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SGR
Selected AbstractsThe SGR 1806-20 magnetar signature on the Earth's magnetic fieldGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 2 2006M. Mandea SUMMARY SGRs denote ,soft ,-ray repeaters', a small class of slowly spinning neutron stars with strong magnetic fields. On 2004 December 27, a giant flare was detected from magnetar SGR 1806-20. The initial spike was followed by a hard-X-ray tail persisting for 380 s with a modulation period of 7.56 s. This event has received considerable attention, particularly in the astrophysics area. Its relevance to the geophysics community lies in the importance of investigating the effects of such an event on the near-Earth electromagnetic environment. However, the signature of a magnetar flare on the geomagnetic field has not previously been investigated. Here, by applying wavelet analysis to the high-resolution magnetic data provided by the CHAMP satellite, a modulated signal with a period of 7.5 s over the duration of the giant flare appears in the observed data. Moreover, this event was detected by the energetic ion counters onboard the DEMETER satellite. [source] Dietary arginine requirement of fingerling Indian major carp, Labeo rohita (Hamilton) based on growth, nutrient retention efficiencies, RNA/DNA ratio and body compositionJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2009S. F. Abidi Summary To quantify the optimum dietary arginine requirement of fingerling Indian major carp, Labeo rohita (4.10 ± 0.04 cm; 0.62 ± 0.02 g), an 8-week growth trial was conducted in eighteen 70-L indoor circular aqua-coloured troughs provided with a flow-through system at 28 ± 1°C. Isonitrogenous (40 g 100 g,1 crude protein) and isocaloric (4.28 kcal g,1 gross energy) amino acid test diets containing casein and gelatin as intact protein sources with graded levels of arginine (0.5, 0.75, 1.0, 1.25, 1.50 and 1.75 g 100 g,1 dry diet) were fed to triplicate groups of fish to apparent satiation at 07:00, 12:00 and 17:30 hours. Growth performance of fish fed the above diets was evaluated on the basis of absolute weight gain (AWG), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER), protein retention efficiency (PRE) and energy retention efficiency (ERE). Maximum AWG (2.61), SGR (2.80), best FCR (1.35), highest PER (1.85), PRE (37%) and ERE (76%) were recorded at 1.25 g 100 g,1 dietary arginine. Maximum body protein (18.88 g 100 g,1) and RNA/DNA ratio (5.20) were also obtained in a 1.25 g 100 g,1 arginine dry diet. Except for the reduced growth performance in fish fed arginine-deficient diets, no other deficiency signs were apparent. Based on the broken-line and second-degree polynomial regression analysis of the AWG, SGR, FCR, PER, PRE and ERE data, the optimum arginine requirement for fingerling Labeo rohita was found to be in the range of 1.22,1.39 g 100 g,1 of the dry diet, corresponding to 3.05,3.47 g 100 g,1 of dietary protein. [source] Effects of dietary l -carnitine supplements on growth and body composition in beluga sturgeon (Huso huso) juvenilesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 6 2008M. Mohseni Summary The effects of dietary l -carnitine on growth performance, whole body composition and feed utilization were studied in beluga, Huso huso. Fish were randomly allocated in 15 tanks (30 fish per tank) and triplicate groups were fed to satiety during 84 days one of five isonitrogenous (41% CP) and isoenergetic (20 MJ kg,1) diets, each differing in l -carnitine content [0 (control), 300, 600, 900 and 1200 mg kg,1 diet]. At the end of the trial, fish grew from 19- to 23-fold in weight, from 8.4 g to a maximum of 191 g. Fish fed 300,600 mg l -carnitine had the highest specific growth rate (SGR, 3.69 and 3.72% day,1) and protein efficiency ratio (PER, 0.95 and 0.99), and the lowest feed conversion ratio (FCR, 1.4 and 1.3) than the other groups (P < 0.0001). SGR, PER and FCR were the poorest for fish fed 1200 mg l -carnitine, while fish fed the unsupplemented and 900 mg l -carnitine supplemented diet showed intermediate performance. Body lipid concentration decreased significantly from 5.8 to 5.1% (P < 0.0001) with dietary l -carnitine supplementation increasing from 0 to 300 mg. Energy content was significantly lower in fish fed the 900 and 1200 mg l -carnitine diet (5.8 MJ kg,1), when compared with the other treatment groups (6.4,6.6 MJ kg,1). The results indicated that feeding sturgeon on diets supplemented with 300 mg l -carnitine kg,1 diet improved growth performance, and stimulated protein-sparing effects from lipids. [source] Influence of dietary amino acid profiles on growth performance and body composition of juvenile grouper Epinephelus coioidesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 2 2008Z. Luo Summary A feeding experiment was conducted to investigate the effects of dietary amino acid (AA) profiles on growth performance and body composition of juvenile grouper Epinephelus coioides (initial mean weight: 68.1 ± 1.0 g, mean ± SD). Five diets contained 30% fishmeal, 12% soy protein concentrate and 20% crystalline amino acids (CAAs); the control diet contained 54% fishmeal and 17% soy protein concentrate as intact protein sources. CAAs were added to the five diets to simulate the AA pattern found in white fishmeal protein (WFP), brown fishmeal protein (BFP), hen egg protein (HEP), grouper E. coioides juvenile protein (GJP) and red sea bream egg protein (REP), respectively. The highest WG and SGR were obtained in fish fed the control diet, followed by fish fed the diets with AA profiles of WFP and GJP. Fish fed the diets with AA profiles of BFP, REP and HEP showed relatively poor growth performance. Feed utilization showed a similar trend in growth parameters. Protein content of whole body among these treatments showed no significant differences (P > 0.05), but lipid content of whole body showed the highest value in the control group (P < 0.05). Dietary AA profiles significantly influenced plasma protein, cholesterol, triacylglycerol and glucose concentrations (P < 0.05). Dietary AA profiles significantly influenced the condition factor, hepatosomatic index and intraperitoneal fat ratio (P < 0.05). [source] Effect of inclusion of blue-green algae meal on growth and accumulation of microcystins in gibel carp (Carassius auratus gibelio)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2006M. Zhao Summary Six isonitrogenous (crude protein content: 38%) and isoenergetic (gross energy content: 17 kJ g,1) diets were formulated to investigate the effects of inclusion of blue-green algae meal on gibel carp (Carassius auratus gibelio). In each diet, 15% of the protein was supplied by fishmeal; the remainder was supplied by soybean meal and blue-green algae meal. Diet 1 was used as control with no blue-green algae meal whereas the content in diets 2,6 was 15.15, 29.79, 44.69, 59.58 and 74.48%, respectively. Each diet was fed to five groups of gibel carp for 12 weeks in a flow-through system. Final body weight and specific growth rate (SGR) of fish fed diet 5 were significantly lower than the control diet (P < 0.05). Mortality of gibel carp increased with increase in algae meal inclusion (P < 0.05), but there was no significant difference between fish fed diets 3,6 (P > 0.05). Feed conversion efficiency (FCE) decreased with the increase in algae meal inclusion (P < 0.05). Fish-fed diet 6 showed the highest feeding rate (P < 0.05), while there were no significant differences among the other groups (P > 0.05). Apparent digestibility coefficient of dry matter, protein, and energy decreased with increasing algae meal inclusion in the diets (P < 0.05). Aspartate aminotransferase (GOT) activity in the liver was not significantly different among groups (P > 0.05). Liver alanine aminotransferase (GPT) activity of fish-fed diets 4, 5 and 6 was significantly lower than the control diet (diet 1; P < 0.05). Microcystins in the muscle, liver, gallbladder, and spleen increased with increasing algae inclusion (P < 0.05). [source] Partial compensatory growth in hybrid tilapia Oreochromis mossambicus × O. niloticus following food deprivationJOURNAL OF APPLIED ICHTHYOLOGY, Issue 5 2005Y. Wang Summary The capacity of hybrid tilapia Oreochromis mossambicus × O. niloticus [23.2 ± 0.2 g (mean ± SE)] to show compensatory growth was assessed in an 8-week experiment. Fish were deprived of feed for 1, 2 and 4 weeks, and then fed to satiation for 4 weeks; fish fed to satiation during the experiment served as control. Water temperature gradually declined from 28.1 to 25.5°C throughout the experiment. Specific growth rate (SGR) decreased with progressive food deprivation. At the end of deprivation, body weight was lower in the deprived fish than in the control. Fish deprived for 4 weeks exhibited lower contents of lipids and energy in whole body, and higher moisture content and ratio of protein to energy (P/E) than those of the control; they also consumed feed faster than the control when normal feeding was resumed. All deprived fish showed higher food intake (FI) than that of the control during re-alimentation; however, enhanced SGR was only observed in the fish deprived for 4 weeks. There were no significant differences in digestibility of protein and energy, food efficiency (FE) or energy retention efficiency between the control and deprived fish. At the end of re-alimentation, deprived fish failed to catch up in body weight with the control, while content of moisture, lipids and energy, and P/E in whole body of the deprived fish did not significantly differ from that of the control. The results of the experiment revealed that the hybrid tilapia reared in freshwater showed partial capacity for compensatory growth following food deprivation of 4 weeks, and that growth compensation was due mainly to increased FI, rather than to improved FE. [source] Effects of the timing of initial feeding on growth and survival of spotted mandarin fish Siniperca scherzeri larvaeJOURNAL OF FISH BIOLOGY, Issue 6 2009L. Zhang The effects of delayed first feeding on growth and survival of spotted mandarin fish Siniperca scherzeri larvae were examined under controlled conditions. Morphometric characters [yolk-sac volume, oil globule volume, head depth (HD), body depth (BD), eye diameter (ED), musculature height (MH), mouth diameter (MD) and total length (LT)], body mass (M), specific growth rate (SGR) and survival were evaluated under different first-feeding time (2, 3, 4 and 5 days after hatching). Larvae began to feed exogenously at 2 days after hatching (DAH) and the point of no return (PNR) occurred between 5 and 6 DAH at 23° C, range ±1·0° C. The yolk volume of larvae first-fed at 2 days had a significant difference compared with that of larvae first-fed at 3, 4 and 5 days on 3 and 4 DAH. The larvae first-fed at 2 days achieved comparatively better growth performance than that of 3, 4 and 5 days. On 5 DAH, all morphometric characters had significant differences between 2 and 5 days and 2 and 4 days initial feeding, respectively. Total mortality was recorded on 9 DAH for the larvae first-fed at 5 days. On 12 DAH, significant differences were observed between 2 and 4 days and 3 and 4 days initial feeding for all morphometric characters. From 16 DAH to the end of experiment, all growth variables of the larvae first-fed at 2 days were significantly higher than those in other treatments. The SGR (2,9 DAH) first-fed at 2 and 3 days were significantly higher than 4 and 5 day treatments, and the SGR (9,16 DAH) first-fed at 2 days was significantly higher than 3 and 4 day treatments. There was no significant difference, however, of SGR (16,28 DAH) among treatments. Survival rate was significantly higher at 2 days initial feeding (27·42%) when compared with 3 (15·96%) and 4 days (7·92%) initial feeding at the end of experiment. The present study suggests that the first feeding of S. scherzeri larvae should be initiated at 2 days after hatching for achieving good growth and survival. [source] Effects of Dietary Recombinant Bovine Somatotropin Levels on Growth, Plasma Recombinant Bovine Somatotropin Concentrations, and Body Composition of Juvenile Korean Rockfish, Sebastes schlegeliJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2007Gwangyeol Yoo This experiment was conducted to study the effects of the graded recombinant bovine somatotropin (rBST) levels on growth, plasma rBST concentrations, and body composition of Korean rockfish, Sebastes schlegeli, and to estimate the optimum oral dosage of rBST. Seven experimental diets were formulated to be isonitrogenous and isocaloric and to contain 49.0% crude protein and 16.7 kJ available energy/g, with 0, 5, 10, 15, 20, 25, or 50 mg rBST/kg body weight (BW)/wk (rBST0, rBST5, rBST10, rBST15, rBST20, rBST25, and rBST50, respectively). After the feeding trial, fish fed all the diets supplemented with rBST showed higher weight gain (WG), feed efficiency (FE), specific growth rate (SGR), and protein efficiency ratio (PER) than those fed the rBST0 diet (P < 0.05). WG of fish fed rBST15, rBST20, rBST25, and rBST50 diets was significantly higher than that of fish fed rBST0 and rBST5 diets (P < 0.05); however, there were no significant differences among fish fed rBST10, rBST15, rBST20, rBST25, and rBST50 diets. FE of fish fed rBST15 and rBST20 diets was significantly higher than that of fish fed rBST0, rBST5, rBST10, and rBST50 diets, and fish fed rBST10, rBST25, and rBST50 diets had significantly higher FE than those fed rBST0 and rBST5 diets (P < 0.05). SGR of fish fed all the diets supplemented with rBST was significantly higher than that of fish fed rBST0 diet (P < 0.05); however, there were no significant differences among fish fed all the diets supplemented with rBST. PER of fish fed rBST15 and rBST20 diets was significantly higher than that of fish fed rBST0, rBST5, and rBST50 diets, and fish fed rBST10, rBST25, and rBST50 diets had significantly higher PER than those fed rBST0 and rBST5 diets (P < 0.05). Whole-body protein of fish fed rBST15 diet was significantly higher than that of fish fed rBST0, rBST5, and rBST10 diets (P < 0.05); however, there were no significant differences among fish fed rBST15, rBST20, rBST25, and rBST50 diets. Plasma rBST concentrations of fish fed all the diets began to rise at 3 h after oral administration of rBST; the maximum plasma rBST concentration peaked at 12 h and returned to the basal level at 24 h. Broken-line model analyses of WG and FE were 12.8 and 13.2 mg rBST/kg BW/wk, respectively. These results indicated that the optimum oral dosage could be greater than 12.8 mg rBST/kg BW/wk but less than 13.2 mg rBST/kg BW/wk in juvenile Korean rockfish. [source] Growth and Hematological Changes of Rockfish, Sebastes schlegeli (Hilgendorf) Exposed to Dietary Cu and CdJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2005Ju-Chan Kang Cd and Cu toxicological effect on growth and hematological parameters was investigated in juvenile rockfish Sebasres schlegeli after sub-chronic dietary Cd (0, 0.5, 5, 25, and 125 mg/kg) and Cu exposure (0, 50, 125, 250, and 500 mg/kg) for 60 d. In the experiment of dietary Cd exposure, weight and length SGR of the rockfish were significantly different from control, and a significant inverse relationship was observed between weight gain and the exposure concentration of dietary Cd at 25, 125 mg/kg (P > 0.05). Hematwrit and hemoglobin decreased significantly and were dose dependently in all Cd exposure. Glucose in serum was also increased significantly (P < 0.05). The concentration of total protein in serum was significantly lower than control at 5, 25, and 125 mgkg. No differences were observed in serum calcium concentration. Magnesium concentration in serum was increased signillcantly with dietary Cd concentration. In the experiment of dietary Cu exposure, Cu was inhibited weight gain and growth rate. No differences were observed in hematocrit, hemoglobin and RBCs compared to control. Contents of total protein, glucose, and Ca in serum remained stable. Mg concentration in serum was increased significantly at 500 mg/kg. [source] Reevaluation of the Dietary Protein Requirement of Japanese Flounder Paralichthys olivaceusJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 2 2003Kangwoong Kim An experiment was conducted to determine the dietary protein requirement by different analysis methods and to study the effects of dietary protein levels on growth performance and body composition in Japanese flounder Paralichthys olivaceus fed white fish meal and casein-based diets for 8 wk. After a 1-wk conditioning period, one of six isocaloric diets containing 30, 36, 42, 48, 54, and 60% crude protein (CP) was fed to fish at approximately 4,5% of wet body weight on a dry matter basis to triplicate groups of 15 fish averaging 13.3 ± 0.06 g (mean ± SD). After 8 wk of the feeding trial, weight gain (WG) and feed efficiency (FE) from fish fed 48% CP diet were similar to those from fish fed 42% and 54% CP diets, and were significantly higher than those from fish fed 30, 36 and 60% CP diets (P < 0.05). Fish fed 48 and 54% CP diets had a significant higher specific growth rate (SGR) than did fish fed 30 and 36% CP diets (P 0.05). Protein efficiency ratio (PER) was inversely related to the dietary protein level. No significant differences existed in hematocrit (PCV) and survival rate among the dietary treatments. Broken-line model analysis indicated that the optimum dietary protein level could be 44.0 ± 3.0% for maximum WG in Japanese flounder. Polynomial regression analysis of the dose-response showed that maximum WG occurred at 50.2% (R2= 0.94) based on WG, and the second-order polynomial regression analysis with 95% confidence limits revealed that the range of minimum protein requirement was between 38.9% and 40.3% based on WG. Therefore, these findings suggest that the optimum dietary protein requirement for maximum growth of Japanese flounder is greater than 40%, but less than 44% CP in the fish meal and casein-based diets containing 17.0 kJ/g of energy. [source] Soft gamma-ray repeater giant flares in the BATSE short gamma-ray burst catalogue: constraints from spectroscopyMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY: LETTERS (ELECTRONIC), Issue 1 2005Davide Lazzati ABSTRACT The giant flare observed on 2004 December 27 from SGR 1806,20 has revived the idea that a fraction of short (<2 s) gamma-ray bursts (GRBs) are due to giant flares from soft gamma-ray repeaters (SGRs) located in nearby galaxies. One of the distinguishing characteristics of these events is the thermal (blackbody) spectrum with temperatures ranging from ,50 to ,180 keV, with the highest temperature observed for the initial 0.2-s spike of the 2004 December 27 event. We have analysed the spectra of a complete sample of short GRBs with peak fluxes greater than 4 photon s,1 cm,2 detected by BATSE. Of the 115 short GRBs so selected, only 76 had sufficient signal-to-noise ratio to allow the spectral analysis. We find only three short GRBs with a spectrum well fitted by a blackbody, with 60 ,kT, 90 keV, albeit with a considerably longer duration (i.e. ,1 s) and a more complex light curve than the 2004 December 27 event. This implies a stringent limit on the rate of extragalactic SGR giant flares with spectral properties analogous to the December 27 flare. We conclude that up to 4 per cent of the short GRBs could be associated with giant flares (2, confidence). This implies that either the distance to SGR 1806,20 is smaller than 15 kpc or the rate of Galactic giant flares is lower than the estimated 0.033 yr,1. [source] Accumulation of chlorophyll catabolites photosensitizes the hypersensitive response elicited by Pseudomonas syringae in ArabidopsisNEW PHYTOLOGIST, Issue 1 2010Luis A. J. Mur Summary ,The staygreen (SGR) gene encodes a chloroplast-targeted protein which promotes chlorophyll degradation via disruption of light-harvesting complexes (LHCs). ,Over-expression of SGR in Arabidopsis (SGR-OX) in a Columbia-0 (Col-0) background caused spontaneous necrotic flecking. To relate this to the hypersensitive response (HR), Col-0, SGR-OX and RNAi SGR (SGRi) lines were challenged with Pseudomonas syringae pv tomato (Pst) encoding the avirulence gene avrRpm1. Increased and decreased SGR expression, respectively, accelerated and suppressed the kinetics of HR-cell death. In Col-0, SGR transcript increased at 6 h after inoculation (hai) when tissue electrolyte leakage indicated the initiation of cell death. ,Excitation of the chlorophyll catabolite pheophorbide (Pheide) leads to the formation of toxic singlet oxygen (1O2). Pheide was first detected at 6 hai with Pst avrRpm1 and was linked to 1O2 generation and correlated with reduced Pheide a oxygenase (PaO) protein concentrations. The maximum quantum efficiency of photosystem II (Fv/Fm), quantum yield of electron transfer at photosystem II (,PSII), and photochemical quenching (qP) decreased at 6 hai in Col-0 but not in SGRi. Disruption of photosynthetic electron flow will cause light-dependent H2O2 generation at 6 hai. ,We conclude that disruption of LHCs, possibly influenced by SGR, and absence of PaO produce phototoxic chlorophyll catabolites and oxidative stress leading to the HR. [source] Influence of dietary lipid/protein ratio on survival, growth, body indices and digestive lipase activity in Snakehead (Channa striatus, Bloch 1793) fry reared in re-circulating water systemAQUACULTURE NUTRITION, Issue 5 2010M. ALIYU-PAIKO Abstract Nine isoenergetic (18.5 kJ g,1) diets were formulated in a 3 × 3 factorial design to contain three protein levels (350, 400 and 450 g kg,1) for each of three lipid levels (65, 90 and 115 g kg,1), respectively, and fed twice daily for 8 weeks to fish of mean initial weight 3.34 ± 0.02 g reared in a re-circulatory water system. Temperature, pH and dissolved oxygen (DO) were maintained within the range 28,30 °C, 5.6,6.8 and 4.82,6.65 mg L,1 respectively throughout. Results show that fish survival was better in the groups fed 65 g kg,1 lipid while growth performance (% weight gain, WG; specific growth rate, SGR) and nutrient utilization (feed conversion ratio, FCR; protein efficiency ratio, PER; protein intake, PI) in the 65/450 and 90/450 g kg,1 treatments were similar and significantly (P < 0.05) higher than in fish fed the other lipid/protein ratio combinations. The body indices monitored (Hepatosomatic index, HSI and viscerosomatic index, VSI) were similar among the treatments whereas intestinal lipase activity was not significantly (P < 0.05) affected by increase in dietary lipid and protein levels. Carcass composition showed that dietary protein level affected body protein content positively in the 65 and 90 g kg,1 lipid treatments, but dietary lipid level did not affect body lipid content. A lipid/protein ratio of 65/450 g kg,1 is considered adequate for good growth performance and survival of Channa striatus fry. [source] Probiotic applications for rainbow trout (Oncorhynchus mykiss Walbaum) II.AQUACULTURE NUTRITION, Issue 5 2010Effects on growth performance, feed utilization, intestinal microbiota, related health criteria postantibiotic treatment Abstract The effect of dietary probiotics (Bacillus subtilis, Bacillus licheniformis and Enterococcus faecium) was assessed on rainbow trout (Oncorhynchus mykiss Walbaum) previously treated with oxolinic acid. After feeding on supplemented diets for 10 weeks growth performance, feed utilization, gastrointestinal colonization and health status were assessed. B. subtilis + B. licheniformis fed fish displayed a significant improvement of feed conversation ration (FCR), specific growth rate (SGR) and protein efficiency ratio (PER). High levels of probiotic species were observed in the posterior gastrointestinal tract as transient digesta associated populations and potentially resident mucosal populations. Levels of Bacillus spp. reached log 3.74 CFU g,1 on the mucosal epithelium and log 7.41 CFU g,1 in the digesta of fish fed diets supplemented with B. subtilis and B. licheniformis. Enterococci levels reached log 2.84 CFU g,1 on the mucosa and log 7.78 CFU g,1 in the digesta of fish fed E. faecium supplemented diets. Feeding trout the Bacillus probionts alone or synergistically with E. faecium resulted in elevated leucocyte levels. The results of the current study demonstrate a potential role of probiotics for stabilizing/reinforcing the gastrointestinal microbiota after antibiotic treatment. This could reinvigorate the intestinal defensive barrier mechanism and provide protection against secondary potential pathogens. [source] Dietary digestible lysine requirement and essential amino acid to lysine ratio for pacu Piaractus mesopotamicusAQUACULTURE NUTRITION, Issue 4 2010E.G. ABIMORAD Abstract To determine the digestible lysine requirement for pacu juveniles, a dose,response feeding trial was carried out. The fish (8.66 ± 1.13 g) were fed six diets containing the digestible lysine levels: 6.8, 9.1, 11.4, 13.2, 16.1 and 19.6 g kg,1 dry diet. The gradual increase of dietary digestible lysine levels from 6.8 to 13.2 g kg,1 did not influence the average values of the parameters evaluated (P > 0.05). The increase of dietary digestible lysine level to 16.1 g kg,1 significantly improved weight gain (WG), specific growth rate (SGR), protein productive value (PPV), protein efficiency rate (PER), and apparent feed conversion rate (FCR), but was not different from fish fed diets containing 19.6 g kg,1 lysine. Fish fed diets containing 16.1 and 19.6 g kg,1 digestible lysine showed lower body lipid contents than fish in the other treatments. The digestible lysine requirement as determined by the broken-line model, based on average WG values, was 16.4 g kg,1. The other essential amino acid requirements were estimated based on the ideal protein concept and the value determined for lysine. [source] Partial or total replacement of fish meal by local agricultural by-products in diets of juvenile African catfish (Clarias gariepinus): growth performance, feed efficiency and digestibilityAQUACULTURE NUTRITION, Issue 3 2010L. NYINA-WAMWIZA Abstract The study was undertaken to evaluate the growth performance and feed utilization of African catfish, Clarias gariepinus, fed six diets (D) in which fishmeal (FM) was gradually replaced by a mixture of local plant by-products. In diets 1 and 2, FM (250 g kg,1) was replaced by sunflower oil cake (SFOC). In diets 3 and 4, FM (250 and 150 g kg,1, respectively) was replaced by SFOC and bean meal (BM) while FM was totally substituted by a mixture of groundnut oil cake (GOC), BM and SFOC in diets 5 and 6. Sunflower oil cake was cooked, soaked or dehulled in order to determine the appropriate processing techniques for improving the SFOC nutritive value and to evaluate the apparent digestibility coefficient (ADC) values of the alternative diets. No significant differences were observed for daily feed intake, weight gain, specific growth rate (SGR) and feed efficiency (FE) among fish fed D1, D2, D3 (250 g kg,1 FM), D4 (150 g kg,1 FM) and D6 (0 g kg,1 FM). The highest SGR (3.2% per day) and FE (1.2) were achieved in fish fed D3, and the lowest in fish fed D5 (0% FM), suggesting a maximum acceptable dietary concentration of hulled SFOC below 250 g kg,1 in African catfish juveniles. Protein efficiency ratio ranged from 2.2 to 3.2 for all dietary treatments and was positively influenced by FM inclusion. African catfish were able to digest plant protein very efficiently in all diets tested. ADC of protein ranged from 88.6 to 89.5%, while ADC of energy was relatively low for diets containing hulled sunflower oilcake (71,74%) and high when sunflower oilcake was dehulled (78.6,81.3%). Similarly, ADC of dry matter was higher when sunflower was dehulled (72.1%) when compared with crude SFOC (60.5%). Soaking increased ADC values for neutral detergent fibre (NDF), dry matter, energy, protein and amino acids (AA). There were no significant differences in protein ADCs (88,90%) with increased levels of dietary vegetable ingredients. Both soaking and dehulling of sunflower before incorporation helped in the reduction of NDF, antitrypsin and tannins. Digestibility of all AA was generally high, greater than 90% for both indispensable and non-indispensable AA. Based on the data obtained, it was possible to totally replace menhaden fish meal with a mixture of vegetable proteins (72% of total dietary protein) when diets contained a relatively low percentage of animal protein (28% based on blood meal and chicken viscera meal) without negative effects. [source] Quantitative l -lysine requirement of juvenile black sea bream (Sparus macrocephalus)AQUACULTURE NUTRITION, Issue 2 2010F. ZHOU Abstract An 8-week feeding experiment was conducted to determine the quantitative l -lysine requirement of juvenile black sea bream Sparus macrocephalus (initial mean weight: 9.13 ± 0.09 g, SD) in eighteen 300-L indoors flow-through circular fibreglass tanks provided with sand-filtered aerated seawater. The experimental diets contained six levels of l -lysine ranging from 20.8 to 40.5 g kg,1 dry diet at about 4 g kg,1 increments. All the experiment diets were formulated to be isoenergetic and isonitrogenous. Each diet was assigned to triplicate groups of 20 fish in a completely randomized design. Weight gain and specific growth rate (SGR) increased with increasing levels of dietary lysine up to 32.5 g kg,1 (P < 0.05) and both showed a declining tendency thereafter. Feed efficiency ratio and protein efficiency ratio was poorer for fish fed the lower lysine level diets (P < 0.05) and showed no significant differences among other treatments (P > 0.05). All groups showed high survival (above 90%) and no significant differences were observed. The whole body crude protein and crude lipid contents were significantly affected (P < 0.05) by dietary lysine level, while moisture and ash showed no significant differences. The composition of muscle and liver also presented similar change tendency. Total essential amino acid and lysine contents in muscle both obtained the highest value when fish fed 32.5 g kg,1 lysine diet (P < 0.05). Serum protein, cholesterol and free lysine concentration were affected by different dietary treatments (P < 0.05), triacylglyceride and glucose contents were more variable and could not be related to dietary lysine levels. Dietary lysine level significantly affected condition factor and intraperitoneal fat ratio of juvenile black sea bream (P < 0.05) except for hepatosomatic index. There were no significant differences in white blood cell count and red blood cell count (P > 0.05), however, haemoglobin level was significantly influenced by different diets (P < 0.05). Analysis of dose (lysine level)-response (SGR) with second order polynomial regression suggested the dietary lysine requirement of juvenile black sea bream to be 33.2 g kg,1 dry diet or 86.4 g lysine kg,1 protein. [source] Effects of dietary protein to energy ratios on growth and body composition of juvenile Chinese sucker, Myxocyprinus asiaticusAQUACULTURE NUTRITION, Issue 2 2010Y.C. YUAN Abstract A growth experiment was conducted to investigate effect of dietary protein to energy ratios on growth and body composition of juvenile Myxocyprinus asiaticus (initial mean weight: 10.04 ± 0.53 g, mean ± SD). Nine practical diets were formulated to contain three protein levels (340, 390 and 440 g kg,1), each with three lipid levels (60, 100 and 140 g kg,1), in order to produce a range of P/E ratios (from 22.4 to 32.8 mg protein kJ,1). Each diet was randomly assigned to triplicate groups of 20 fish in 400-L indoors flow-through circular fibre glass tanks provided with sand-filtered aerated freshwater. The results showed that the growth was significantly affected by dietary P/E ratio (P < 0.05). Fish fed the diets with 440 g kg,1 protein (100 and 140 g kg,1 lipid, P/E ratio of 31.43 and 29.22 mg protein kJ,1) had the highest specific growth rates (SGR) (2.16 and 2.27% day,1, respectively). However, fish fed the diet with 390 g kg,1 protein and 140 g kg,1 lipid showed comparable growth (2.01% day,1), and had higher protein efficiency ratio (PER), protein productive value (PPV) and energy retention (ER) than other groups (P < 0.05). No significant differences in survival were found among dietary treatments. Carcass lipid content was positively correlated with dietary lipid level, but irrespective of protein level and inversely correlated with carcass moisture content. Carcass protein contents increased with increasing dietary lipid at each protein level. The white muscle and liver composition showed that lipid increased with increasing dietary lipid level (P < 0.05). Dietary protein concentrations had significant effect on condition factor (CF), hepatosomatic index (HSI) and viscerosomatic index (VSI) (P < 0.05). However, dietary lipid concentrations had no significant effect on CF, HSI (P > 0.05). Based on these observations, 440 g kg,1 protein with lipid from 100 to 140 g kg,1 (P/E ratio of 29.22 to 31.43 mg protein kJ,1) seemed to meet minimum requirement for optimal growth and feed utilization, and lipid could cause protein-sparing effect in diets for juvenile Chinese sucker. [source] Effect of dietary pantothenic acid supplement on growth, body composition and intestinal enzyme activities of juvenile Jian carp (Cyprinus carpio var. Jian)AQUACULTURE NUTRITION, Issue 5 2009Z.-P. WEN Abstract A 9-week feeding trial was carried out with juvenile Jian carp to study the effect of dietary pantothenic acid (PA) on growth, body composition and intestinal enzyme activities. Semi-purified diets with seven levels (4.0, 15.5, 25.6, 36.1, 45.9, 56.1 and 65.9 mg PA kg,1) of supplemental calcium d -pantothenate were fed to Jian carp (13.0 ± 0.0 g). PA improved specific growth rate (SGR), protein productive value (PPV), protein efficiency ratio (PER) and lipid production value (LPV) (P < 0.05). Fish fed the control diet had significantly lower feed efficiency (FE) than that in any other group (P < 0.05). Body protein content increased with increasing PA levels (P < 0.05), but moisture, lipid and ash of fish carcasses were negatively related to the graded PA levels (P < 0.05). Intestine protein content (IPC), hepatopancreas protein content (HPC) and activity of ,-amylase, lipase, trypsin, Na+,K+ -ATPase, alkaline phosphatase (AKP) and gamma-glutamyl transpeptidase (,-GT) were all positively affected by the dietary PA levels (P < 0.05), while intestine index (ISI) and hepatopancreas index (HSI) decreased with the increment of supplemental levels of PA (P < 0.05). These results suggested that PA could enhance fish growth and intestinal enzyme activities. The dietary PA requirement of juvenile Jian carp, Cyprinus carpio var. Jian (13.0,73.0 g), for optimal growth estimated by the broken-line analysis was 23.0 mg PA kg,1 diet. [source] Effect of dietary lysine and methionine supplementation on growth, nutrient utilization, carcass compositions and haemato-biochemical status in Indian Major Carp, Rohu (Labeo rohita H.) fed soy protein-based dietAQUACULTURE NUTRITION, Issue 4 2009P. SARDAR Abstract 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 D0 (without lysine or methionine supplementation), D1 (lysine supplementation alone), D2 (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. [source] Dietary pyridoxine requirement of juvenile Jian carp (Cyprinus carpio var. Jian)AQUACULTURE NUTRITION, Issue 4 2009W. HE Abstract In a 80-day feeding trial, a total of 1050 juvenile Jian carp (Cyprinus carpio var. Jian) with an average initial weight of 10.71 ± 0.05 g were fed semi-purified diets containing seven graded levels of pyridoxine (0.20, 1.71, 3.23, 4.96, 6.32, 8.58 and 12.39 mg pyridoxine kg,1 diet). Results indicated that with increasing dietary pyridoxine levels up to 4.96 mg kg,1 diet, percent weight gain (PWG) and specific growth rate (SGR) were improved, and no differences were found with further increase of pyridoxine levels. Feed intake also followed the similar pattern to that observed with PWG and SGR when dietary pyridoxine levels were ,6.32 mg kg,1 diet. But feed efficiency and protein efficiency ratio were not affected by pyridoxine levels. Crude protein of carcass, productive protein value and plasma ammonia concentration were improved with increasing dietary pyridoxine levels up to 4.96 mg kg,1 diet. Amylase activities in the intestine were improved with increasing dietary pyridoxine levels up to 4.96 mg kg,1 diet, but protease and lipase activities in the intestine were not affected by pyridoxine levels. Na+, K+ -ATPase and Gamma-glutamyl transpeptidase activities in proximal intestine, mid intestine (MI) and distal intestine (DI) were lowest when fed the diet containing 1.71 mg pyridoxine kg,1 diet. The alkaline phosphatase activities in MI and DI followed the same pattern. The dietary pyridoxine requirement of juvenile Jian carp based on PWG estimated by broken line model was 6.07 mg pyridoxine kg,1 diet. [source] Nutritional evaluation of waste date fruit as partial substitute for soybean meal in practical diets of juvenile Nile tilapia, Oreochromis niloticus L.AQUACULTURE NUTRITION, Issue 3 2009M.S. AZAZA Abstract The potential of waste date meal (WDM; low-quality date palm, Phoenix dactylifera L.) as a carbohydrate source in formulated diets for Nile tilapia was evaluated. Four isocaloric-practical diets (15.7 kJ g,1) were formulated incorporating WDM at 0, 100, 200 and 300 g kg,1 levels as partial substitutes for soybean meal (SBM). These were designated D0 [284 g crude protein (CP) and 383 g carbohydrate (CHO) kg,1 diet], D1 (279 g CP and 446 g CHO kg,1 diet), D2 (207 g CP and 495 g CHO kg,1 diet) and D3 (175 g CP and 578 g CHO kg,1 diet). Each diet was fed to three replicate groups of 30 fish [20.20 ± 0.09 g (±SE)] for 75 days. No feed-related mortality was observed during the entire experimental period. Final body weight (FBW) and specific growth rate (SGR) in the different treatments were statistically not significantly different (P > 0.05). Protein efficiency rate (PER) was lowest in diet D0 and increased with decrease of SBM content (D1,D3). A significant increase in whole body lipid content was recorded in fish fed diets D2 and D3. Results showed that WDM could be a substitute for SBM up to 300 g kg,1 in practical Nile tilapia diets without compromising growth. [source] Optimum dietary soybean meal level for maximizing growth and nutrient utilization of on-growing gilthead sea bream (Sparus aurata)AQUACULTURE NUTRITION, Issue 3 2009SILVIA MARTÍNEZ-LLORENS Abstract Six isonitrogenous [450 g kg,1 crude protein (CP)] and isoenergetic diets (23 kJ g,1) with six levels of defatted soybean meal inclusion (0, 132, 263, 395, 526 and 658 g kg,1) in substitution of fish meal were evaluated in gilthead sea bream of 242 g initial weight for 134 days. Fish fed diets S0, S13, S26 and S39 had a similar live weight (422, 422, 438 and 422 g, respectively) but fish fed diets S53 and S66 obtained the lowest final weight (385 and 333g, respectively), and similar results were presented in specific growth rate (SGR). Fish fed diets S53 and S66 also obtained the highest feed conversion ratio (FCR). Quadratic multiple regression equations were developed for SGR and FCR which were closely related to dietary soybean level. The optimum dietary soybean levels were 205 g kg,1 for maximum SGR and 10 g kg,1 for minimum FCR. Sensorial differences were appreciated by judges between fish fed S0 and S39 soybean level, but after a re-feeding period of 28 days with diet S0, these differences disappeared. [source] Nutrient values of dietary ascorbic acid (l -ascorbyl-2-polyphosphate) on growth, survival and stress tolerance of larval shrimp, Litopenaeus vannameiAQUACULTURE NUTRITION, Issue 2 2009J. NIU Abstract l -ascorbyl-2-polyphosphate (ApP) was used as a vitamin C source to investigate the ascorbic acid (AsA) requirements on growth performance and stress resistance of the larval white shrimp, Litopenaeus vannamei. Five isoenergetic and isonitrogenous fish meal-fish protein hydrolysate-based diets with five levels of ApP, AsA equivalent to 91.8, 188, 271, 360 and 436 mg kg,1 diet were fed to triplicate groups of L. vannamei (mean initial wet weight 1 mg) for 32 days. The diet with AsA 91.8 mg kg,1 showed high cumulative mortality after 10 days of feeding. After the 32-day trial, the shrimp that fed the diet had significantly lower survival and weight gain (WG, %) than those that fed 188, 271, 360 and 436 mg AsA kg,1 diets. Specific growth rate (SGR, % day,1) and final body wet weight (FBW, mg) showed the same pattern as WG (%). There were no significant differences in growth performance (FBW, WG and SGR) among the groups that fed 188, 271, 360 and 436 mg kg,1 of AsA at the termination of feeding trial. Broken-line regression analysis on WG indicated that 191 mg AsA kg,1 in the diet was the optimum for larval L. vannamei. On the contrary, dietary level of more than 360 mg AsA kg,1 was needed to ensure high resistance to stressful conditions such as low dissolved oxygen stressors. [source] Atlantic salmon (Salmo salar) postsmolts adapt lipid digestion according to elevated dietary wax esters from Calanus finmarchicusAQUACULTURE NUTRITION, Issue 1 2009A.S. BOGEVIK Abstract Wax esters (WE) in copepods constitute huge natural marine lipid resources, which can contribute as future lipid source in formulated diets in aquaculture, and thereby reduce the pressure on use of marine resources at higher trophic levels. The present study was undertaken to investigate factors affecting WE digestibility, including production of bile and lipases in Atlantic salmon fed diets containing high proportions of oil derived from copepods. Individually tagged postsmolt Atlantic salmon (initial weight 250 g) were distributed into three dietary groups in triplicate tanks and fed either a fish oil supplemented diet or diets where 50% or 100% of the fish oil was replaced with oil extracted from Calanus finmarchicus. WE accounted for 30.7% or 47.7% of the lipids in these latter diets, respectively. Over the 100 day feeding period, the salmon fed the fish oil diet displayed a significantly higher specific growth rate (SGR; 0.74) than fish fed the 100%Calanus oil diet (SGR; 0.67). The apparent digestibility coefficient of total lipid and total fatty acids was significantly higher in salmon fed the fish oil and the mixed diet compared to fish fed the pure Calanus oil diet. However, the fish appeared to enhance the lipid digestive capacity by increasing bile volume and the lipolytic activity. It is concluded that the digestion of WE in Atlantic salmon is poorer than for triacylglycerols. However, the digestive capacity is increased by elevating the bile content and lipase activity. At very high levels however, WE of lipid between 37.5% and 47.7%, are there no more compensation and WE utilisation decreases. [source] Effect of dietary phosphorus sources and varying levels of supplemental phosphorus on survival, growth and body composition of postlarval shrimp (Litopenaeus vannamei)AQUACULTURE NUTRITION, Issue 5 2008J. NIU Abstract Two experiments were conducted for 30 days each to investigate the effective phosphorus source and supplemental phosphorus levels for postlarval Litopenaeus vannamei. The first experiment was performed in postlarval shrimp (mean initial wet weight 2 mg) fed four isoenergic and isonitrogenous diets containing three supplemented inorganic phosphorus sources [D1: no supplemental phosphorus, D2: NaH2PO4·2H2O, D3: KH2PO4·2H2O, D4: Ca(H2PO4)2·2H2O]. The quantities of the three supplemental NaH2PO4·2H2O, KH2PO4·2H2O and Ca(H2PO4)2·2H2O were 11.6, 12.8 and 10 g kg,1 of the diet, respectively in order to make the three diets have the same total phosphorus. Growth performance (final mean body weight, FBW; weight gain, WG; specific growth ratio, SGR) of shrimp in D3 treatment was the highest and had significant difference with the D1 treatment. The survival of shrimp in D3 treatment was the highest and had significant difference with the other treatments. The mineral concentration and body composition of shrimp were not significantly different among treatments. We could conclude that KH2PO4·2H2O was the optimal phosphorus source for postlarval L. vannamei from the growth performance and survival. The second experiment was performed in postlarval shrimp (mean initial wet weight 0.88 mg) fed four isoenergic and isonitrogenous diets containing four supplemental KH2PO4·2H2O levels (d1, d2, d3 and d4 with 0, 5, 10 and 20 g kg,1, respectively). Shrimp in d2 treatment showed the highest growth performance and survival and also showed significant difference with other diet treatments. The whole body content of zinc (Zn) increased with the increase of dietary KH2PO4·2H2O and significant differences were observed when dietary KH2PO4·2H2O reached 5 g kg,1, excess KH2PO4·2H2O supplementation (10 and 20 g kg,1) had a negative effect on Zn content, the Zn content significantly decreased when KH2PO4·2H2O was 20 g kg,1. We can conclude that the amount of total phosphorus in the diet should be maintained between 20.9 and 22.0 g kg,1, the amount of supplemental KH2PO4·2H2O in the diet is less than 10 g kg,1. [source] A comparison among differently enriched rotifers (Brachionus plicatilis) and their effect on Atlantic cod (Gadus morhua) larvae early growth, survival and lipid compositionAQUACULTURE NUTRITION, Issue 1 2008A.S. GARCIA Abstract We evaluated the effect of differently enriched rotifers on the early growth, survival and lipid composition of Atlantic cod larvae (Gadus morhua). The enrichments tested were: (i) AlgaMac 2000®; (ii) AquaGrow® Advantage; and (iii) a combination of Pavlova sp. paste and AlgaMac 2000®. Larvae from treatment 3 [1.50 ± 0.11 mg dry weight (dw) and 7.10 ± 0.14 dw specific growth rate (SGR)] were heavier (P = 0.006) and grew faster (P = 0.004) than larvae from treatment 2 (1.03 ± 0.04 mg dw and 6.29 ± 0.04 dw SGR). No significant differences were found in the final weight and SGR among larvae from treatment 1 (1.21 ± 0.07 mg dw and 6.58 ± 0.20 dw SGR) and larvae from treatments 2 and 3. The treatment 3 also resulted in the best survival at the end of the experimental period, estimated to be 3 on a scale from 1 to 5, whereas the survival estimates for the two other groups were 1,2. Larvae from the treatment 3 reached 37 days posthatch with levels of ,6DPA 32-fold higher than newly hatched larvae. Differences in the larval enrichment of ,6DPA may explain the differences in growth and survival of the Atlantic cod larvae. [source] Dietary vitamin A requirements of juvenile Japanese flounder Paralichthys olivaceusAQUACULTURE NUTRITION, Issue 1 2005L.H.H. HERNANDEZ Abstract A 70-day feeding experiment was conducted to assess the dietary vitamin A (VA) requirements of juvenile Japanese flounder (Paralichthys olivaceus). Six semi-purified diets with VA supplementations of 0, 5000, 10 000, 15 000, 20 000 and 25 000 IU kg,1 were fed twice a day to triplicate groups of 20 juveniles per tank with an initial weight of 1.59 ± 0.01 g (mean ± SE). Weight gain (WG) and specific growth rate (SGR) increased as dietary VA increased up to 10 000 IU kg,1. Significantly lower WG and SGR were observed for the 0 IU kg,1 treatment than for treatments of 5000, 10 000 and 15 000 IU kg,1. Highest WG and SGR were observed in fish fed 10 000 IU kg,1; slightly lower values were recorded in fish fed 15 000, 20 000 or 25 000 IU kg1. No significant difference was observed in survival rate among treatments. Whole body total lipid was significantly higher in fish fed 0 and 5000 IU kg,1 than for other levels. Reduced growth and small livers were observed as signs of VA deficiency in fish fed 0 IU kg,1. Slightly reduced growth and pale fragile livers were observed as effects of VA excess in fish fed 25 000 IU kg,1. Total retinol contents in liver and eyes increased with increasing levels of dietary VA. No retinol was detected in livers, and significantly lower total retinol content was observed in eyes, of fish fed 0 IU kg,1. WG analysed by the broken line method indicated that an optimum dietary VA requirement of 9000 IU kg,1. [source] Digestibility and growth performance of juvenile rainbow trout (Oncorhynchus mykiss) fed with pea and canola productsAQUACULTURE NUTRITION, Issue 2 2003D.L. Thiessen A digestibility experiment and subsequent 84-day feeding experiment evaluated the use of pea and canola meal products in diets for rainbow trout. The effect of milling and heat treatment on nutrient, dry matter and energy digestibility of raw/whole peas, raw/dehulled peas, extruded/dehulled peas and autoclaved air-classified pea protein was determined. Digestibility of the protein component was uniformly high for all pea ingredients (90.9,94.6%), regardless of the processing treatment. Autoclaving or extrusion increased starch digestibility by 41,75% (P , 0.05), which consequently increased energy and dry matter digestibility of whole and dehulled peas. Autoclaved air-classified pea protein had superior protein (94.6%), energy (87.0%) and dry matter (84.0%) digestibility (P , 0.05). It was demonstrated that inclusion of 25% dehulled peas, 20% air-classified pea protein or 20% canola meal fines was feasible in trout diets allowing for replacement of soya bean meal. The data showed no difference (P , 0.05) in feed intake, final weight and specific growth rate (SGR) measurements, and feed utilization was not compromised with inclusion of pea or canola meal products as the primary plant ingredient. It was concluded that dehulled peas, air-classified pea protein and canola meal fines are suitable ingredients for use in trout diet formulation at a level of 20%. [source] Evaluation of carbohydrate rich diets through common carp culture in manured tanksAQUACULTURE NUTRITION, Issue 3 2002P. KESHAVANATH 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. [source] | ||||||||||||||||