Replacement of fish meal with rapeseed protein concentrate in diets fed to wels catfish (Silurus glanis L.)

The potential of rapeseed protein concentrate as fish meal alternative in diets for wels catfish (initial average weight 86.5 ± 1.9 g) was evaluated. Sixteen fish were stocked into each of 12 experimental tanks being part of a freshwater recirculation system. Fish were organized in triplicate groups and received isonitrogenous (603 ± 3 g CP kg^?1) and isocaloric (23.0 ± 0.3 kJ g^?1) experimental diets with 0%, 25%, 50% and 75% of fish meal replaced with rapeseed protein concentrate (710 g CP kg^?1). At the end of the 63‐day feeding period, weight gain, standard growth rate, feed intake, feed conversion ratio and protein efficiency showed no significant difference between control group and fish fed on diets with 25% reduced fish meal content by inclusion of rapeseed protein concentrate. Higher dietary fish meal replacement negatively affected diet quality and palatability resulting in reduced feed intake, feed efficiencies and fish performance. However, blood serum values of triglycerides, glucose and protein were not significantly different between treatment groups, still indicating a favourable nutrient supply from all experimental diets.     

Dietary substitution of soy and rapeseed protein concentrates for fish meal, and their effects on growth and nutrient utilization in gilthead seabream Sparus aurata L.

Soy and rapeseed protein concentrates (SPC and RPC) were evaluated as fish meal substitutes in gilthead seabream Sparus aurata L. diets. The protein concentrates were used to replace 30%, 60% and 100% fish meal, and effects on feed intake, weight gain and feed gain ratio were determined in a 56‐day growth trial. Some groups were then grown beyond 56 days, until all reached an average weight of 50 g. A comparison of body composition at 50 g showed no significant differences in protein and ash content among all fish, while lipid and energy contents were different. The 100% RPC and 60% and 100% SPC replacement diets had lower body lipid and energy contents compared with those of the control diet. Feed intake and weight gains were inversely related to inclusion levels of plant proteins. Feed intake dropped to 52–72% of that of the control treatment and weight gain to 46–61%. Energy retention followed this same trend, decreasing from ERV values of 53 to 44 with an increase in dietary plant protein content. With the exception of 100% SPC substitution (PPV = 35), protein retention among treatments was similar (PPV = 37–39). These results suggest that both SPC and RPC may be promising protein sources for inclusion in seabream diets. The relative palatability of these plant proteins could be a limiting factor in their use.     

Effects of five compound attractants in high plant‐based diets on feed intake and growth performance of juvenile turbot (Scophthalmus maximus L.)

An experiment was conducted to evaluate the effects of five attractants on feed intake, growth performance and appetite‐regulating genes expression for juvenile turbot (Scophthalmus maximus L.). Fish were fed with seven diets: fish‐meal‐based diet (FM), fermented soybean meal replacing 45% fish meal (FSBM) and other diets with 1% compound attractant A (CA‐A) consisting of amino acids, compound attractant B (CA‐B) consisting of quaternary ammonium bases, compound attractant C (CA‐C) consisting of nucleotides, compound attractant G (CA‐G) consisting of the combination of CA‐A, CA‐B and CA‐C and blue mussel protein hydrolysate (BMH) on the basis of FSBM diet respectively. Daily feed intake in CA‐A group was significantly higher, but that in CA‐B group was significantly lower than FSBM group. Similarly, specific growth rate was significantly enhanced in CA‐A and CA‐G groups and were significantly decreased in CA‐B group. Protein efficiency ratio and protein retention in CA‐B group were significantly lower than FSBM group. Furthermore, BMH supplement increased the mRNA expression of Ghrelin in the intestine of fish. These results showed that CA‐A and CA‐G supplement could enhance growth in plant‐based diets, but CA‐B supplement had the opposite effect, which might be associated with lower feed intake and lower feed utilization.     

利用豆粕、菜粕和棉粕替代饲料中鱼粉对苏氏圆腹鱼芒摄食、生长和饲料利用的影响

摘要：通过8周网箱实验评价了利用豆粕、菜粕和棉粕作为苏氏圆腹鱼芒 （Pangasius sutchi）饲料中鱼粉替代蛋白源的潜力。配制了7种等氮、等能饲料,其中基础饲料含45%鱼粉,按等量蛋白替代的原则,在其余6种饲料中分别添加31%和46%豆粕替代基础饲料中鱼粉的50%和75%,或添加20%和40%菜粕替代基础饲料中鱼粉的25%和50%,或添加19%和39%棉粕替代基础饲料中鱼粉的25%和50%。实验中所用的苏氏圆腹鱼芒初始体重为11.3 g。实验结果表明：添加豆粕将饲料中鱼粉含量从45%降低到23%,添加菜粕或棉粕将鱼粉含量降低到34%,对鱼成活率、摄食、鱼体增重、特定生长率（SGR）、饲料系数（FCR）、饲料蛋白储积率、脏体指数和红血细胞比积（Hct）未产生显著不良影响。添加豆粕将鱼粉含量降低到11%导致鱼摄食、鱼体增重和SGR下降,添加菜粕将鱼粉含量降低到23%导致FCR和鱼体能量储积率下降,添加棉粕将鱼粉含量降低到23%导致鱼体增重、SGR和Hct明显下降。上述结果显示,可通过添加豆粕（31%）将苏氏圆腹鱼芒 鱼种饲料中鱼粉含量降低到23%,或通过添加菜粕（20%）和棉粕（19%）将饲料中鱼粉含量降低到34%。     

Pacific hake (Merluccius productus Ayres, 1855) hydrolysates as feed attractants for juvenile Chinook salmon (Oncorhynchus tshawytscha Walbaum, 1792)

Soybean meal (SBM) inclusion in salmonid diets can lower feed cost, but dramatically reduces growth and feed utilization, and increases mortality in juvenile chinook salmon Oncorhynchus tshawytscha, due to diminished diet palatability and/or other adverse physiological effects exerted by antinutritional factors in SBM. The objective of this study was to investigate whether commercial Antarctic krill meal Euphausia superba or hydrolysates enzymatically produced from Pacific hake Merluccius productus could reverse the negative palatability effects of SBM inclusion in juvenile chinook salmon diets. Diets without SBM or with SBM and no added feed attractant were used as positive and negative control diets respectively. Incorporation of 2% krill meal or Alcalase^®‐produced hydrolysates into SBM‐containing diets (20% of dry matter by isonitrogenous replacement of fishmeal) significantly (P < 0.05) increased feed intake, feed utilization, fish weight gain and thermal growth coefficient during a 5‐week trial. Nevertheless, the negative effects on fish performance incurred by dietary inclusion of 20% SBM could not be fully reversed, indicating that most of those effects were likely unrelated to palatability. This study demonstrates the potential for using Pacific hake hydrolysates as a dietary feed attractant for salmonid diets, and supports the need for further research to optimize its application for ideal fish performance.     

Fishmeal replacement by mixed plant proteins and effect on growth and sensory attributes in on‐growing turbot

Fishmeal replacement with a mixture of plant protein (PP) raw materials (soya, wheat gluten meal, corn gluten meal and rapeseed meal) in diets for 300‐950 g turbot was tested. Eight different diets with fishmeal protein stepwise varying from 53.7% of crude protein (CP) to 93% of CP of the total protein in the diet were tested. The fish was weighed at monthly intervals for following of weight development and calculation of specific growth rates, daily feed intake and feed conversion ratio. At the end of the experiment, fish was sampled for sensory evaluation. Average final weight was 950 g and did not vary between the experimental groups. There were no effects of dietary treatment on specific growth rates, daily feed intake, feed conversion ratio or sensory attributes measured. The least‐cost diet (with 53.7% fishmeal protein) is about 12% lower in raw material cost (based on material price of diet components) than the all fishmeal diet. The results therefore indicate that the raw material cost in feed for on‐growing turbot can be reduced considerably without any negative effect on growth and feed utilization.     

Partial replacement of fish meal by porcine meat meal in practical diets for Pacific white shrimp (Litopenaeus vannamei)

In this study, it evaluated the growth performance of the Pacific white shrimp Litopenaeus vannamei in response to the replacement of fish meal with rendered porcine meat meal (PMM) in its diet. Six isolipidic and isonitrogenous diets were formulated with 0, 25, 35, 45, 55 or 65% replacement of fish meal with PMM on a protein basis. Shrimp grew from 0.55 g to > 3.6 g during the 41-day experimental period. Specific growth rate (SGR) was significantly lower when PMM inclusion was 26.18% or greater, replacing more than 45% fish meal protein. A significant negative relationship was observed between growth response and the level of fish meal protein replacement with PMM protein. Methionine content decreased as PMM inclusion levels increased, consequently compromising growth performance. Dry feed intake (DFI) and the feed conversion ratio (FCR) were unaffected by fish meal replacement levels. The protein efficiency ratio (PER) was highest at the lowest PMM inclusion level. Apparent protein digestibility coefficient (APDC) for PPM was 66.2%. Experimental diets D-0 and D-25 had apparent dry matter digestibility (ADMDs) ranging from 77–81% and ADPs from 82–85%, while the diets with higher PMM inclusion (D-35 to D-65) had a significantly lower ADMD range (70–72%) and APD range (73–78%). It is concluded that porcine meat meal is an acceptable alternative animal protein source that can replace up to 35% of fish meal protein in shrimp diets without significant adverse effects on growth, survival, FCR, PER and body composition.     

Replacement of fishmeal with rice protein concentrate in practical diets for European sea bass Dicentrarchus labrax reared at winter temperatures

As no information is available regarding the efficacy of using rice protein concentrate (RPC) to replace fishmeal (FM) in diets for European sea bass (Dicentrarchus labrax), a trial was conducted to determine the optimum inclusion for European sea bass juveniles. Diets were formulated to replace 25%, 50% and 75% of fishmeal with RPC. Additional high level inclusion diets (50% and 75%) were supplemented with lysine and methionine to determine if these were limiting factors. Fish (18.0 ± 0.06 g) were fed the experimental diets for 12 weeks. The final mean weight and specific growth rate (SGR) were significantly higher in fish fed the control diet (diet FM) and low level RPC (diet RPC25) than in fish fed the other diets. The supplementation of the amino acids had a positive effect on growth, elevating the final weight of the high level RPC (RPC75 + AA) group above that of the non‐supplemented group (RPC75). However, this was still not comparable to fish fed FM and RPC25 diets. No significant differences in body composition were observed. A digestibility study demonstrated an inverse relationship between elevating inclusion levels of RPC and apparent digestibility coefficients (ADCs) for dry matter and lipid, with significantly lower values than the control being observed with RPC inclusions above 25%. The mesenteric fat index followed this trend. Circulating leucocyte levels, leucocyte ratios and serum lysozyme activity remained unaffected by dietary treatment. However, compared with the control group, fish fed RPC75, RPC50 + AA RPC75 + AA displayed significantly lower haematocrit values. The present study demonstrates that the inclusion of RPC at 140 g kg^?1 (effectively replacing 25% of FM content) does not compromise European sea bass growth performance, body quality or basic haematological parameters. It is suggested that future studies including higher levels test the efficacy of additional amino acid supplementation (e.g. tryptophan).     

Validation of processed animal proteins (mono‐PAPS) in experimental diets for juvenile gilthead sea bream (Sparus aurata L.) as primary fish meal replacers within a European perspective

Experimental diets were formulated to evaluate a “pure” poultry meat meal (PMM) source in diets formulated for juvenile gilthead sea bream (Sparus aurata L.). The digestible protein contribution of fish meal in a control diet was substituted by 25%, 50% and 75% of a processed poultry meat meal (PMM) on a digestible crude protein (DCP) basis and by 5% and 10% for an enzyme‐treated feather meal (EFM) and also a spray‐dried haemaglobin meal (SDHM), respectively. In a consecutive trial, diets were designed to assess the value of a “pure” (defatted) poultry protein substituting the fish meal (FM) protein content. Experimental diets included: a control diet, two test diets where 75% of FM was replaced by a full‐fat PMM (PMM75) or a defatted grade of PMM (dPMM75) and two test diets where 50% of FM was substituted for defatted PMM (dPMM50) or a 50:50 blend of soya bean meal and defatted PMM (SBM/dPMM) to produce a composite product. This soya bean/dPMM blend was tested to enhance the nutritional value of this key plant ingredient commonly employed in sea bream diets that can be deficient in specific amino acids and minerals. In the first trial, gilthead sea bream grew effectively on diets containing up to the 75% replacement of FM attaining a mean weight of 63.6 g compared to 67.8 g for the FM control fed group. For the consecutive trial, the fishmeal‐based control diet yielded the highest SGR followed by dPMM50 and SBM/dPMM blend inclusion but was not significant. Carcass FA profiles of gilthead sea bream conformed to the expected changes in relation to the dietary FA patterns, with the 18:1n‐9 representative of the poultry lipid signature becoming more apparent with PMM inclusion. The ratio of n‐3/n‐6 fatty acids was greatly affected in sea bream fed the full‐fat PMM at 75% inclusion due to fish oil exclusion. Defatted dPMM, however, allowed more of the fish oil to be used in the diet and reducing this latter effect in sea bream carcass, hence restoring the higher total omega‐3 HUFA fatty acids namely EPA and DHA and n‐3/n‐6 ratio. It is concluded that poultry meat meal can be modestly incorporated into formulated diets for sea bream and can be used in conjunction with soya bean meal without any fundamental changes in performance and feed efficiency.     

Growth, feed efficiency, digestibility and nutrient distribution in Atlantic cod (Gadus morhua) fed two different fish meal qualities at three dietary levels of vegetable protein sources

Atlantic cod were fed six diets where the ratio of protein from fish meal to vegetable protein were varied from 91%, 67% to 46%, respectively. The experimental groups were performed in triplicate in a 20 week growth trial, increasing fish weight from about 167 g to 690 g. The vegetable protein sources constituted full-fat soybean meal and corn gluten meal at a fixed ratio of 1:2, and replaced either a high quality fish meal (DC_Mink 92.3%) or a lower quality fish meal (DC_Mink 85.6%) in the diet. All diets were extruded and balanced to be equal in gross energy, crude protein, lipid, carbohydrate, lysine and phosphorus. No difference in growth (SGR 1%) was observed comparing the two fish meal qualities. However, feed intake was significantly higher (9%) and feed efficiency lower (10%) for lower quality fish meal compared to high quality fish meal. Protein and amino acid digestibility was significantly reduced in the lower quality fish meal, while unaffected by vegetable protein inclusion for both fish meal qualities. Protein utilization as measured by protein efficiency ratio and net protein value was not affected by fish meal inclusion, except in the diet using lower quality fish meal and high vegetable protein inclusion. Lipid and energy digestibility was significantly reduced by vegetable protein inclusion for both fish meals. The lower fish meal quality increased lipid deposition in the liver and affected slaughter quality of cod by increasing HSI and dressing out percentage at low and intermediate substitution levels. Muscle composition showed small dietary changes except for arginine, while liver fatty acid composition clearly reflected fatty acid profile of full-fat soya in the diets. Corn gluten meal and full-fat soybean meal (2:1) can replace approximately 50% of dietary protein without affecting feed intake, growth, protein digestibility or slaughter quality of cod when exchanging high quality fish meal. For the lower quality fish meal diets some lower inclusion of vegetable protein sources seem to be acceptable.     

Effect of Dietary Inclusion of Blue Mussel Extract on Growth and Body Composition of Japanese Flounder Paralichthys olivaceus

Dietary inclusion of a water-soluble fraction of blue mussel Mytilus galloprovincialis was examined as a feeding stimulant for juvenile Japanese flounder Paralichthys olivaceus . The control diet mainly consisted of fish meal, potato starch, and pollack liver oil. Five, 10, and 20% (weight/weight) of the control diet was exchanged with aqueous extracts of blue mussel meat in experimental groups. Fish of about 10 g in initial body weight were fed each diet to satiation, twice daily, 6 d per wk for 6 wk at 20 C. The final body weight, weight gain, and feed efficiency of fish fed the diets containing blue mussel extracts were significantly higher than those of fish fed the control diet. However, these parameters were not different among experimental groups containing blue mussel extract independent of the inclusion level of extract. A similar trend was shown in protein efficiency ratio as fish fed the control diet had a significantly lower protein efficiency ratio than the other dietary groups. Compared to the control diet, higher plasma protein and lower triglyceride were found in fish fed the diets with the extract, while other blood constituents were relatively similar for the dietary groups tested. On the other hand, whole-body crude lipid content and lipid retention of fish fed the diets with the extract were generally significantly higher than those of fish fed the control diet. Whole body crude protein was identical regardless of the dietary composition; however, protein retention of fish showed a similar trend to lipid retention.     

复合动植物蛋白部分替代鱼粉对大菱鲆幼鱼生长、体成分及生理生化指标的影响

本研究设计5组等氮等能(粗蛋白为53%,能量为25KJ/g)的实验饲料,以60%的鱼粉饲料组作为对照(D1),豆粕∶花生粕∶鱼溶浆粉∶鸡肉粉(2∶1∶3∶2)的复合蛋白替代40%(D2)、50%(D3)、60%(D4)和70%(D5)的鱼粉,养殖大菱鲆幼鱼(Scophthalmus maximus L.)初始体重(53.0±0.2) g,养殖周期84 d,每天定时(08:00,16:30)投喂2次,投喂量为体重的1.5%～2%。实验结果显示,各处理组之间幼鱼存活率、饲料系数和摄食率均无显著性差异(P0.05);与对照组相比,D4和D5组增重率显著降低(P0.05);肥满度在D2组达到最高值,显著高于D3、D4和D5组(P0.05);脏体比(VSI)、肝体比(HSI)和肠体比(ISI)均在D2组达到最低值,均显著低于D5组(P0.05);复合动植物蛋白替代鱼粉对大菱鲆幼鱼全鱼水分和粗蛋白含量均无显著影响(P0.05);各替代组全鱼粗脂肪含量显著高于对照组(P0.05);全鱼灰分含量在D5组显著低于对照组(P0.05);各组间背肌水分、粗蛋白、粗脂肪和灰分含量均无显著性差异(P0.05);复合动植物蛋白替代鱼粉对鱼体肌肉非必需氨基酸和必需氨基酸总量无显著影响(P0.05);各替代组均显著提高了血清谷草转氨酶和谷丙转氨酶活性(P0.05);总蛋白浓度在D2组显著高于D4和D5组(P0.05);血糖浓度在D2和D3组显著低于其他3组(P0.05);D3、D4和D5组甘油三酯浓度和高密度脂蛋白浓度均显著低于对照组和D2组(P0.05);各替代组胆固醇和低密度脂蛋白浓度均显著低于对照组(P0.05);各组之间碱性磷酸酶浓度无显著差异(P0.05)。研究结果表明,复合动植物蛋白可有效替代50%鱼粉而不影响大菱鲆幼鱼生长性能和部分生理生化指标。     

大豆浓缩蛋白替代鱼粉对大菱鲆摄食、生长及体组成的影响

研究了大豆浓缩蛋白(SPC)替代鱼粉对大菱鲆生长及生理生化指标的影响。5种饲料分别含有0、12.0%、25.0%、37.0%和49.5%的SPC以替代相应的鱼粉,并分别添加0、0.83%、1.65%、2.48%和3.30%的必需氨基酸混合物(L-lysine∶DL-methionine∶L-leucine∶Lvaline∶L-threonine=18∶6∶3∶2.5∶2)以平衡各组饲料的氨基酸组成。每种饲料投喂3个水族箱(300 L),每个水族箱放养实验鱼16尾,实验鱼初始体质量为(31.1±0.1)g。经过9周生长实验,结果显示随着饲料中SPC替代水平的升高,大菱鲆摄食率、特定生长率均显著下降(P0.001)。然而,当使用0~37.0%的SPC替代鱼粉时,各处理组饲料效率和蛋白质效率未出现显著差异(P0.05)。饲料中SPC替代鱼粉对大菱鲆鱼体水分、粗蛋白、粗脂肪及灰分含量均无显著影响(P0.05)。各处理组干物质和粗蛋白的表观消化率之间也未出现显著差异(P0.05)。研究表明,在本实验条件下SPC不能作为大菱鲆饲料中替代鱼粉的有效蛋白源,造成SPC替代效果较差的主要原因是其对大菱鲆饲料适口性的显著影响。     

Growth and Body Composition Effects of Tuna Byproduct Meal Substituted for Fish Meal in the Diet of Juvenile Abalone,Haliotis discus

The effects on growth and body composition that result from tuna byproduct meal (TBM) substituted for fish meal in the diet of juvenile abalone, Haliotis discus, were determined. One thousand two hundred sixty juvenile abalone were randomly distributed into 18 70‐L plastic rectangular containers. Six experimental diets were prepared in triplicate. The TBM0 diet included 28% fish meal and 13% soybean meal as the protein source. Twenty‐five, 50, 75, and 100% of the fish meal were substituted with TBM. Finally, salted sea tangle was prepared. The essential amino acids, such as isoleucine, lysine, and valine, tended to decrease with the dietary substitution of TBM for fish meal in the experimental diets. The weight gain and specific growth rate (SGR) of abalone that were fed the TBM25 diet were higher than those of abalone that were fed the other diets. The crude protein content of the soft body of the abalone linearly decreased with the dietary substitution of TBM for fish meal. In conclusion, as much as 75% of the fish meal in the diet of abalone can be replaced with TBM without retardation in weight gain and SGR of the abalone when 28% fish meal was included.     

Total fish meal replacement with rapeseed protein concentrate in diets fed to rainbow trout (Oncorhynchus mykiss Walbaum)

The potential of rapeseed protein concentrate as fish meal alternative in diets for rainbow trout (initial average weight 37.8?±?1.4?g) was evaluated. Nine experimental tanks of a freshwater flow-through system were stocked with 12 fish each. Triplicate groups of fish received isonitrogenous (47.9?±?0.5% CP) and isoenergetic (22.4?±?0.2?kJ?g^?1) experimental diets with 0, 66 and 100% of fish meal substituted with rapeseed protein concentrate (71.2% CP), thereby providing 0, 29 and 43% of dietary protein. As the amino acid profile of rapeseed protein concentrate was comparable to fish meal, there was no need to supplement experimental diets with synthetic amino acids. At the end of the 84?days of feeding period, fish growth performance, feed intake and feed efficiencies were not compromised, when 100% of fish meal in the control diet was replaced with rapeseed protein concentrate, revealing a SGR of 1.19 or 1.10, a FCR of 1.09 or 1.18 and a feed intake of 78.5 or 74.7?g in fish fed on the control diet or fed the diet devoid of fish meal, respectively. Intestinal morphology did not reveal any histological abnormalities in all dietary groups. Blood parameters including haematocrit and haemoglobin as well as glucose, triglycerides and total protein in the plasma were not different between treatment groups. Thus, the rapeseed protein concentrate tested here has great potential as an alternative to fish meal in rainbow trout diets.     

Utilization of Soluble Canola Protein Concentrate as an Attractant Enhances Production Performance of Sunshine Bass Fed Reduced Fish Meal,Plant‐Based Diets

Soluble canola protein concentrate (SCPC) is rich in glutamic acid and may act as a feed attractant to improve feed acceptance and production performance of fish fed plant‐based diets. In the first experiment, attractant properties of SCPC were evaluated by comparing production performance of sunshine bass, Morone chrysops × Morone saxatilis, fed reduced fish meal (FM) diets supplemented with 1% SCPC or a betaine‐based feed attractant. In the second experiment, production performance of fish was compared after feeding reduced FM diets with or without SCPC. Following the first experiment, production performance was similar among fish fed attractants, but at 0% FM weight gain and survival were significantly lower compared to the 30% FM control treatment regardless of attractant inclusion. According to broken‐line analysis of data from the second experiment, the critical breakpoints in dietary FM inclusion rates needed to achieve maximal weight gain were similar regardless of SCPC. However, weight gain observed among fish fed SCPC was significantly greater than fish not fed SCPC. Including FM in plant‐based sunshine bass diets at rates >10–13% dry matter did not improve weight gain, and weight gain is optimized when a feed attractant/palatant such as SCPC is included in these plant‐based diets.     

Evaluation of fermented soybean meal in the practical diets for juvenile Chinese sucker,Myxocyprinus asiaticus

The study was designed to investigate the influence of fermented soybean meal (FSBM) on the growth and feed utilization of juvenile Chinese sucker, Myxocyprinus asiaticus. Seven isonitrogenous and isolipidic diets were formulated with 0%, 15%, 25%, 35%, 45%, 55% or 65% replacement of fish meal with FSBM on a protein basis. Each diet was fed to three replicate groups of fish with an initial weight 4.59 ± 0.2 g for 8 weeks. Weight gain (WG) and specific growth rate (SGR) was significantly lower when FSBM inclusion was 391 g kg^?1 or greater, replacing more than 45% fish meal protein. A significant negative relationship was observed between growth response and the level of fish meal protein replacement with FSBM. Methionine and Lysine content decreased as FSBM inclusion levels increased, consequently compromising growth performance. Feed intake (FI) were unaffected by dietary FSBM levels. The feed conversion ratio (FCR) of fish fed D‐0, D‐15, D‐25 and D‐35 diets was significantly lower than those fed other diets. The protein efficiency ratio (PER) was highest at the lowest FSBM inclusion level. Experimental diets D‐0, D‐15, D‐25 and D‐35 had apparent dry matter digestibility ranging from 71.2% to 72.6% and apparent protein digestibility (ADPs) from 89.1% to 90.1%, while the diets with higher FSBM inclusion (D‐45 to D‐65) had a significantly lower apparent dry matter digestibility range (69.7–70.3%) and ADPs range (88.5–88.9%). It is concluded that FSBM is an acceptable alternative plant protein source that can replace up to 35% of fish meal protein in diets without significant adverse effects on growth, survival, FCR, PER and body composition.     

Effect of using okara meal,a by‐product from soymilk production as a dietary protein source for Nile tilapia (Oreochromis niloticus L.) mono‐sex males

The main objectives of this study was to evaluate the effect of partial and total replacement of fishmeal protein by okara meal (OM) protein in practical diets on growth performance, feed utilization and body composition of Nile tilapia (Oreochromis niloticus L.) mono‐sex males. Fish of an average initial weight of 2.67 ± 0.01 g were stocked in 15 glass aquariums (80 L each) at a rate of 15 fish per aquarium. Fishmeal protein (18% of the diet) was used as the sole source of animal protein in the control diet. Percent replacement of fish meal (FM) by OM on the basis of crude protein was as follows: 0% (control diet A), 25% (diet B), 50% (diet C), 75% (diet D) and 100% (diet E). Diets were fed to fish at a rate of 5%, and then gradually reduced to 4% of the total fish biomass daily, for a period of 12 weeks. The results revealed that the fish fed diets A (100% FM control), B (25% OM), C (50% OM) and D (75% OM) had significantly the best average body weight, weight gain g, specific growth rate (SGR % day^?1), weight gain % and feed intake g fish^?1 compared with diet E (100% OM) which had the lowest values. There were no significant differences (P > 0.05) among all experimental diets and control in terms of feed conversion ratio (FCR), protein efficiency ratio (PER) and survival rate %. Whole body protein contents for fish fed diets B, C and D were superior to the control diet. Incorporation of OM in the diets increased significantly whole body fat content. Incorporation of OM in the diets significantly increased apparent digestibility coefficient of crude protein crude fat and energy. Therefore, these findings suggest that up to 75% of FM protein can be replaced by OM protein in Nile tilapia, mono‐sex male diets.     

Growth performance,feed utilization and body composition of advanced nursing Nile tilapia (Oreochromis niloticus) fed diets containing Black Soldier Fly (Hermetia illucens) larvae meal

A 32‐day experiment was conducted to evaluate the effects on the performance, feed utilization efficiency and body composition of a strategic inclusion of Black Soldier Fly larvae meal (MM) in a commercially formulated diet for advance nursing Nile tilapia (Oreochromis niloticus). Four isonitrogenous and isoenergetic diets were commercially formulated and manufactured as a control and three test diets with strategic inclusions of MM inclusions (0, 30, 50 and 80 g/kg) and poultry by‐product meal substituting gradually three conventional expensive feedstuffs: fish meal, fish oil and soybean meal. Fish (5.7 ± 0.5 g/fish) were nursed in a cage‐in‐lake system (Volta Lake, Ghana), under conditions similar to commercial farming practices. Control and experimental diets were fed to triplicate cages by hand to visual satiety, six times per day. Growth performance (final weight; weight gain and SGR), feed utilization efficiency indices (FCR and PER) and feed intake were not significantly different (p ≥ .05) between treatments. Survival was significantly different (p < .05) but more likely explained by the stress related to frequent handling on the smaller fish. Fish whole body composition (dry matter, crude protein, lipid, ash and fibre) was unaffected by the treatment (p ≥ .05), except for the fatty acid compositions which mirrored that of the diets.     

Evaluation of Cluster Bean Meal Cyamposis fefrugonoloba as a Dietary Protein Source for Common Carp Cyprinus carpio L.

Abstract— A12-wk feeding experiment was conducted to study the feasibility of utilizing cluster bean seed meal (CBM) as a replacement for fishmeal in the diets for common carp Cyprnus carpio fingerlings. The replacement levels of cluster bean meal protein in the diets were 25, 50, 75, and 100% of the total fishmeal protein. All diets were isonitrogenous at 33.1% crude protein and isocaloric at 4.8 Kcal/g. There were significant differences in the final individual weights, weight gains, specific growth rates (SGR %/d), feed conversion ratios (FCR), feed efficiency ratio (FER), protein efficiency ratios (PER), and feed intake among fish group ( P × 0.05). Common carp fed the diet containing 50% (CBM) exhibited comparable growth to those fed a fishmeal-based diet. Digestibility of protein, energy and lipid decreased with increasing levels of CBM above 50% of total fishmeal replacement in the diet. Incorporation of CBM in diets significantly affected the dry matter, protein, and energy of whole fish body. These results suggest that CBM can replace 50% of the fishmeal in diet for common carp.