Apparent Net Protein Utilization Research Articles

Growth Performance and Nutrient Utilizations of Heterobranchus bidorsalis (Geoffory Saint Hilaire, 1809) Fed on Fermented Sorghum Bran Meal Diets

The growth of aquaculture faces a high cost of feed which is about 60% to 75% of total production costs. An effort should be made to increase the profit by reducing the cost of feed as minimal as possible. This study investigated the growth performance and nutrient utilizations of Heterobranchus bidorsalis fed on fermented sorghum bran meal diets. sorghum bran was fermented at 10% moisture for seven days and samples for proximate analysis were collected on the first, fourth and seventh day. The highest crude protein was obtained in seventh day fermentation with 17.59±1.53% and the lowest was obtained in the zero day (control) with 10.53±1.53. Four isoproteic diets (40% crude protein) were formulated at 25%, 50%, 75% and 100% inclusion level to replace maize meal. The diets were fed to H.bidorsalis for twelve weeks. The experimental fish were fed 5% body weight throughout the experiment. The results obtained from the feeding trial showed that the fish fed on 100% inclusion level shows significance difference (p<0.05) in mean weight gain compared to fish fed on other diets. The highest mean weight gain (MWG) was obtained in the fish fed on 100% inclusion level diet (D5) with 43.39±1.86g and the lowest was obtained in control diet (D1) with 28.97±0.54g. The highest Average Daily Growth (ADG) and Specific Growth Rate (SGR) were obtained in the fish fed on (D5) with 0.52±0.56 and 1.07±0.64 while the lowest were obtained in the fish fed on control diet with 0.35±0.51 and 0.91±0.65 respectively. The nutrient utilizations showed significant difference (p<0.05) in fish fed on (D5) compared to others. The highest feed conversion ratio (FCR) was obtained in fish fed on (D5) with 0.48±0.16 and the lowest was obtained in control with 0.41±0.24. The highest protein intake (PI), protein rating (PR) and protein growth rate (PGR) were obtained in the fish fed on (D5) with 43.12±1.27, 0.52±0.72 and 1.04±0.71 while the lowest were obtained in the fish fed on control with 29.99±0.71, 0.35±0.45 and 1.00±0.53 respectively. The highest Protein Efficiency Ratio (PER) was obtained in the fish fed on (D5) with 1.01±0.07 and the lowest was obtained in the fish fed 50% inclusion level diet (D3) with 0.95±0.62. The highest Apparent Net Protein Utilization (ANPU) and Apparent Net Lipid Utilization (ANLU) were recorded in the fish fed on (D5) with 23.35±0.92 and 161.22±0.26 while the lowest were recorded in the fish fed on (D1) with 14.68±1.05 and 131.27±0.74 respectively. This study revealed the positive effects of incorporating fermented Sorghum bran meal into the diet of H. bidorsalis.

Growth performance and physiological responses of striped catfish (Pangasianodon hypophthalmus) under different carbohydrates supplemented biofloc aquaculture systems

Biofloc technology is booming in inland aquaculture sector across the world especially in the places where water scarcity is high and land cost is expensive. Currently, the lack of appropriate selection and application feasibility of suitable carbohydrate in water quality management and fish health in biofloc aquaculture system are the major concern for wider adaptability of the technology. Therefore, the present experiment investigated the effect of different carbohydrate sources on overall wellbeing of striped catfish (Pangasianodon hypophthalmus) fingerlings. The experiment was randomly designed in four treatments (T1, T2, T3 and T4) and one control in triplicates in indoor tanks (1.0 m3). T1, T2, T3 and T4 groups supplemented with tapioca flour, sugarcane bagasse, molasses and jaggery, respectively under biofloc system at C:N ratio of 15:1, whereas the control group was not supplemented with carbohydrate source. Pre-acclimatized 525 fingerlings (7.2 ± 0.03 cm, 7.4 ± 0.003 g) were randomly stocked (35 nos. m−3) in the tanks and reared for 90 days. Overall, better water quality, fish performance and health status were observed in all the carbohydrates supplemented treatments than the control. Higher abundance of heterotrophic bacteria (5.88–118.18%) and biofloc associated microorganisms in jaggery supplemented biofloc, significantly (P ≤ 0.05) reduced total ammonia nitrogen, nitrite‑nitrogen, and increased nitrate‑nitrogen concentrations than other treatments. In the T4 treatment, jaggery supplementation enhanced biofloc volume, which influenced enhancement of fish body weight gain, specific growth rate, and improvement of feed conversion ratio than other biofloc treatments. Enhanced gut microbial population and digestive enzymes activity in fish significantly enhanced protein efficiency ratio, apparent net protein utilization, and flesh protein content in the T4 treatment. Fish showed significantly (P ≤ 0.05) higher haematological, immunological, and improved antioxidative responses in the T4 treatment than other treatments. Consumption of biofloc significantly (P ≤ 0.05) improved intestinal villi microarchitecture as higher villi surface area, width and height were detected in the T4 treatment. Collectively, the findings suggested that jaggery was the suitable carbohydrate source in terms of overall improvement of the culture system including growth performance and health status of P. hypophthalmus, if applied appropriately in biofloc aquaculture system. The present study comprehensively addressed carbohydrate sources, biofloc formation, total ammonia nitrogen management, fish growth and health resulting in better adoptability of biofloc technology by farmers in aquaculture.

Brewer’s yeast as a diet supplement in carp aquaculture: impact on production coefficients and haematological and biochemical plasma parameters

While brewer’s yeast (Saccharomyces cerevisiae), a rich source of proteins and B vitamins, is commonly used as an animal feed supplement, its use in aquaculture has been limited. Here, we assess its impact on 192 individuals of common carp (Cyprinus carpio) production and haematological and biochemical parameters from blood plasma using a control group fed commercial feed with 20% soybean meal and three test groups fed commercial feed with (i) 17.50% soybean + 2.50% brewer’s yeast (group B-2.5), (ii) 15% soybean + 5% yeast (group B-5) and (iii) 10% soybean and 10% yeast (group B-10). At the end of the experiment, all fish were weighed and measured and subsequently blood samples were taken from eight fish in each tank. There was a significant increase in total length (3%) and weight (5.37%) in group B-5. While fish muscle nitrogenous matter and protein efficiency ratio increased slowly across experimental groups, Fulton’s and Clark’s condition factors changed minimally (range 2.73–2.89%). Apparent net protein utilisation increased to 17.63% in B-10, suggesting that increasing yeast levels result in improved nitrogen utilisation. All fish muscle fat levels were within optimal range (4.16–4.68%) and, while there was a significant increase in erythrocytes in B-5 (up 0.40 T.L−1), haemoglobin levels increased only slightly in B-5 and B-10 (average 4.50 g.L−1) and B-10 had the lowest number of leukocytes (6.8 G.L−1). No significant changes were recorded in blood plasma biochemical parameters. Our results suggest that a 5% brewer’s yeast feed supplement represents a useful protein source for carp aquaculture.

Effects of Substituting the Two-Spotted Cricket (Gryllus bimaculatus) Meal for Fish Meal on Growth Performances and Digestibility of Striped Snakehead (Channa striata) Juveniles.

This study aimed to investigate the potential of using field two-spotted cricket Gryllus bimaculatus as the main protein source in fish feed for striped snakehead (Channa striata) juveniles. A 10-week feeding effect on growth performance, feed utilization, digestibility of major nutrients, including amino acids, and physiological outputs of nitrogen and phosphorus were determined. A total of 225 C. striata juvenile fish (Initial weight, 15.0 ± 0.1 g) were randomly distributed into three dietary groups in triplicate (25 fish per rectangular aquarium within a semi-recirculating system). Each group was hand-fed one of the experimental diets containing the graded level of a cricket meal (CM) replacing 0%, 50%, and 100% (CM0%, CM50%, and CM100%, respectively) of fish meal (FM) protein component. The results showed that growth performance and protein retention tended to increase with increasing dietary CM levels, whereas the waste outputs of nitrogen (N) and phosphorus (P) decreased. Apparent net protein utilization (ANPU) and P retention values increased with increasing levels of cricket meal inclusion level in the diet. There was a significant reduction in both N and P solid waste and dissolved waste output for snakehead with increased CM inclusion. There were significant effects of CM level on fish whole-body composition in terms of elevated protein and fat content. In conclusion, the CM is a viable alternative protein source for aquaculture feeds and can be included up to 100% as a replacement for FM without compromising the growth performance of striped snakehead Channa striata juveniles. This may also have a more favorable impact, with the potential to reduce N and P loading to the environment.

Growth performance and nutrient utilisation of Clarias gariepinus fed on sweet orange peels (Citrus sinensis) as carbohydrate source

The effect of substitution of maize meal with orange peel in the diet of Clarias gariepinus was investigated. Proximate composition, anti-nutritional content of differently processed orange peels and their effects on the growth of Clarias gariepinus were investigated. Soaked sweet orange peel meal was used in the formulation of the experimental diet and replaced maize at 25, 50, 75, and 100% inclusions respectively while the control diet was at 0% SOPMs replacement. The experiment consists of five treatments (1, 2, 3, 4 and 5) with two replicates in a completely randomized design (CRD). Two feeding trials lasted for a period of 8 weeks (56 days) and was carried out in a concrete experimental pond measuring 2 m x 1 m x 0.5 m. Two hundred Clarias gariepinus fingerlings, 10 g average weight were randomly distributed at 40 fish per replicate. Growth responses were checked and recorded weekly with a sensitive weighing balance (Mettler 5000) to the nearest grams after which feed quantity was adjusted. Fish were fed experimental diet twice daily (08:00 am and 05:00 pm) at 5% body weight, pond water was changed weekly during weight recording and the water quality parameters were monitored. The results of the proximate analysis of orange peel meals under different processing methods indicated that moisture content was highest in sundried peels (6.74) and lowest in cold-soaked peels (5.8%). Lipid content was highest in boiled peels (8.47) and lowest in fermented peels (7.71%). Protein content was highest in boiled peels (7.43) and lowest in sundried peels (6.40%). The highest NFE was recorded in the sundried peels (60.90) while lowest NFE value was recorded in the fermented (54.38). The anti-nutritional factors determined from the various processing method showed that boiling was more effective in reducing tannin (46.4% reduction), phytic acid (46.5% reduction), oxalate (54% reduction) and was least effective in reducing saponin (20% reduction). Fermentation was least effective in ANF reduction, tannin (21%) and phytic acid (15%); cold-soaking was more effective in saponin reduction (46.5%). Result obtained revealed that there was no adverse effects on the growth performance of the fish fed orange peel meals at 50% inclusion, thus sweet orange peel meals can replace maize up to 50% level of inclusion in the diet of Clarias gariepinus fingerlings without adverse effect with a corresponding SGR of (2.64±0.00). Apparent net protein utilization differed among the treatments (p<0.05).

Apparent nutrient utilization and metabolic growth rate of Nile tilapia, Oreochromis niloticus, cultured in recirculating aquaculture and biofloc systems

Abstract Introduction Recirculating aquaculture systems (RAS) and biofloc systems (BFS) have been considered eco-friendly aquaculture technologies in the last few decades. However, which system performs better has become a common question for fish farmers. Thus, this study aimed to compare the performances of the two aquaculture systems in culturing Nile tilapia, Oreochromis niloticus, larvae. Materials and methods The experiment was conducted by culturing 3-day post-hatching (dph) tilapia larvae in either the RAS or BFS for 43 days. At the end of the culture period, apparent net protein utilization (NPUa), apparent fat utilization (NFUa) and apparent net energy utilization (NEUa), metabolic growth rate (GRmet) of Nile tilapia, and water quality were compared using analysis of variance. Results The result showed, in general, that RAS performed better than BFS. NPUa and NEUa were significantly higher in Nile tilapia cultured in RAS than that of BFS, p < 0.05. While NFUa was not significantly different, p > 0.05. GRmet of tilapia cultured in BFS was higher in the first week but showed to be the same during the second week to the fourth week. At the end of the culture period (43 days), the GRmet of tilapia cultured in RAS was significantly higher than those of fish raised in the BFS. Other results showed that water quality parameters, including total ammonia nitrogen (TAN-N) and nitrite nitrogen (NO2–N), were lower in RAS than in BFS during the culture periods. While urea and CO2 were significantly higher in the rearing water of BFS than that of RAS, p < 0.05. Conclusion The RAS had better performance than the BFS in culturing tilapia larvae.

Sazan (Cyprinus carpio) Diyetlerinde Alternatif Protein Kaynağı Olarak Siyah Asker Sineği (Hermetia illucens) Larvası Ununun Kullanımı

A seventy-five-day feeding study was performed to investigate the usage of black soldier fly (Hermetia illucens) larvae meal as an alternative protein source in carp diets (Cyprinus carpio). In this study, experimental fish were fed with four different diets (fish meal-based without Black soldier fly larvae (BSFL) meal (BSFL0), 50% (BSFL50), 65% (BSFL65), and 75% (BSFL75) of fish meal substitution with BSFL), with triplicate. The carps (1.045±0.083 g) were randomly stocked into twelve flow-through tanks with a density of 50 fish per tank and reared for 75 days. Diet feed was provided to carps as a proportion of their biomass (5% of their mass per day) with two meals a day. Carps fed with BSFL65 meal showed positive effects on weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), apparent net protein utilization (ANPU), and feed conversion ratio (FCR). There were significant differences in moisture, crude protein, lipid, and ash content in the whole body among dietary groups (P<0.05). The protein content of the carp-fed BSFL75 diet group (20.22%) was significantly the highest among all three diet groups. Consequently, a BSFL meal can be considered as an alternative animal source of protein for the carp diet.

Protein-sparing effect of dietary lipid: Changes in growth, nutrient utilization, digestion and IGF-I and IGFBP-I expression of Genetically Improved Farmed Tilapia (GIFT), reared in Inland Ground Saline Water

Protein-sparing by lipid helps in conserving protein exclusively for growth with minimal inevitable protein breakage. It will subsequently reduce feed cost and nitrogenous pollutants in the habitat. In this context, an experiment of 60 days period was conducted to study the protein-sparing effect of lipid in the diet of Genetically Improved Farmed Tilapia (GIFT) (Oreochromis niloticus L) fingerlings reared in inland ground saline water (IGSW) at 10 g L−1 salinity. The experiment followed 4 × 2 factorial design with eight purified diets of four crude protein (CP) levels (30%, 35%, 40% and 45%), each with two lipid levels (6% and 10%). GIFT fingerlings of uniform size (3.00 ± 0.01 g) were acclimatized and distributed into eight treatment groups in triplicates corresponding to each of the prepared diets and fed to satiation three times daily. The results showed significantly (p < 0.05) higher percent weight gain (WG, 693.26%), apparent net protein utilization (ANPU, 34.03), protein efficiency ratio (PER, 2.35) and improved digestive enzymes (protease, amylase, lipase) activity with lower feed conversion ratio (FCR) for diets containing 35–45% CP and 10% lipid. According to two-way ANOVA, high dietary lipid (10%) resulted highest WG% (678.95), PER (2.02), ANPU (30.67) and lowest FCR (1.31) values. Increased whole body CP (15.54%) and lipid (7.61%) contents were observed in the fish fed high lipid (10%) diets. The viscerosomatic and hepatosomatic index also increased with increasing dietary lipid. The dietary CP levels have not significantly affected the body composition except total ash content. The highest insulin like growth factor-I (IGF-I) gene expression was observed in the liver of fish fed 35% CP with 10% lipid. Results revealed that increasing dietary lipid exhibited enhanced protein-sparing effect in GIFT fingerlings. Thus, the study concludes that a diet containing 35% CP and 10% lipid is optimal for GIFT fingerlings reared in IGSW of 10 g L−1 salinity.

Interactive effects of dietary protein and lipid on growth of Indian climbing perch, Anabas testudineus fry

Aim: To assess the optimum protein and lipid requirement of Anabas testudineus at its fry stage, based on the growth performance, feed efficiency and nutrient gain efficiency. Methodology: Eight experimental diets were prepared with four protein (35, 40, 45 and 50 %) and two lipid (9 and 13%) levels. The diets were designated as D1 (35 P/9L), D2 (35 P/13 L), D3 (40 P/9 L), D4 (40 P/13 L), D5 (45 P/9 L), D6 (45 P/13 L), D7 (50 P/9 L) and D8 (50 P/13 L). Each of the experimental diets was fed to triplicate groups of 10 fishes with an average individual body weight of 1.23 g in 24 glass aquaria. The diets were fed at about 4 % body weight per day in two equal rations for a period of 60 days. Results: Significantly (p&lt;0.05) higher weight gain (428 %), specific growth rate (2.77 % day-1), feed efficiency ratio (0.69) and protein efficiency ratio (2.34) and lower (p &gt; 0.05) food conversion ratio (1.45) was observed in fish fed with diet D5 (45% protein and 9% lipid). The nutrient retention parameters like protein retention, protein productive value, lipid productive value and apparent net protein utilization were also significantly (p &lt; 0.05) high in the treatment group D-5 fed with diet containing 45% protein and 9% lipid. Significantly (P&lt;0.05) higher whole body protein content was observed in the treatment group D5 (45% protein / 9% lipid) along with D4 and D6. Interpretation: The present findings on optimum protein and lipid requirement of 45% and 9%, respectively will help in formulating the cost-effective practical diets for Anabas testudineus fry, which is essentially required for quality seed production and grow out culture of this species in a commercial scale.

Bioconversion of Terminalia arjuna bark powder into a herbal feed for Labeo rohita: Can it be a sustainability paradigm for Green Fish production?

Surging demand of fish production for nutritional and livelihood security manifested with irrational use of synthetic growth enhancer and immunostimulants which are fostering the awful health concerned to human being and negatively affecting the beneficial micro-biota in aquatic ecosystem. The need of hour is to use environment friendly herbal therapy, as an alternate to those chemicals and compounds. The Terminalia arjuna is known for its excellent array of ethnomedicinal properties including antimicrobial, antioxidant and was reported to have positive effects on metabolomics of the animals. A 90-day experiment was conducted to ensure effective valorization of Terminalia arjuna bark powder (TABP) based feed in Labeo rohita. Four iso-nitrogenous {305.74 g crude protein (CP)/ kg diet} and iso-caloric {18.15 MJ gross energy (GE)/kg diet} experimental diets were formulated incorporating 0.0, 5.00, 10.00 and 15.0 g TABP /kg feed and designated as TABP0, TABP5, TABP10 and TABP15, respectively. 540 juveniles (average weight, 20.7 g, 45 fish per tank) were randomly stocked in 12 fibre reinforced plastic (FRP) tank (500 L water capacity). Fish were fed twice at 9.30 h and 5.00 h to satiation level. Results of this study revealed the highest growth rates {weight gain percentage (WGP) and specific growth rate (SGR)}, nutrient utilization {protein efficiency ratio (PER), apparent net protein utilization (ANPU), fat retention (FR) and energy retention (ER)} and survival percentage (SRP) in L. rohita at 10 g TABP/ kg feed. While feed conversion ratio (FCR) followed an inverse trend (P < 0.05) to growth rates. Growth rates, feed conversion, and nutrient utilization were similar in TABP0 and TABP15 group (P > 0.05). Viscerosomatic index (VSI) and craniosomatic index (CSI) were significantly affected (P < 0.05) while hepatosomatic index (HSI) was insignificant (P > 0.05). Whole body composition was influenced (P < 0.05) excluding ash content (P > 0.05). RNA content and RNA: DNA ratio were positively correlated to growth rates and nutrient retentions (P < 0.05). Thus, present study advocated that TABP at 12.3 g/kg could be utilized efficiently to produce healthy fish for human consumption thereby called Green Fish. Also, paved a prolific way to produce an effective TABP based medicated feed on large scale, having tried in field conditions individually and with commercial feed.

Protein digestibility and bioavailability in an F2 mouse cross between the selected fat mouse line and an M2 congenic line carrying the anti-obesity and anti-diabetic Tst allele.

The study was performed to investigate protein digestibility and utilization in an F2 cross (M2-F2 cross) between the selected Fat (F) line and an M2 congenic line. The congenic M2line carried the Fob3b2 quantitative trait locus (QTL) from the selected Lean (L) line previously shown to contain the Tst gene with leanness, anti-diabetic and resistance to diet-induced obesity effects. The main objective of the study was to test if some of the effects on leanness and obesity resistance of the L-line Fob3b2 could also be due to the effect of this QTL on nutrient digestibility and bioavailability. The F2littermates carrying either the Fat line segment within the Fob3b2 region or the L-line were compared when fed the high-fat diet. Eleven mice per genotype were individually housed in metabolic cages. In 5-day experimental period, body mass and diet intake were measured. The part of study was done on the F and L line and tested the difference in apparent protein digestibility on low-fat (LFD) and high-fat (HFD) diet. The nitrogen content was determined in the diet, faeces, and urine based on which, the apparent protein digestibility, apparent protein biological value and apparent net protein utilization were calculated There were no significant differences in any of these parameters on congenic line, confirming that the phenotypic effect on adiposity between the genotypes in the M2-F2 population was not due to the differential effect of the Fob3b2locus carrying the Tst gene on protein utilization. We conclude that the observed phenotypic effects of this gene region are due to direct metabolic actions rather than the effects on nutrient absorption and nitrogen utilization since there were no differences in apparent protein digestibility between L and F lines, irrespective to HFD or LFD. The age of animals had significant effect on the level of digestibility.

Evaluation of protein enriched co‐products originating from wheat fermentation in diets of common carp Cyprinus carpio to examine effects on growth response, mineral retention, haematological status and intestinal integrity

Six experimental isonitrogenous (380 g kg-1 crude protein) and isolipidic (80 g kg-1) diets were formulated for juvenile carp Cyprinus carpio. The fish meal protein component of a basal diet (control treatment) was effectively replaced by yeast protein concentrate unrefined (YPCU), yeast protein concentrate refined (YPCR), yeast protein concentrate potable alcohol (YPCPA) at 300 g kg-1 of total dietary protein originating from a novel wheat fermentation process. Distillers dried grains with solubles (DDGS) at two levels (150 and 300 g kg-1) of dietary protein were also tested separately. After an 8-week feeding trial, carp fed YPCU30 recorded the highest (p ≤ .05) growth performance and feed efficiency. The apparent net protein utilization of phosphorus, sodium, magnesium and chromium for all diets tested showed significant differences of retention efficiencies. The control fed carp had (p < .05) significantly lower phosphorus and magnesium efficiency than the carp fed other diets. Histological examinations showed the density of microvilli in the region of fish fed YPCU30, YPCPA30, DDGS15 and DDGS30 was decreased compared with the control fed fish with no significant differences were found among the treatments (p ≥ .05). Significant differences in the number of hepatocytes were observed between fish fed YPCR30 or YPCPA30 and DDGS30. Furthermore, no significant (p ≥ .05) differences were obtained in the number of hepatocytes in the fish fed YPCU30 and DDGS15 diets with fish fed the control diet. Hepatic structure showed that the liver of the fish fed the control, YPCU and YPCR diets appeared to be healthy with no signs of pathological change. In conclusion, fermented wheat-derived yeast protein concentrate and distillers dried grains with solubles are promising ingredients in carp diets to reduce feed costs and achieve aquaculture sustainability.

Evaluation of mealworms (Tenebrio molitor) meal as an alternative protein source for narrow‐clawed crayfish (Pontastacus leptodactylus) juveniles

An eighty-day feeding study was performed to investigate the effects of mealworm meal (Tenebrio molitor) on the growth, survival and moulting frequency of juvenile Narrow-clawed crayfish (Pontastacus leptodactylus). Three dietary treatment groups with triplicate were fed with a fish meal-based without MW (control diet: MW0), two diets with 50% (MW50) and 100% (Mw100) of fish meal substitution with MW respectively. P. leptodactylus juveniles (11.0 ± 0.05 mm, mean ±SE and 0.011 ± 0.002 g, mean ±SE) were randomly stocked into nine flow-through tanks with a density of 30 crayfish per tank and reared for 80 days. Crayfish fed with MW50 mealworm meal showed positive effects on weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER), apparent net protein utilization (ANPU), moulting frequency (MF) and feed conservation ratio (FCR), but lower survival rate (SR) as compared to the other diet groups. Protein and lipid contents of the whole body of the crayfish fed with replacement diet (MW50) were found to be higher than those of the other two diet groups (p<0.05). However, the MW100 diet slightly increased the moisture and ash contents of the crayfish. Our observation indicated that the addition of a 50% mealworm meal in the diet of P. leptodactylus juveniles improved the growth performance of the crayfish without causing any adverse effects. Therefore, T. molitor meal can be considered as an alternative animal source of protein for the narrow-clawed crayfish juveniles.

Protein to energy ratios and cost, performance, and ammonia excretion in juvenile jundiá (Rhamdia quelen), South American catfish

ABSTRACT: The determination of nutritional requirements, based on diets administered in practice, considers physiological specificities and sustainability are essential to the development of suitable aquaculture technologies for novel fish species. The growth of jundia (Rhamdia quelen Quoy and Gaimard) juveniles (31.54 ± 4.92 g) fed five diets comprising increasing levels of digestible protein (DP: 24, 29, 34, 39, and 44 %) and digestible energy (DE: 12.13, 13.39, 13.81, 14.64, and 15.06 MJ kg−1) with DP:DE ratios: 20, 22, 25, 27, and 29 g MJ−1, respectively, was evaluated. Each diet was fed to three groups of 25 fish for 75 days. Regression analysis showed that the different DP:DE ratios affected both growth and economic performance as well as excretion of total ammonia nitrogen. Fish fed diets with DP:DE ratios between 22 and 27 g MJ−1 achieved a higher daily weight gain, superior apparent net protein utilization, feed conversion rates, and lower feed costs. For the economically viable and environmentally friendly farming of jundia juveniles in the initial grow–out stage (30 to 80 g average weight), the best DP:DE ratio was 25 g MJ−1 DP:DE (34.05 % DP and 13.81 MJ kg−1 DE).

Growth performance of fingerlings of Clarias gariepinus fed fermented seed of Senna obtusifolia (Linn)

The effects of replacing soybean meal with graded levels of fermented Senna obtusifolia seed meals (SOSM) on the growth performance of Clarias gariepinus were investigated. Five isonitrogenous (42% crude protein) and isocaloric (25.7% NFE) diets were formulated in which fermented replaced soybean meal (SBM) at 0% (SOSM0), 25% (SOSM25), 50% (SOSM50), 75% (SOSM75) and 100% (SOSM100) inclusion levels and a commercial feed (CmF) as the second control. Three hundred and sixty (360) fingerlings of (Clarias gariepinus) mean weight (2.85±0.01g) were stocked at (20) fish per tank volume in triplicate groups per treatment and fed 3% body weight twice a day of the experimental diets for 180 days. The feeding rate was adjusted after weighing. The water qualities were within range recommended for Clarias gariepinus. There were no significant differences (p&gt; 0.05) in growth performance and nutrient utilization between the control groups and those fed the fermented SOSM diets at 25%. The commercial, 0% and 25% groups had the highest mean weight gain (279 to 280 g), significantly (P&lt;0.05) superior to the groups that received the, 50%, 75% while the group that received 100% SOSM diet had the poorest mean weight gain (132.72g). Feed conversion ratios (FCR) of all treatments ranged from (1.75 to 2.18). These values increased slightly by increasing levels of fermented SOSM from 50 to 100%. The best FCR, 1.75± 0.02, recorded for fish fed 25% fermented SOSM indicated a superior level of utilization of the SOSM diet by the fish. There was no significant difference (P&gt;0.05) in the protein intake among the group of fish fed 0 and 25%, but significant difference (P&lt;0.05) occur in fish fed 50, 75 and 100% fermented SOSM respectively. Protein efficiency ratio (PER) exhibited significant differences (P&lt;0.05) in all treatments except in the control diets that were not statistically different (P&gt;0.05) from the fish fed the 25% fermented SOSM. The PER values increased among the experimental fish with respect to the quantity of total feed intake. There were no significant differences (P&gt;0.05) in apparent net protein utilization (ANPU) among treatments CmF, 0% and 25%. The ANPU was highest in fish fed 0% fermented SOSM (91.6±0.04) while fish fed 75 and 100 % fermented SOSM in diets were 71.4±0.02 and 73.4±0.03 were the least. There was a significant (P&lt;0.05) difference in the effect of the inclusion levels of fermented (SOSM) on final body carcass composition among treatments. This study showed that soybean meal can be substituted with fermented Senna obtusifolia seed meal up to 25% level in Clarias gariepinus diets without any negative effects on the growth and feed efficiency.

Dietary guanosine‐monophosphate improves growth performance, feed utilization and intestinal morphology of whiteleg shrimp ( Litopenaeus vannamei ) maintained on soybean meal‐based diets

The present study evaluated the effects of dietary supplementation of individual or a combination of nucleotides in soya bean meal‐based diet on growth, survival, apparent digestibility and intestinal condition of whiteleg shrimp, Litopenaeus vannamei. The experimental protocol comprised a control set, and four test diets that were separately supplemented with 0.1% inosine monophosphate (IMP, D + I), 0.1% guanosine monophosphate (GMP, D + G), 0.1% mixture of IMP and GMP (D + IG) and 0.1% mixture of IMP, GMP, cytidine monophosphate (CMP) and uridine monophosphate (UMP) (D + IGCU). Triplicate groups of the shrimp (initial body weight = 0.99 ± 0.01 g) were fed four times daily for 8 weeks. Results demonstrated that D + G significantly enhanced body weight gain and specific growth rate in the shrimp compared with control and other dietary treatments with the various combinations of nucleotides (p 0.05). Shrimp fed D + G showed significantly higher feed intake and apparent net protein utilization compared with D + IGCU and, control and D + IG (p < 0.05) respectively. Nucleotide supplementation did not significantly improve the crude protein and lipid digestibility coefficients. This was evident when the data on these parameters were compared with those of the control. Shrimp fed D + G showed significantly improved intestinal villus height and body crude protein content (p < 0.05). In conclusion, GMP supplementation in soya bean meal‐based diet enhanced the growth, feed intake, protein utilization and villus height of L. vannamei.

Optimum dietary crude protein for culture of genetically improved farmed tilapia (GIFT), Oreochromis niloticus (Linnaeus, 1758) juveniles in low inland saline water: Effects on growth, metabolism and gene expression

A 60-day feeding trial was conducted to determine the effects of dietary crude protein (CP) on growth, metabolism and growth-related gene expression in genetically improved farmed tilapia (GIFT), Oreochromis niloticus juveniles reared in low inland saline water (ISW) of 5 g/l salinity. Three hundred and fifteen fish (initial weight 2.68 ± 0.01 g) were distributed (15 fish/tank in triplicates) in seven experimental groups (20–50% CP with 5% increment) following completely randomized design (CRD) and fed with seven isolipidic (6%), isoenergetic (16.74 MJ digestible energy/kg) and hetero-nitrogenous (20–50 % CP) purified diets, respectively. Results showed inverse relation between percent weight gain (WG%) and feed conversion ratio which were significantly (p < 0.05) varied in overall, linearly and quadratically due to varying dietary CP. Overall and linear trend of protein efficiency ratio and overall, linear and quadratic trend of apparent net protein utilisation were significantly (p < 0.05) decreased with increasing dietary CP. Overall, linear and quadratic trend of whole body CP along with overall and quadratic trend of whole body lipid contents were significantly (p < 0.05) increased and decreased, respectively with increasing dietary CP up to 35 % and then decreased further. Whereas, overall, linear and quadratic trend of whole body ash content was increased significantly (p < 0.05) with increasing dietary CP. Overall and quadratic trend of protease activity in 30–45 % CP fed groups was significantly higher (p < 0.05) than 20 and 50 % CP fed groups; but overall and linear trend of amylase activity in 20−25 % CP fed groups was significantly higher (p < 0.05) than 35–50 % fed groups. Overall, linear and quadratic trend of hepatic glutamate pyruvate transaminase activity in 40 % CP fed group was significantly lower (p < 0.05) than that of 20−25 and 45–50 % CP fed groups and similar to 30–35 % CP fed groups. However, these trends of hepatic lactate dehydrogenase activity of 40–45 % CP fed groups was significantly lower (p < 0.05) than 20–30 % fed groups and similar to 35 and 50 % CP fed groups. Whereas, overall, linear and quadratic trend of hepatic malate dehydrogenase in 35 % fed group was significantly lower (p < 0.05) than 20–30 % CP fed groups and similar to other groups. The hepatic insulin like growth factor-1 (IGF-1) and IGF-1 receptor expression showed high correlation (r=0.92 and 0.90, respectively) with WG%. The optimum dietary protein requirement of GIFT juveniles at 5 g/l salinity in ISW was found to be 34.53–38.10% based on both broken-line linear and second-order polynomial regression with respect to WG% and hepatic IGF-1 expression.

Dietary inclusion of non-conventional palm kernel meal enhances growth, digestive enzyme activities and carcass characteristics of juvenile rohu (Labeo rohita)

A 60-day feeding trial was performed to test the nutritional value and utilization possibility of palm kernel meal (PKM) as a feed ingredient for juvenile Labeo rohita. Five iso-nitrogenous diets were prepared with various inclusions of PKM which replaced sunflower oil cake and de-oiled rice bran namely, control (without PKM), T1 (50 g/kg PKM), T2 (100 g/kg PKM), T3 (150 g/kg PKM) and T4 (200 g/kg PKM). The experiment was conducted in 350 L fibre reinforced plastic tanks in triplicate and each tank stocked with twenty-five juvenile rohu (7.2 ± 0.01 g) were fed twice daily at 5% of body weight with the experimental diet. The growth performance values showed a higher overall linear trend in T2 and it is significantly different from control as well as T1 groups. Final results showed highest average body weight, specific growth rate, protein efficiency ratio, and apparent net protein utilization in a dose-dependent manner (p < 0.05). Significantly higher amylase, protease, and lipase activities were recorded in T2 treatment (p = 0.003, p = 0.001 and p = 0.002, respectively). Additionally, dietary PKM significantly lowered the aspartate amino transferase, alkaline amino transferase and alkaline phosphatase enzyme activities in a dose-dependent manner (p < 0.05). Significantly higher lactate dehydrogenase, malate dehydrogenase, superoxide dismutase and catalase activities in the liver tissues were recorded in T4 (p = 0.004, p = 0.01 and p = 0.02 and p = 0.001, respectively). Based on the polynomial regression analysis, the PKM inclusion at 26.17–100.11 g/kg can be effectively used in the diet of juvenile L. rohita as a non-conventional growth-promoting feed ingredient without any harmful effects on its growth performance and physiological activities.

Effects of replacing fish meal with cockroach (&lt;I&gt;Periplaneta americana&lt;/I&gt;) meal in the diet of African catfish (&lt;I&gt;Clarias gariepinus&lt;/I&gt;) fingerlings

This research investigated the growth performance of Clarias gariepinus fingerlings (mean weight 1.130.3g) fed cockroach meal (CM) as replacement for fish meal (FM). The fish were fed with three diets containing 45% crude protein; diet 1 (control 0% CM and 0% FM) diet 2 (10% FM, 0% CM), diet 3 (10% CM, 0% FM) for 56 days. The results showed significant differences (p&lt;0.05) for the growth parameters evaluated for the treatments. Cockroach meal-based diet gave the best results in terms of mean weight gain (1.39+0.39g), food conversion ratio (2.54+0.15), specific growth rate (1.440.29%/day), protein efficiency ratio (0.87±0.20), apparent net protein utilization (16.23±7.19) and survival rate of 62%. This was followed by fish meal-based diet while the control diet gave a significantly (p&lt;0.05) lower values. It can be concluded from the study that cockroach meal can substitute fish meal at 10% inclusion level. However, further study can be conducted for higher inclusion levels of cockroach meal in the diets of C. gariepinus.&#x0D; Keywords: Insect meal, protein, catfish, feed, growth.

Growth Performance of Heteroclarias Juveniles Fed Graded Levels of Autoclaved Castor Seed (Ricinus communis L.) Cake Based Diets

An 84 day feeding trial was conducted on the juveniles (42.51±0.09g) of hybrid catfish, Heteroclarias, in order to evaluate the nutritional potential of 30 minutes autoclaved castor seed cake isonitrogenous (40% crude protein) and isocaloric (3212Kcal/Kg) diets replacing soybean meal at 0, 12.5, 25, 37.5 and 50%, the diets being designated D1, D2, D3, D4 and D5 respectively. Prior to this, the castor seeds (Ricinus communis L.), ZiboCastor No. 3 variety, collected from Ado-Ekiti metropolis, Nigeria were subjected to 0, 20, 30 and 40 minutes autoclaved at 121oC, dehauled, grounded, oil extracted to form cake, then the proximate and antinutrients analysis were carried out. The preliminary tests on the seeds revealed 30 minutes level of autoclaved seeds was the best. The growth performance result showed that there were significant differences (p&lt;0.05) in the mean weight gain (MWG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER) and apparent net protein utilization (NPU) among the various diet levels with the progressive decline in the values of each parameter (except FCR that showed progressive increment) along the trend of increment of castor seed cake inclusion (D1, 0%; D2, 12.5%; D3, 25%; D4, 37.5% and D5, 50%). The survival rate followed the same trend of declination with the highest percentage recorded for D1 (93.33±6.67%), followed by D2 (83.33±3.33%), D3 (76.57±3.33%), D4 (66.67±3.33%) and D5 (60.00±5.77%) respectively. Hence the best growth performance and nutrient utilization was shown in D1 (control) followed by D2. It is therefore recommended that autoclaved castor seed cake at 121oC be included at not more than 12.5% inclusion level to reduce cost of feed without necessarily compromising fish growth rate.