbohydrate, C: 45/28 and the other higher in carbohydrate and lower in protein, HC: 37/40. Gross energy was 19 MJ kg )1 DM in both diets. Protein and lipid digestibility were high and similar in both groups (%90%), whereas total and carbohydrate digestibility and digestible energy were lower in the HC-fed group than in the C-fed group. Consequently, when fish were adapted to the diets, plasma levels of glucose and insulin differed between diets. HC-group presented higher plasma glucose levels and lower plasma insulin levels than C-group. Protein synthesis rates in white muscle, liver and whole body did not differ significantly between diets. In contrast, protein accretion rate of white muscle and whole body were significantly lower in the HC group, indicating an increase of protein degradation in these tissues and a decrease of synthesis retention efficiency. In spite of the daily protein intake of HC group was lower than C-group, the anabolic stimulation efficiency was increased by 34% in HC group. Protein and lipid contents in white muscle and liver were stable throughout the experiment. No hepatomegalia or increased fat deposition was observed in fish fed HC. Differences in specific growth rates (C: 0.88%; HC: 0.77%) were associated more with the lower protein consumption rate and the lower level of digestible energy in fish fed HC than with the higher dietary carbohydrate content of the diet.

Journal of Applied Biological Sciences, 2012

In this paper the effect of replacing fish meal with different protein sources was tested on growth performance, feed utilization and digestive enzyme activity in rainbow trout. Six experimental diets containing different protein sources were tested: 1) 100% fish meal (FM), 2) 60% fish meal + 40% plant protein (60FM/40PP), 3) 30% fish meal + 70% plant protein (30FM/70PP), 4) 100% plant protein (PP), 5) 50% poultry byproduct meal protein + 50% plant protein (50PP/50PM) and 6) 100% poultry by-product meal (PM). Rainbow trout with a mean initial weight of 15±2 g were fed experimental diets for 60 days. Results showed that 40% fish meal replacement with plant protein did not negatively affect the growth indices, feed utilization and muscle proximate composition. However, 70% and 100% replacement of fish meal with different protein sources resulted in significantly decreased growth, feed utilization and total fillet protein, but significantly increased total fillet lipid. The alkaline protease activity in 60FM/40PP, 50PM/50PP and PM groups were not significantly different with control, but significantly lower in 30FM/70PP and PP groups. The fish fed 100% plant protein (PP) resulted in decreased lipase activity compared to other feeding treatments, but no significant differences in lipase activity among other groups.

Egyptian Journal for Aquaculture

This study was conducted to investigate the effect three dietary protein energy ratio on growth performance, feed utilization and haematological indices of European sea bass Dicentrarchus labrax fingerlings culture in net enclosures (hapa, 30 m-3 each) for 60 days. The experimental treatments were assigned in triplicate. Three test diets were formulated to contain three different protein levels (450, 500, and 550 g kg-1 diet) and three lipid levels (174, 160 and 150 g kg-1 diet) to provided three different dietary protein: energy ratio (P: E ratio: 20 , 23 and 25 mg CP kJ-1 GE g-1 , P:E21, P:E23 and P:E25, respectively). A total of 180 European sea bass, Dicentrarchus labrax with an average initial body weight of 13.0 ± 0.5 g fish-1 were randomly distributed into nine net enclosures measuring (3 × 8 ×1.25m each) at a stocking density of 20 fish per net enclosure. Over the 60-days feeding period, growth, feed utilization efficiency and survival (%) of D. labrax fingerlings was improved significantly (P>0.05) with increasing dietary protein energy ratio up to P:E23 compared to P:E25 diets. The same trend was observed for the best feed conversion ratio (FCR). No statistical difference (P ≥ 0.05) was observed for the influence of dietary protein energy ratio on whole body proximate analysis of fish except for protein which recorded the highest values for fish fed P:E23 diet. Mean red blood cell counts (RBCs), mean white blood cell counts (WBCs), hematocrit (Hct), hemoglobin (Hb), total plasma protein, total plasma globulin, plasma

International Journal of Aquaculture, 2020

The captive breeding of the Silver catfish Schilbe intermedius was envisaged to promote the aquaculture and to reduce the overfishing of this endangered species. S. intermedius fingerlings were fed various dietary protein levels to investigate their growth performance, feed utilization and carcass proximate composition. Fish meal and casein were the sources of protein used in the study. Six isocaloric experimental diets containing 25%~60% crud protein (CP) diet have been fed to three-replicate six groups of forty (40) fishes (mean weight: (1.640±0.015) g) for 8 weeks. Both percent weight gain and feed efficiency ratio significantly increased with increasing dietary protein levels up to 45%, while there were no significant differences for protein levels from 45 to 60%. Growth performances and nutrient utilization parameters of fingerlings fed different diets varied significantly (p < 0.05) and the highest growth performance and nutrient utilization were obtained with fish fed on a 45% CP diet. The second order polynomial regression between dietary protein and specific growth rate (SGR) indicated that protein requirements of S. intermedius fingerlings ranged from 42.5 to 53% of diet. The highest protein content of the fish carcasses was found in fish fed 45% dietary protein and there was not significantly different (p > 0.05) with that of fish fed 60% dietary protein. Lipid content increased with increasing dietary protein levels. The dry matter and protein content of the initial sample were significantly higher (p > 0.05) than the values after feeding the fish with experimental diet.

Indian Journal of Animal Research, Volume 58 Issue 3: 401-405 (March), 2024

Background: Goldfishes are used as an ideal model for nutritional studies in larval and juvenile cyprinids. However, of the limited published data that is available on goldfish, protein requirements have varied from 29% to 53% for goldfish larvae. So the present study was undertaken to determine growth performance of goldfish, C. auratus fed with different dietary protein and lipid levels to develop nutritionally balanced diets. Method: In this study, Carassius auratus juveniles were fed with six diets containing two protein levels (300 and 400 g/kg) and three lipid levels (40, 80 and 120 g/kg) to evaluate the optimal dietary protein and lipid levels to determine growth performance, blood biochemical parameters, digestive enzyme activity and intestinal and liver histology. Result: According to the findings, gold fish juveniles when fed a casein-dextrin based semi-purified diet containing 400 g/kg dietary protein and 80 g/kg dietary lipid content, maximum development and feed utilisation are seen. Second-order polynomial regression also suggests that a diet with 400 g/kg protein and 80 g/kg lipid is best for juvenile goldfish growth and feed utilisation.

Egyptian Journal of Aquatic Biology and Fisheries

2011

Synodontis nigrita is an important indigenous species with aquaculture potential. However, this is yet to be achieved due to scanty information on its nutrient requirements. This study investigated the effects of different dietary crude protein levels on growth performance and haematological parameters of S. nigrita. Six hundred S. nigrita (mean weight 10.14 ± 0.04 g) were stocked at four treatments and three replicate in concrete tanks. Fish were fed on varying levels of experimental diets: 30%, 35%, 40% and 45% crude protein levels. Growth parameters such as weight gain (WG), specific growth rate (SGR), food conversion ratio (FCR) and protein efficiency ratio (PER) and haematological parameters of the fish samples: haemoglobin concentration (HB), packed cell volume (PCV), red blood cell count (RBC) and white blood cell count (WBC) were determined after the feeding trial. The data were analyzed using Statistical Package for Social Sciences (SPSS), Version 11, 2001 and Statistical Analysis Software (SAS), Version 8, 2001. Duncanʼs multiple rage test was used to compare the differences among means. The WG of fish fed on 40% and 45% protein levels (5.73 ± 0.06g and 6.37 ± 0.13 g) were significantly higher (p<0.05) than those of fed on 30% and 35% protein levels. The SGR of 40% (0.54) and 45% (0.59) protein levels were significantly higher (p<0.05) than fish fed on 30% and 35% protein levels. The FCR of fish fed on 45% protein level was lower (10.84) compared to other fish fed on 30%, 35% and 40% protein levels. The PER of fish fed with 30%, 35%, 40% and 45% protein levels were not significantly different. Haematological data of fish fed by 40% and 45% protein levels, Hb(7.06 ± 0.18 and 7.84 ± 0.59 g/dl) and RBC (2.68 ± 0.28 and 2.93 ± 0.04×10 6 /mm 3 ) were significantly higher (p<0.05) than in fish fed by 30% and 35% protein levels. S. nigrita requires high dietary protein levels for its successful aquaculture. Ajiboye and Faturoti (2011) Growth performance of Synodontis nigrita raised … Int. J. Aqu. Sci; 2(1): 27-35, 2011 28