Effect of different feeds on the growth,survival and reproductive performance of zebrafish,Danio rerio (Hamilton, 1822)

Present experiment was conducted to determine the effect of different feeds with varying protein levels on the growth, survival and reproductive performance of zebrafish, Danio rerio. The control diet (T1) was wild‐collected zooplankton from local fish ponds, while test diets with 350 g kg^?1 protein (T2), 400 g kg^?1 protein (T3) and 450 g kg^?1 protein (T4) were formulated and fed to fish for a period of 210 days. The significantly (P < 0.05) highest mean weight gain and specific growth rate were observed in T1, which were similar with T3 and T4. The significantly (P < 0.05) highest number of egg production per female and relative fecundity were found in T1, followed by T4 and T3 while T2 produced lowest number of eggs. No significant (P > 0.05) differences were observed in brood survival rate, fertilization and hatching rate among the dietary treatments. The highest (P < 0.05) fry survival rate was recorded in T1, followed by T3 and T4. Thus, it is suggested that control diet i.e. mixed zooplankton exhibited better growth, reproductive performance and fry survival rate. However, diet containing 400 g kg^?1 crude protein also gave comparable results in terms of growth, survival and reproductive performance of zebrafish.     

Effects of dietary Leucas aspera levels on growth performance,nutrient utilization,digestive enzymes and physio-metabolic and health status of bagrid catfish,Rita rita (Hamilton, 1822)

The study was to examine the effects of dietary L. aspera on growth performance, physio-metabolic response and health status of Rita rita fish reared in tanks for 60 days. Six experimental diets were formulated containing 0 g/kg, 3 g/kg, 6 g/kg, 9 g/kg and 12 g/kg L. aspera and designated as D0, D3, D6, D9 and D12 respectively. The inclusion of L. aspera at graded levels resulted in significantly varying effects on growth performance where the weight gain (%), specific growth rate (SGR) and feed conversion efficiency (FCE) were significantly higher (p<0.05) in D6 and D9 groups than others. The protease and amylase activities were elevated in L. aspera supplemented groups than the control group (p<0.05), whereas lactate dehydrogenase, malate dehydrogenase and serum transaminase enzyme activities were significantly reduced with the increasing level of L. aspera and comparatively higher activities of the respective enzymes were found in the control group. The activities of oxidative stress enzymes were significantly higher (p<0.05) in the D9 group and lower in control. The blood glucose level significantly decreased with the increasing level of L. aspera in the experimental diets. The L. aspera supplemented fish had significantly higher liver glycogen, serum protein, albumin and globulin than control group. Red blood cell count was significantly higher (p<0.05) in D6-D12, whereas white blood cell count and haemoglobin content were significantly higher (p<0.05) in D6 and D9 groups. Regression analysis showed that L. aspera at the level of 7.3–7.9 g/kg is optimum for better growth and feed efficiency.     

Evaluation of dietary protein requirement for the growth performance of minor carp,Cirrhinus reba (Hamilton, 1822) fingerlings

An experiment was designed to evaluate the requirement of dietary protein for Reba carp, Cirrhinus reba fingerlings using semi‐purified diet. Five isocaloric diets were prepared containing 20%, 25%, 30%, 35% and 40% level of protein using casein, gelatin as a major protein source. The experiment was conducted for 105 days in triplicates to evaluate the growth, survival, feed utilization, carcass composition of C. reba. Mean weight gain was highest (p < .05) in T3. Specific growth rate was highest in T3 and lowest in T1. Similarly, significantly (p < .05) highest net fish yield were recorded in T3. No significant difference was recorded in survivability. Feed conversion ratio, protein efficiency ratio, feed conversion efficiency and protein conversion efficiency were significantly (p < .05) higher for T3 compared with other treatments. Highest carcass protein and lipid values were recorded in T3. So, conclusion can be drawn that 30% crude protein is optimum for overall performance. Furthermore, broken‐line analysis for specific growth rate, final biomass and net fish yield indicated that dietary protein level of 28.148 to 28.253% is optimum for the best growth performance of fingerling C. reba.     

The effects of synthetic pigments on pigmentation of Pethia conchonius (Hamilton, 1822)

This study evaluated the effects of diets containing 20, 40, 60, 80 and 100 mg kg^?1 diet astaxanthin or canthaxanthin on Pethia conchonius (Hamilton, 1822) pigmentation. A completely randomized experimental design was developed with ten treatments and three replicates. Three hundred rosy barb with a mean weight of 0.92 ± 0.06 g were assigned to thirty aquaria for period of eight weeks. Carotenoid contents of fish fed canthaxanthin were always lower than those fed astaxanthin. Yellowness (b*) was not affected by pigments. While Luminosity (L*) decreased in fish fed astaxanthin diets, this parameter increased by feeding on canthaxanthin. The most pronounced effect was higher a* values in fish fed astaxanthin. Astaxanthin retention rate was higher than that of canthaxanthin. The present results demonstrate that canthaxanthin cannot be considered as a proper replacement with astaxanthin. Inclusion of 80 and 100 mg astaxanthin kg^?1 diet can be suitable dietary levels to ensure pigmentation and this condition may improve market value of rosy barb.     

Digestibility,growth and pigmentation of astaxanthin,canthaxanthin or lutein diets in Lake Kurumoi rainbowfish,Melanotaenia parva (Allen) cultured species

New cultured ornamental fish namely Lake Kurumoi rainbowfish Melanotaenia parva (Allen) run into reduced of colour performances when reared in the aquaria, consequently, fish feed must be added with carotenoids as a pigment source. The aim of this study was to evaluate the digestibility, growth and pigmentation of astaxanthin, canthaxanthin and lutein in diet. Apparent digestibility coefficients (ADC) of dry matter, lipid, protein, carotenoids, growth and pigmentation were studied in twenty fish after 14 and 56 days of observation. The single‐dose supplementation of 100 mg/kg of astaxanthin, canthaxanthin, or lutein diets on fish was fed by apparent satiation. The basal diet without carotenoids was used as control. The result showed that the ADC of carotenoids of test diets was higher compared to control. Fish fed astaxanthin diet had higher survival rate (96.67 ± 2.89%), colour measurements of lightness (57.60 ± 7.46%), a*‐values (4.66 ± 1.20), total carotenoids content in skin (33.75 ± 5.02 mg/kg) and muscle (2.16 ± 0.74 mg/kg). Astaxanthin also increased the growth after 14 days (2.00% ± 0.19%/days) but there was no significantly different at the end of experiment. The yellowish‐orange colour performance was more rapidly achieved by fish fed astaxanthin diet after 28 days experimentation. These values suggested that dietary carotenoids were required and astaxanthin diet was superior to other diets for skin pigmentation of Lake Kurumoi rainbowfish.     

Growth and survival of olive barb,Puntius sarana (Hamilton 1822) larvae produced with cryopreserved versus fresh sperm

Despite the success in fertilization and hatching of fish eggs with cryopreserved sperm, report on growth and survival of larvae produced from frozen‐thawed sperm is inadequate. The study evaluates the applicability of cryopreserved sperm for mass seed production by comparing the growth and survival of a popular food‐fish olive barb, Puntius sarana (Hamilton 1822) larvae produced from cryopreserved and fresh sperm. The eggs were artificially fertilized with cryopreserved and freshly collected sperm, and the growth and survival of produced larvae from both group recorded up to 12 weeks. The independent sample t‐test statistic showed the difference in lengths, t(718) = 0.241; P = 0.810 and weights, t(718) = 0.412; P = 0.680 were insignificant between two groups. There was also no significant difference, t(718) = ?0.758, P = 0.448 in survival of larvae produced from cryopreserved and freshly collected sperm. The study indicates that larvae of olive barb produced from cryopreserved sperm are equally compatible in growth and survival as the larvae produced from fresh sperm. Therefore, cryopreserved sperm can be applied for artificial fertilization of P. sarana to supply quality seed for aquaculture.     

Effects of dietary zinc oxide and selenium nanoparticles on growth performance,immune responses and enzyme activity in rohu,Labeo rohita (Hamilton)

A 120‐day feeding trial was conducted to assess the effects of dietary supplementation of zinc oxide (ZnO) and selenium (Se) nanoparticles (NPs) on growth, immunological and enzymatic profiles in rohu, Labeo rohita. Fishes were fed with basal diet incorporated with laboratory‐synthesized nanoparticles, viz., zinc oxide nanoparticles—10 mg/kg and Se nanoparticles—0.3 mg/kg throughout the experimental period. At an interval of every 30 days, treated and control fishes were randomly collected and subjected to estimation of growth, non‐specific immune parameters and serum enzyme assays. It was observed that there was significant (p < 0.05) increase in growth and non‐specific immune parameters like respiratory burst, lysozyme and myeloperoxidase activities as compared to the control group (only basal diet). Serum enzymatic profiles such as lactate dehydrogenase and alkaline phosphatase activities down‐regulated (p < 0.05) in treated group compared to control group, and superoxide dismutase and acetylcholine esterase activity up‐regulated in treated group. The relative percentage survival (RPS) found to be significantly higher in treated groups (60.00 ± 8.82%) as compared to control group (45.00 ± 6.17%) while challenged with virulent bacterial strain Aeromonas hydrophila. These results indicated that dietary supplementation of zinc oxide (ZnO) and selenium (Se) nanoparticles stimulates immunity and enhances resistance to bacterial infection in L. rohita.     

Suitable dietary chitosan improves the growth performance,survival and immune function of tiger shrimp,Penaeus monodon

Different levels of dietary chitosan on growth performance, survival and stress tolerance to air exposure was studied in tiger shrimp, Penaeus monodon. Shrimp (mean initial wet weight about 1.16 g) were fed with six different diets (C0, C0.05, C0.1, C0.2, C0.3 and C0.4) containing six level of chitosan (0%, 0.05%, 0.1%, 0.2%, 0.3% and 0.4% respectively) in triplicate for 60 days. Growth performance [final body wet weight (FBW); weight gain (WG); biomass gain (BG)] of shrimp fed chitosan‐containing diets were higher (P < 0.05) than that of shrimp fed the basal diet, shrimp fed C0.1 diet showed the highest value of growth performance. Survival of shrimp in C0.1 and C0.2 diet groups were higher (P < 0.05) than that of shrimp in C0, C0.05 and C0.4 diet groups but without statistical difference (P > 0.05) in shrimp fed C0.3 diet group. Whole body and muscle lipid contents decreased with increasing dietary chitosan levels. Plasma total cholesterol and triglyceride contents of shrimp fed C0 diet was significantly higher (P < 0.05) than that of shrimp fed chitosan‐containing diets. Plasma alanine aminotransferase (ALT) and aspartate aminotransferase (AST) activities of shrimp fed C0 diet were higher than those of shrimp fed chitosan‐containing diets. Digestive gland malondialdehyde (MDA) and carbonyl protein contents of shrimp fed chitosan‐containing diets were lower (P < 0.05) than that of shrimp fed C0 diet. Total haemocyte count of shrimp fed C0 diet was lower (P < 0.05) than that of shrimp fed chitosan‐containing diets. On the contrary, the haemolymph clotting time of shrimp fed C0 diet was higher (P < 0.05) than that of shrimp fed chitosan‐containing diets. In conclusion, all results suggested that dietary intake containing 0.1% and 0.2% chitosan enhanced the growth of shrimp, whereas a higher level than 0.3% and 0.4% decreased growth of shrimp. Second‐degree polynomial regression analysis of WG and BG indicated that the optimum supplement of dietary chitosan level should be 0.19–0.21%.     

Effects of dietary microbial levan on growth performance,RNA/DNA ratio and some physio‐biochemical responses of Labeo rohita (Hamilton) juveniles

Six isonitrogenous and isocaloric semi‐purified diets were prepared with different levels of microbial levan: control (Basal), T1 (Basal + 2.5 g kg^?1 diet), T2 (Basal + 5 g kg^?1 diet), T3 (Basal + 7.5 g kg^?1 diet), T4 (Basal + 10 g kg^?1 diet) and T5 (Basal + 12.5 g kg^?1 diet), fed to six groups of fish in triplicate tanks. The results of the 60 days feeding trail showed that supplementation of dietary levan significantly affected the weight gain percentage and specific growth rate of the treatment groups fed at 10 g kg^?1 or more levan. Lowest feed conversion ratio (FCR) value and highest survival percentage among levan fed groups were observed with 12.5 g kg^?1 incorporation (T5) and was comparable with (T4) group. Significant increase in muscle RNA level and RNA/DNA ratio was observed with the increasing dietary levan. Fish fed 12.5 g kg^?1 levan had significantly higher protease, amylase and lipase activities compare with the control group. Lowest Aspartate aminotransferase (AST) activity in the liver and muscle was observed in the T5 group fed with highest level of dietary levan. Overall results conclude that dietary microbial levan incorporation at 12.5 g kg^?1 could be used as potent dietary prebiotic for the culture of L. rohita juveniles.     

Effect of dietary Clostridium butyricum and different feeding patterns on growth performance,antioxidant and immune capacity in freshwater prawn (Macrobrachium rosenbergii)

An 8‐week study was conducted to evaluate the effects of different feeding patterns with dietary Clostridium butyricum supplementation on growth performance, antioxidant and non‐specific immune responses in freshwater prawn, Macrobrachium rosenbergii (0.39 ± 0.001 g). There were four feeding methodologies: feeding basal diet continuously (P1); feeding diet with 500 mg/kg C. butyricum continuously (P2); feeding diet with 500 mg/kg C. butyricum 5 days after 2 days of basal diet (P3) and feeding diet with 500 mg/kg C. butyricum 2 days after 5 days of basal diet (P4). The results revealed that prawns in P3 had the highest weight gain rate (WGR) and lowest feed conversion ratio (FCR) than the other groups. Haemolymph total protein levels and superoxide dismutase activity increased significantly in P2, P3 and P4 groups, while malondialdehyde content and anti‐superoxide anion levels decreased significantly compared to control. The mRNA expression of intestinal dorsal and Toll in P2 and P3 groups decreased significantly compared to control. Prawns in P3 exhibited improved growth performance, increased antioxidant capacity and enhanced immune function. We concluded that feeding diet with 500 mg/kg C. butyricum for 5 days after 2 days of basal diet was recommended for M. rosenbergii.     

Establishment and characterization of macrophage cell line from thymus of Catla catla (Hamilton, 1822)

A continuous cell line has been developed from thymus explants of Catla catla and the cells have been subcultured for 63 passages. The cells exhibited optimum growth at 30°C in L‐15 medium containing 15% foetal bovine serum. The cultured cells engulfed yeast cells and fluorescent latex beads. These cells produced reactive oxygen and nitrogen intermediates following stimulation with lipopolysaccharide and phorbol esters. The culture supernatant from the cultured cells had lysozyme activity and these cells demonstrated Fc receptors. Almost all the cells were positive for alpha‐naphthyl acetate esterase enzyme suggesting that the cells are of macrophage lineage and therefore, the cell line was designated as catla thymus macrophage (CTM) cell line. CTM cells formed aggregates around zoospores of Aphanomyces invadans, but were unable to inhibit the germination of spores. The karyotype analysis of CTM cells at 25th passage revealed a typical diploid model with 50 chromosomes per cell. Partial amplification, sequencing and alignment of fragments of two mitochondrial genes 16S rRNA and cytochrome c oxidase subunit 1 confirmed that the CTM cell line originated from C. catla. This cell line should be useful for studying the role of macrophages in differentiation and maturation of thymocytes and can be a source of macrophage‐specific enzymes and cytokines.     

Effects of Spirulina platensis as a feed additive on growth and coloration of blue dolphin cichlids (Cyrtocara moorii Boulunger, 1902)

This study was carried out to investigate the effects of replacing fish meal with dietary Spirulina as a feed supplement on the growth performance and coloration of blue dolphin cichlids (Cyrtocara moorii). Five isonitrogenous (47% crude protein) and isocaloric (17.36 kJ/g digestible energy) diets were for formulated to replace FM with 0, 5, 10, 15 and 20% Spirulina (designated as Control, SP5, SP10, SP15 and SP20 respectively) and fed to the fish (initial body weight, 3.15 ± 0.01 g). Fish were randomly distributed into fifteen 120 L aquariums (26.5 ± 1.00°C), 15 fish per aquarium. The diets were tested in triplicate for 12 weeks. Experimental groups were fed twice daily (09:00 and 17:00) by hand to satiation. At the end of the feeding trial, significantly (p < 0.05) higher weight gain (WG), specific growth rate (SGR), protein efficiency ratio (PER) and lower feed conversion ratio (FCR) were observed in fish fed the SP10 diet when compared to the SP20 diet. There was no significant difference in these parameters between the other groups. The skin coloration of blue dolphin cichlid fed a diet containing Spirulina meal was enhanced. The best coloration was observed in the SP15 group. These impressions were objectively validated by chemical determinations of carotenoids extracted from fish skins and passed statistical tests of significance. The study findings show that Spirulina meal does not diminish growth rates except at very high levels.     

Effect of dietary supplementation of calcium chloride on growth,survival, moulting frequency and body composition of narrow‐clawed crayfish,Astacus leptodactylus (Eschscholtz, 1823)

The effects of dietary calcium chloride (CaCl₂) concentration on the growth, survival, moulting and body composition of Astacus leptodactylus were studied. Diets were prepared using supplementation of 0 (control), 30, 60 and 120 g kg^?1 calcium chloride commercial trout larvae diet containing 50% protein and 12% lipid. Astacus leptodactylus larvae with an average total length of 22.0 ± 0.05 mm (TL) and weight of 0.53 ± 0.01 g obtained from eighteen ovigerous females collected from Seydisehir Sugla Dam lake in Konya, Turkey, were stocked in 0.2‐m² aquariums at a rate of 50 crayfish m^?2 and reared for 90 days. The experiments included four treatments (diets) with three replicates each. Calcium chloride exerted positive effects on growth, moulting frequency, feed efficiency and survival of narrow‐clawed crayfish. Crayfish fed with 60 g calcium kg^?1 calcium chloride‐supplemented diet exhibited the highest weight gain and specific growth rate (SGR) but the lowest survival rate (63.3%) (P < 0.05). There were no significant differences (P > 0.05) in mean moisture (803.5 g kg^?1) and protein content (177.0 g kg^?1) in crayfish tail meat. However, lipid values were between 3.8 and 11.6 g kg^?1 and significantly different among the diets (P < 0.05). Diet with 60 g kg^?1 calcium chloride is recommended for the best growth of freshwater crayfish.     

Length–weight relationship and growth performance of different life stages of hatchery‐produced magur,Clarias magur (Hamilton, 1822)

Length–weight relationship (LWR) of 661 numbers of hatchery‐produced magur, Clarias magur of all the life stages such as hatchlings, fry, fingerlings, juveniles and adults, was studied. The LWR of all the life stages of magur was estimated and the equations are as follows, hatchlings W = 0.0052*L^1.282 (r² = 0.8784), fry W = 0.0088*L^3.028 (r² = 0.8113), fingerlings W = 0.0065*L^3.226 (r² = 0.8906), juveniles W = 0.0028*L^3.420 (r² = 0.8175) and adults W = 0.0017*L^3.491 (r² = 0.8310). A positive allometric growth (b > 3) was observed in all the life stages except hatchlings. The annual growth rate of magur was observed with the body length and weight of 24 ± 1 cm and 115 ± 17 g, respectively, under the commercial production system. This is the first kind of study that describes about the LWR and growth performance of all the life stages of hatchery‐produced C. magur catfish from hatchlings to adults under commercial production system. This study will be more useful to the hatchery managers and fish growers to optimize the resources and husbandry practices to improve the growth, survival, and biomass production.     

Lutein as a natural carotenoid source: Effect on growth,survival and skin pigmentation of goldfish juveniles (Carassius auratus)

This study aimed to evaluate the effect of lutein supplementation on growth, survival and skin pigmentation for goldfish juveniles. Four diets enriched with different carotenoid sources (lutein, astaxanthin, canthaxanthin and a combination of lutein and canthaxanthin) were compared to a control diet without carotenoid supplementation. The carotenoid inclusion level was standardized at 50 mg kg‐1 in all treatments. 240 goldfish juveniles (1.07?0.57 g) were cultivated in 30 aquariums (30L) during 84 days. The experimental design was completely randomized with five treatments and six replicates. The dietary inclusion of carotenoid pigments did not affect the growth and feeding efficiency of goldfish juveniles. Supplementation with lutein presented higher survival values when compared to the other treatments. Astaxanthin and canthaxanthin supplementation increased the concentration of carotenoids on the skin of goldfish juveniles in relation to the control treatment. For the fish fed with the diet containing lutein, the skin pigmentation was as efficient as astaxanthin and canthaxanthin, but did not differ from the control and combined treatment (canthaxanthin + lutein). The lutein supplementation (50 mg kg‐1) improved survival and promoted efficient carotenoid pigmentation on the skin of goldfish juveniles.     

Effects of dietary astaxanthin and vitamin E and their interactions on the growth performance,pigmentation, digestive enzyme activity of kuruma shrimp (Marsupenaeus japonicus)

A 56‐day feeding trial was done to investigate the interactive effects of astaxanthin (Ax) and vitamin E (α‐Toc) on the performance of kuruma shrimp (Marsupenaeus japonicus). A 2 × 3 factorial experiment was conducted with six experimental diets containing two levels of Ax (0 and 0.6 g/kg diet [Ax₀ and Ax_0.6]) and three levels of α‐Toc (0, 0.2 and 1 g/kg diet [α‐Toc₀, α‐Toc_0.2 and α‐Toc₁]). The results indicated that growth performance was significantly (p < 0.05) increased in shrimp fed with the Ax_0.6 × α‐Toc_0.2 diet. Interactive effects between Ax and α‐Toc on the growth parameters were observed. Furthermore, pigmentation performance was significantly (p < 0.05) better in the Ax_0.6 groups. Interaction between Ax and α‐Toc was also found in the Ax content of shrimp body parts. Interestingly, dietary α‐Toc helped to reduce the Ax consumption rate, promote the absorption and increase the deposition of Ax in the muscle. Shrimps from the Ax_0.6 groups showed significantly (p < 0.05) improved hepatopancreatic digestive enzyme activities compared with those of the Ax₀ groups. Although no interactive (p > 0.05) effects were found between dietary α‐Toc and Ax on total haemocyte count and tolerance against freshwater, dietary Ax and α‐Toc supplementation showed better performance on these two parameters. It was concluded that dietary Ax and α‐Toc functioned synergistically, and the shrimp fed with the diet containing 0.6 g Ax/kg diet Ax and 0.2 g α‐Toc/kg diet showed improved growth and pigmentation performance compared with the other groups in the current study.     

Dietary administration of natural immunostimulants on growth performance,haematological, biochemical parameters and disease resistance of Asian Sea bass Lates calcarifer (Bloch, 1790)

This study was aimed to address the promising evaluation of Cissus quadrangularis plant (stem) and lipopolysaccharide (LPS from bacteria) supplemented diets on innate immune response in Lates calcarifer fingerlings against Aeromonas hydrophila infection. Fingerlings were fed supplemented diets containing four different concentrations of C. quadrangularis (0.5, 1.0, 1.5 and 2.0 g kg^?1 feed), LPS (25, 50, 75 and 100 mg kg^?1 feed) and control (normal formulated diet) for 60 days. The fish fingerlings fed supplemented diet displayed significant differences (P < 0.05) in specific growth rate (SGR) and relative percentage survival compared to the control group fed without C. quadrangularis and LPS‐supplemented diet. Fingerlings were injected intraperitoneally with 100 μL lethal dose of A. hydrophila containing 1 × 10⁶ CFU g^?1. Supplementation of C. quadrangularis and LPS diet significantly increased biochemical profile such as protein, lipid and carbohydrate content, haematological parameters of L. calcarifer fingerlings in different experimental periods when compared with the control group. Dietary doses of C. quadrangularis and LPS‐supplemented diet significantly influenced growth performance and increased survival rate in L. calcarifer fingerlings against A. hydrophila infection.     

Effects of dietary fishmeal replacement with Spirulina platensis on the growth,feed utilization,digestion and physiological parameters in juvenile gibel carp (Carassis auratus gibelio var. CAS III)

A 60‐day growth experiment was conducted to investigate the effect of dietary replacement of fishmeal by Spirulina platensis on growth performance, digestion and physiological parameters in juvenile gibel carp (5.0 ± 1.0 g). Four diets were formulated to replace 0 (SP0), 50% (SP50), 75% (SP75) and 100% (SP100) of dietary fishmeal protein by S. platensis respectively. Other two diets based on SP100 were supplemented with 2% dicalcium phosphate (SP100 + P) or 0.28% coated lysine (SP100 + Lys). The results showed that no significant differences of specific growth rate (SGR), feed efficiency (FE), feeding rate (FR) and protein efficiency ratio (PER) were observed between SP0 group and the replacement groups (SP50, SP75 and SP100). FE and PER of fish‐fed SP100 + Lys diet were significantly higher than the fish‐fed SP100 diet (p < .05). Apparent digestibility coefficients (ADCs) of dry matter, protein, energy and phosphorus increased significantly with the increasing S. platensis inclusion. Meanwhile, fish from SP100 + P or SP100 + Lys group had higher ADCs of nutrients compared to the SP100 group (p < .05). Compared with SP0 diet, fish‐fed S. platensis diets had higher activities of plasma superoxide dismutase, hepatopancreas total antioxidant capacity, plasma alkaline phosphatase and plasma lysozyme, as well as the lower content of plasma malondialdehyde. The present results indicated that dietary fishmeal could be fully replaced by S. platensis without any negative effects on growth performance of gibel carp. Supplementation of lysine in the S. platensis replacement diet could further improve the feed utilization of gibel carp.