The Open Access Israeli Journal of Aquaculture Bamidgeh

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1 The Open Access Isreli Journl of Aquculture Bmidgeh As from Jnury 2010 The Isreli Journl of Aquculture - Bmidgeh (IJA) hs been published exclusively s n online Open Access scientific journl, ccessible by ll. Plese visit our IJA Website for free publictions nd to enble you to submit your mnuscripts. This trnsformtion from subscription printed version to n online Open Access journl ims t supporting the concept tht scientific peer-reviewed publictions nd thus the IJA publictions should be mde vilble to ll for free. Editor-in-Chief Dn Mires Editoril Bord Rin Chkrbrti Angelo Colorni Dniel Golni University of Delhi Indi Ntionl Center for Mriculture Isrel The Hebrew University of Jeruslem Isrel Published by the The Society of Isreli Aquculture nd Mrine Biotechnology (SIAMB) in prtnership with the University of Hwii t Mno Librry nd the AqucultureHub A non-profit orgniztion 501c3 Sheenn Hrpz Dvid Hymer Gideon Hult Ingrid Luptsch Constntinos Mylons Jp vn Rijn Amos Tndler Emilio Tibldi Zvi Yron Agriculturl Reserch Orgniztion, Isrel University of Hwii t Mno USA Agriculturl Reserch Orgniztion, Isrel AB Agri Ltd, UK Hellenic Centre for Mrine Reserch, Greece The Hebrew University of Jeruslem, Isrel Ntionl Center for Mriculture, Isrel Udine University Itly Tel Aviv University Isrel ISSN X Isreli Journl of Aquculture - BAMIGDEH. PUBLISHER: The Society of Isreli Aquculture nd Mrine Biotechnology (SIAMB) Copy Editor Mirim Klein Sofer

2 The Isreli Journl of Aquculture - Bmidgeh, IJA_ , 13 pges Published s n open-ccess journl by the Society of Isreli Aquculture & Mrine Biotechnology (SIAMB). To red ppers free of chrge, plese register online t The sle of IJA ppers is strictly forbidden Efficiency of Dietry β-glucn Supplementtion on Growth, Body Composition, Feed, nd Nutrient Utiliztion in Juveniles of Pompno Fish (Trchinotus ovtus, Linneus, 1758) Do Huu Hong 1,2 *, Ho Son Lm 1, Co Vn Nguyen 1 1 Vietnm Acdemy of Science nd Technology, Institute of Ocenogrphy, 01 Cu D, Nh Trng, Vietnm. 2 Vietnm Acdemy of Science nd Technology, Grdute University of Science nd Technology, 18 Hong Quoc Viet, Cu Giy, H Noi, Vietnm. Keywords: pompno fish; β-glucn; Trchinotus ovtus; growth; feed utiliztion Abstrct An 8-week experiment ws conducted to exmine the effect of incresing levels of dietry β-glucn on the growth performnce, feed utiliztion, nd body composition of juvenile pompno (Trchinotus ovtus). Pompno (men initil weight, 6.45 g) were fed five diets contining five levels of β-glucn (D1 (control): 0%; D2: 0.05%; D3: 0.10%; D4: 0.20%; nd D5: 0.40%. Results showed tht growth performnce, body composition, efficcy of feed nd nutrient utiliztion were significntly ffected by dietry β-glucn levels. After 8-weeks of feeding, weight gin, dily weight gin, specific growth rte, finl body weight, coefficient of vrition were highest in pompno fed 0.05% nd 0.10% β-glucn in the diet (P 0.034), while growth of fish fed 0.2% nd 0.4% β-glucn did not significntly differ compred to fish fed the control diet (P 0.170). Survivl rte of juvenile pompno ws not influenced by β- glucn supplement in the diet (P 0.383). In ddition, feed utiliztion dily feed intke, feed conversion rtio, nd feed conversion efficiency were significntly lower in fish fed diets supplemented with % β-glucn (P 0.027). In contrst, feeds supplemented with 0.2 to 0.4% β-glucn did not influence the feed utiliztion of pompno fter 56 dys of diet feeding (P 0.051). Protein ws significntly higher in the flesh of pompno fed 0.05% to 0.10% β-glucn (P 0.001), while lipid content in fish decresed significntly with grded levels of β-glucn in the diet (P 0.044). After 56 dys, protein efficiency rtio (PER), protein productive vlue (PPV), nd frctionl rtes of protein growth (Kg), were significntly higher in fish fed diets supplemented with % β-glucn (P 0.025). * Corresponding uthor: Do Huu Hong: dohuuhong2002@yhoo.com

3 2 Do-Huu et l Introduction Pompno Trchinotus ovtus (Crngide fmily) is crnivorous fish found in Chin, Jpn, Austrli, Vietnm, nd other countries (Liu nd Chen, 2009). Pompno is highly vlued quculture species with rpid growth rte, high qulity flesh, nd tsty flesh. In recent yers culture of this species hs developed rpidly in Asi nd it hs become one of the most common mrine species in Vietnm, nd is in high demnd (Wng et l., 2013; Zhng et l., 2014). Study of vrious nutrient requirements for golden pompno is necessry to sve feed costs nd improve frming efficiency. The recorded optimum protein requirements of golden pompno rnge from 43%-49% (Liu et l., 2011b), lipid between 6%-6.5% (Wng et l., 2014), nd crbohydrte from 11.2%- 16.8% (Zhou et l., 2015). The optiml requirements of methionine (Lin et l., 2015) nd lysine (Niu et l., 2013) for golden pompno hve lso been determined. In quculture, ntibiotics hve been used s growth promoters for mny yers (Hernández, 2005), however these re hrmful to qutic species, the environment, nd humn helth. Use of ntibiotics ws bnned in quculture (FAO, 2002; Hernández, 2005), therefore more reserch is needed to find ntibiotic replcement (Song et l., 2014). Reserch reveled tht glucn-specific receptors re present on phgocytic cell membrnes of severl species (Brown nd Gordon, 2001). β-glucn dministrtion ws reported to improve immunologicl responses, disese resistnce, intestinl microbiot in invertebrtes (Klenhmmer et l., 2012; Kokoshis et l., 1978). Also, in quculture, β- glucn ppliction ws reported to boost growth performnce in mny species including lrge yellow croker (Pseudoscien croce) (Ai et l., 2007), Atlntic slmon (Slmo slr) (Refstie et l., 2010), koi crp (Cyprinus crpio koi) (Lin et l., 2011) nd rohu (Lbeo rohit) (Misr et l., 2006). However, other studies did not show positive effects on growth performnce, e.g. Europen se bss (Dicentrrchus lbrx) (Bgni et l., 2005). One previous publiction demonstrted the efficcy of dietry β-glucn on growth performnce of pompno (Do-Huu et l., 2016). To the best of our knowledge, the role of dietry β-glucn supplementtion on feed utiliztion nd nutrient utiliztion of pompno is still not fully understood. Therefore, the im of the present study is to exmine the efficcy of dietry β-glucn supplementtion on growth performnce, chnges in body composition, nd nutrition efficiency of pompno T. ovtus. Mteril nd methods Diet ingredients nd preprtion The sme diet formultion ws lso used in previous study on the effects of β-glucn supplementtion on pompno (Do-Huu et l., 2016). The control diet (D1) nd its composition is given in Tble 1. The control diet ws supplemented with 0.05%, 0.10%, 0.20% nd 0.40% of Mcrogrd (Biorigin, Brzil) to mke four supplementl diets, D2, D3, D4 nd D5, respectively. Corn strch ws used to replce Mcrogrd in the control diet (D1). Only the proportion of corn strch ws chnged in proportion to the Mcrogrd supplement. were cold extruded into 2 mm pellets, ir-dried, nd then stored in plstic bgs t -4 C until use. Tble 1. Composition of the bsl diet with crude protein 47.5%, crude lipid 6.4%. Ingredients Percentge Fish mel (62% - Vietnm) Gluten (whet) Soyben Fish oil 4.10 Binder 1.10 Minerl premix 1.50 Vitmin premix 1.50 Corn strch TOTAL 100

4 Dietry β-glucn & feed utiliztion of pompno fish 3 Experimentl fish Pompno juveniles, Trchinotus ovtus (6.45 g ± 0.25, men weight ± SD) were obtined from locl htchery. Fish were kept in 2 m 3 tnk nd cclimted for 3 weeks prior to the experiment during which they were fed commercil diet. The tril ws conducted in the indoor fcilities of the Institute of Ocenogrphy, Nh Trng. A totl of 30 culture tnks (300 L, sized cm) were equipped with n independent recircultion system with flow rte of ~500 L per hour. Wter qulity (NH4/NH3, NO2, slinity nd ph) were mesured every 3 dys. Temperture ws mesured dily. Fish were kept under nturl photoperiod condition throughout the experiment. Experimentl lyout Following cclimtion, twenty-four fish were rndomly stocked in ech of the experimentl tnks with six replictes for ech tretment. To minimize stress, twelve fish were stocked in ech tnk fort the first round nd then the rest were dded to fill the tnks up to 24 fish per tnk. The experiment lsting 56 dys ws designed to compre growth performnce, feed, nd nutrition utiliztion, of pompno fed on the experimentl diets supplemented with four concentrtions of β-glucn. The vrious diets were rndomly llocted to the tnks. Ech tnk served s one experimentl unit to clculte growth, nd feed utiliztion. During the experimentl period, feeds were weighed nd recorded dily for ech tnk. The fish were hnd-fed dily rtion 3% body weight, which ws then visully djusted to pprent stition three times dy (7:30, 12:00, nd 17:30 h). Twenty minutes fter feeding, the uneten feed ws siphoned out, dried, nd weighed to determine net feed consumption. Fish were weighed t 2-week intervls. Body composition ws smpled nd nlyzed t dys 0 nd 56 (end). Nutrient content of ech diet ws lso nlyzed. Smpling nd dt collection During the feeding tril, ll fish were individully weighed on dy 0, nd gin every 14 dys therefter. Fish were strved for 24 h prior to weighing nd smpling. The numbers of ded fish were recorded nd removed dily. At dy 56 (end of feeding tril), one fish from ech replicte tnk (6 fish per tretment) ws scrificed nd smple of the muscle ws tken nd stored t -20 C for lter proximte composition nlysis. Proximte nlysis of experimentl diet nd cultured fish Smples of ech feeding diet (n = 6) were collected for nlysis protein nd lipid content. In ddition, the composition of pooled smple of 15 fish prior to the feeding tril ws rndomly collected for initil proximte nlysis of protein nd lipid content. At the end of the experiment (dy 56), twelve fish from ech tretment were rndomly collected nd scrificed for crcss composition nlysis. Crude protein nd crude lipid were mesured following stndrd methods (Bligh nd Dyer, 1959; Brdford, 1976). Dt clcultion Clcultion of Growth performnce Weight gin WG (g), specific growth rte (SGR, % d -1 ) were clculted s the following formule: WG = (Wt Wo) SGR = 100 [Ln (Wt) Ln (Wo)]/dys Where Wo nd Wt were initil body weight nd body weights of fish t time t (g). Survivl rte ws clculted s follows: Survivl rte = 100 (Nt) / No. Where No ws the initil number of fish nd Nt ws the number of fish t time (t) respectively (Do-Huu et l., 2013). Vrition in body weight ws estimted by the coefficient of vrition (CV, %) with the following formul: CV (%) = 100 SD / X. Where SD ws stndrd devition nd X ws the men weight of fish (Vn Hm et l., 2003).

5 4 Do-Huu et l Clcultion of feed utiliztion of pompno fed different levels of β-glucn Feed consumption (FC) ws estimted by subtrcting uneten feed from feed provided on dry-mtter bsis. Dily feed intke (DFI, % BW/d), feed conversion rtio (FCR) nd feed conversion efficiency (FCE) were clculted s follows: DFI (% BW/d) = 100 FC / [(Wt + Wo)/2]/dys; FCR = FC / WG; FCE = WG / FC (Hellnd et l., 1996; Miliou et l., 2005). Finl biomss (g) totl weight fish in ech replicte tnk t dy 56, biomss gin (g/d): [totl finl weight of fish (g) - totl initil weight (g)]/ dys. Clcultions of nutrition utiliztion of pompno fed different levels of β-glucn Protein efficiency rtio (PER), protein productive vlue (PPV) nd frctionl rtes of protein growth (Kg) were clculted s follows: PER = WG / Pcon., PPV = 100 [(Wt Pt Wo Po] / Pcon (De Silv nd Anderson, 1995; Mundheim et l., 2004). Kg (%/d) = 100 [Ln(Pt) Ln(Po)]/dys (Wootton, 1990). Where Wo nd Wt re initil nd finl body weight, Po nd Pt re initil nd finl fish body protein in fish (%), Pcon.: protein consumption (g), WG: weight gin (g), Pt nd Po re protein content in fish t finl nd initil tril. Sttisticl nlysis Dt re presented s tretment mens ± stndrd error of the men (SEM). The tnk served s the experimentl unit for ech vrible mesured on growth nd feed utiliztion. Dt were nlyzed by one-wy Anlysis of Vrince (ANOVA) to test the effects of the experimentl diets. Before nlysis, dt were checked for vrince homogeneity by using the Kolmogorov Smirnov nd Levene tests, nd dt were trnsformed if necessry. When significnt differences were found (P < 0.05), the lest significnt difference (LSD) post hoc test ws pplied. The reltionships between β- glucn concentrtions in the diets, growth performnce, feed nd nutrition utiliztions were tested by Person correltion (r). All sttisticl nlyses were performed in SPSS 18 (IBM, Chicgo, IL). Results Wter qulity in different tretments Wter qulity in ll experimentl tnks during the experiment is summrized in Tble 2. There were no significnt differences between ll these prmeters mesured during the experiment period (P 0.142). Tble 2. Wter qulity prmeters in different tretments. Dt re presented s men ± SEM. Temperture ( C) 28.5 ± ± ± ± ± 0.32 NH 4/NH 3 (mg/l) 0.03 ± ± ± ± ± 0.01 NO 2 (mg/l) 0.01 ± ± ± ± ± 0.00 Slinity ( ) ± ± ± ± ± 0.18 ph 8.10 ± ± ± ± ± 0.01 Growth performnce of pompno fed different levels of β-glucn Growth performnce verge finl weight, weight gin, dily weight gin, survivl nd coefficient of vrition re presented in Tble 3. In generl, dietry β-glucn supplementtion significntly ffected growth performnce of pompno (Tble 3). Men finl weight, weight gin (WG) nd dily weight gins (DWG) were significntly higher in pompno fed diets supplemented with 0.05% nd 0.10% β-glucn compred to WG nd DWG of fish fed the control diet (P 0.034). However, WG nd DWG of fish fed the diet supplemented with 0.20% nd 0.40% β-glucn did not differ significntly compred to those vlues in fish fed the control diet (P 0.326).

6 Dietry β-glucn & feed utiliztion of pompno fish 5 Tble 3. Growth performnce of pompno fed different levels of β-glucn in the diet (n = 6). Dt re presented s men ± SEM. Different letters indicte significnt differences between tretments. Initil weight (g) 6.29 ± ± ± ± ± 0.56 Finl weight (g) ± ± 5.23 bc ± 3.18 c ± ± 6.44 b WG (g) ± ± 2.20 bc ± 2.60 c ± ± 2.48 b DWG (g/d) 0.57 ± ± 0.04 bc 0.78 ± 0.05 c 0.64 ± ± 0.04 b SGR (%/d) 3.15 ± ± 0.09 bc 3.62 ± 0.08 c 3.30 ± ± 0.09 b Survivl rte (%) ± ± ± ± ± 1.76 CV w (%) ± ± 2.15 b ± 2.32 b ± ± 2.79 WG (g): Weight gin, DWG (g/d): Dily weight gin, SGR (%/d): Specific growth rte, CVw (%): Coefficient of vrition. In the four groups of fish fed β-glucn supplemented diets with, (D2, D3, D4 nd D5), WG nd DWG of fish fed diet D4 did not significntly differ from those vlues in fish fed D2, D3 nd D5 (P 0.089), while WG nd DWG in fish fed the diet with 0.40% β-glucn (D5) ws significntly lower compred to fish fed the diet D3 (P = 0.028); however, no significnt differences were observed between WG nd DWG in fish fed D5, D4, nd D2 (P 0.079). Survivl rte of pompno mong diet tretments rnged from %. However, there ws no significnt difference in the survivl rte of pompno fed different diets (P 0.383). Coefficient of vrition (CV,%) ws highest in the control diet fish (31.19%) nd lowest in fish fed diets D3 nd D2, with CV vlues of 12.75% nd 16.36%, respectively. CV vlues in D2 nd D3 fish were significntly lower thn CV in D1 fish (P 0.002), lso CV in fish fed D2 nd D3 significntly differed from CV in fish fed D4 nd D5 (P 0.045). However, no significnt differences (P 0.170) were observed between CV of fish fed diets D1, D4 nd D5 (see Tble 3). 60 D1 Men Weight (g) D2 D3 D4 D5 0 Wk-0 Wk-2 Wk-4 Wk-6 Wk-8 Time Fig.1. Growth of pompno fed diets with different levels of β-glucn supplementtion. Fortnightly men weight of experimentl pompno is presented in Figure 1. There ws no significnt difference (P 0.452) in men weight of fish between diet tretments t the beginning of the tril. However, weight vrition between diet tretment groups incresed from dy 14 nd ws highest t the end (dy 52) of the tril (Figure 1). At dy 14, men weight of fish fed D2 (0.05% BG), D3 (0.10% BG) nd D4 (0.20% BG) were significntly higher thn weight of fish fed the bsl D1 or diet D5 (0.4% BG)

7 6 Do-Huu et l (P 0.046). However, there were no significnt differences between men weight of fish fed diets D2, D3 nd D4 (P 0.096). At the end of the experiment (Dy 56), weight of fish fed diets D2 nd D3 ws significntly higher compred to weight of fish fed control diets, (P 0.041), but weight of fish fed diets D4 nd D5 did not significntly differ (P 0.337) from tht of fish fed the bsl diet (Fig. 1). Tble 4: Feed utiliztion of pompno fed different levels of β-glucn supplemented in the diets (n=6). Dt re presented s men ± SEM. Different letters indicte significnt differences between tretments. FC (g/tnk) ± ± ± ± ± DFI (%BW/d) 9.60 ± ± 0.42 b 8.7 ± 0.37 b 8.64 ± 0.45 b 9.68 ± 0.34 FCR 1.47 ± ± 0.04 b 1.30 ± 0.05 bc 1.38 ± 0.04 bc 1.45 ± 0.05 c FCE 0.69 ± ± 0.03 b 0.77 ± 0.03 bc 0.73 ± 0.02 bc 0.70 ± 0.02 DBG (g/d) 5.87 ± ± 0.58 b 7.65 ± 0.44 b 6.13 ± ± 0.47 b FC: feed consumption (g/tnk), DFI: dily feed intke (% BW/d), FCR: feed conversion rtio, FCE: feed conversion efficiency, DBG: dily biomss gin (g/d). Feed utiliztion of pompno fed different levels of β-glucn supplementtion Feed utiliztion, biomss t dy 56, nd protein nd lipid content in diets, re shown in Tble 4. At the end of the experiment (dy 56), totl feed consumption rnged from g per tnk, with no significnt differences mong diet tretments (P 0.132). In ddition, significnt differences (P 0.026) in feed intke (FI) nd dily feed intke (DFI) were observed when supplemented % β-glucn in the diet of pompno, while FI nd DFI in groups of fish fed diets with 0.20% nd 0.40% β-glucn did not significntly differ from those vlues in fed fish control diet (P 0.053). Also, there ws no significnt difference in FI nd DFI between three groups of fish fed D2, D3 nd D4 (P 0.055). Feed conversion rtio (FCR) nd feed conversion efficiency (FCE) were significntly lower for fish fed diets D2 nd D3, nd highest in fish fed the control diet (D1), diet D4 nd D5. There were significnt differences in FCR nd FCE between fish fed diet D2 nd D3 (P 0.027), but no significnt difference in FCR nd FCE in fish diet D4 nd D5 (P 0.051) in comprison to those vlues in fish fed the control diet (D1). Furthermore, finl biomss, nd dily biomss gin were significntly higher (P 0.031) in pompno fed diets D2 nd D3 compred to fish fed the control diet. However, those prmeters in fish fed diets D4 nd D5 did not significntly differ (P 0.623) from fish fed the control (Tble 4). The verge protein nd lipid content in the diets rnged between % nd %, respectively. Protein nd lipid contents of the diets were not significntly different (P 0.861) between the experimentl diets (Dt not shown). Body composition of pompno fed different levels of β-glucn t dy 56 At dy 0, the verge protein (CP) nd lipid (CL) content of the fish rnged from 15.91%-16.14% CP nd 5.32%-5.48% LP, respectively. At the end of feeding tril (dy 56), protein content in the flesh of pompno mong the tretments rnged from %, while lipid content rnged from 6.10%-6.55%. In generl, dietry β-glucn supplementtion significntly ffected fish body composition.

8 Dietry β-glucn & feed utiliztion of pompno fish 7 Protein, dy 56, % b b b Lipid, dy 56, % b b b b Fig. 3. Body composition (crude protein nd crude lipid) of pompno fed different concentrtions of β-glucn in the diets t dy 56 (n = 12). Dt re presented s men ± SEM. Different letters indicted significnt differences between tretments. Crude protein content incresed significntly with incresing levels of β-glucn supplementtion, nd highest protein content ws in fish fed D2 nd D3, which ws significntly higher compred to protein content in fish fed D1 (P 0.001). There ws decrese in protein content with higher levels of β-glucn (D4: 0.2% β-glucn nd D5: 0.40% β-glucn) in the diet. Results showed tht no significnt difference in protein content of fish body ws observed from D4 or D5 compred to D1 (P 0.056), but protein content in fish fed D4 nd D5 ws significntly lower thn in fish fed D2 nd D3 (P 0.001). Dietry β-glucn significntly reduced lipid content in the muscle of pompno in comprison to those fed D1 (P 0.044), however, lipid content in fish fed ny levels of β-glucn supplementtion did not differ significntly (P 0.659) from ech other. (Fig. 3). Protein efficient rtio (PER) nd frctionl rtes of protein growth (Kg) in pompno fed levels of β-glucn t dy 56 The results of protein efficient rtio (PER), protein productive vlue (PPV), nd frction rte of protein growth (Ks) re presented in Figure 4. In generl, protein efficient rtio (PER), protein productive vlue (PPV), nd frctionl rtes of protein growth (Kg) of pompno ws significntly influenced by the dietry β-glucn supplementtion. PER, dy 56, % b bc c PPV, dy 56, % b b b

9 8 Do-Huu et l Ks,%, dy b b Fig. 4. Protein efficient rtio (PER), protein productive vlue (PPV) nd frctionl rtes of protein growth (Kg) of pompno fed different levels of β-glucn (dy 56). (n = 6). Dt re presented s men ± SEM. Different letters indicted significnt differences between tretments. 0.0 Protein efficient rtio (PER) vlues were significntly higher in fish fed diets supplemented β-glucn t concentrtions of 0.05% (D2) nd 0.10% (D3) compred to PER in fish fed control (D1) (P 0.025). In contrst, there were no significnt differences in PER vlues either between fish fed diets D4, D5 nd D1 (P 0.266) or between fish fed diets D3 nd D4 (P = 0.224). Moreover, t dy 56, protein productive vlue (PPV) ws significntly higher in fish fed D2 nd D3 compred to fish fed control (D1) nd fish fed D5 (P 0.004), but no significnt differences in PPV vlues between either D4, D5 nd D1 (P 0.057) or between D2, D3 nd D4 (P 0.122). In ddition, frctionl rtes of protein growth (Kg) were significntly higher in fish fed D2 nd D3 compred to Kg in fish fed the control diet (D1) (P 0.003). Conversely, Kg did not significntly differ between fish fed D1 (control), D4 nd D5 (P 0.289). (Fig. 4). Reltionships between levels of dietry β-glucn supplementtion nd growth rte (SGR), feed conversion rtio (FCR) nd protein productive vlue (PPV) At dy 56, β-glucn concentrtions in the diet were significntly nd positively correlted (r 0.708, P ) with men weight, weight gin, dily weight gin, specific growth rte, dily weight increse, finl biomss, nd dily biomss gin of pompno (Tble 5). CV showed significnt nd negtive correltion with the concentrtion of β-glucn in the diet (r = , P = 0.015). FB nd DBG ws significntly nd positively correlted with β-glucn concentrtions (r 0.401, P < 0.027). In growth performnce, SGR hd highest correltion with dietry β-glucn concentrtions (r = P = ). Tble 5. Person correltion (r) mtrix mongst dietry β-glucn inclusion levels (%) nd growth rte, feed nd nutrient utiliztion of pompno t dy 56. Weight WG DWG SGR Survivl CV DBG r ** ** ** ** * * Sig FC DFI FCR FCE PER PPV K g r * * * ** ** * Sig * Correltion is significnt t the 0.05 level (2-tiled). ** Correltion is significnt t the 0.01 level (2-tiled). In the feed utiliztion group, FI, DFI, FCR, FCE, were significntly nd negtively correlted with concentrtions of β-glucn in the diet (r , P 0.017), with the highest significnt correltion in the FCR vlue (r = 0.623, P = 0.012). Similrly, in the nutrient utiliztion the PER, PPV, nd Kg were significntly nd positively correlted with levels of β-glucn supplementtion in the diet (r 0.374, P 0.042), the highest correltion being in PPV vlues (r = 0.627, P = ).

10 Dietry β-glucn & feed utiliztion of pompno fish 9 Discussion This study highlighted the importnce of dietry β-glucn requirements to growth, feed utiliztion, nd nutrient utiliztion, of pompno T. ovtus. In ccordnce with previous reserch (Do-Huu et l., 2016), the present study confirmed tht growth of pompno significntly improved when diet ws supplemented with 0.05% nd 0.10% dietry β-glucn. This is in ccordnce with other studies showing tht dietry β-glucn could boost growth performnce in number of quculture species including snkehed fish, Chnn strit (Munir et l., 2016), Atlntic slmon, Slmo slr (Refstie et l., 2010), snpper, koi crp, Cyprinus crpio koi (Lin et l., 2011), lrge yellow croker, Pseudoscien croce (Ai et l., 2007) nd rohu, Lbeo rohit (Misr et l., 2006). In contrst, in other studies β-glucn dministrtion did not show positive effects on growth performnce, e.g. Europen se bss, Dicentrrchus lbrx (Bgni et l., 2005). Possible fctors re the concentrtion of β-glucn dministrtion in the diet, species specific response, nd experimentl conditions (Dlmo nd Bogwld, 2008; Do-Huu et l., 2016) s well s dministrtion time (Do-Huu et l., 2016; Misr et l., 2006). In our study, pompno (6.45 g), fed β-glucn diets, hd mximl growth rte of 3.62%/d, which is higher thn tht of pompno reported by Liu et l. (2011), but lower thn results by Wng et l. (2013). Although ll the bove experiments cited, including our experiment were conducted for 8 weeks, it is difficult to compre s there were differences in fish size, experimentl conditions, nd diets, between the experiments. In this study, pompno grew very rpidly nd the differences between the diets were detected fter 14 dys. Fst improvement in growth rte my be due to the energy benefits obtined through β-glucn dministrtion (Ai et l., 2007), mnipultion of intestinl microbiot (Do-Huu et l., 2016; Ringø et l., 2010), nd production of digestive enzymes by these beneficil bcteri (Wu et l., 2014). However, in this study, energy benefit, gut microbiot, nd digestive enzymes were not exmined. To understnd more bout the correltion between those fctors nd the growth of pompno, further studies should be conducted. β-glucn dministrtion significntly boosted the growth of pompno nd their survivl rtes did not differ significntly between the diet tretments fter 56 dys of feeding. Similr findings were reported in nother study on snkehed fish (Chnn strit) showing tht β-glucn supplementtion did not ffect survivl of this species (Munir et l., 2016). Biochemicl composition such s protein nd lipids is often used s n indictor of fish nutritionl condition nd helth sttus (Jobling, 1983). Body composition of fish plys n importnt role in quculture s it impcts on fish growth, survivl, nd the efficiency of food utiliztion (Breck, 2014). In the present study, dietry β-glucn supplementtion significntly ffected pompno body composition. Our results reveled tht protein content of pompno ws correlted positively with dietry β-glucn, while the lipid content of the fish hd n inverse reltionship with β-glucn concentrtions. Similr results on effects of dietry β-glucn supplementtion on body composition of other fish species hve been reported. Incresed protein content but reduced lipid content ws reported in snkehed fish Chnn strit, fed β-glucn inclusion in the diet (Munir et l., 2016). It ws lso reported tht dietry β-glucn improved protein levels in white fish, Rutilus frisii kutum, while it did not influence the lipid, sh, nd moisture, of this species (Rufchie nd Hoseinifr, 2014). Moreover, significnt differences in crcss protein levels were observed in Nile tilpi fed commercil live bkers yest Scchromyces cerevisie (Abdel-Twwb et l., 2008). Both protein nd lipid content incresed in red se brem Pgrus mjor, fed β-glucn inclusion in the diet (Mohebbi et l., 2012). In contrry to the bove findings, other studies reveled tht β-glucn dministrtion did not influence protein nd lipid content in rinbow trout, Oncorhynchus mykiss (Seley et l., 2008), in turbot, Scophthlmus mximus (Fuchs et l., 2015) nd Nile tilpi (Selim nd Red, 2015).

11 10 Do-Huu et l Coinciding with those results, it ws reported tht dministrtion of other prebiotics filed to show chnges in body composition of lobster, Pnulirus homrus (Do- Huu nd Jones, 2014). Body composition my be influenced by prebiotic supplementtion however response depends on the species (Grisdle-Hellnd et l., 2008). It ws reported tht the excessive dietry energy supplementtion cn result in high lipid deposition of fish body (Pge nd Andrews, 1973). Lipid content significntly incresed in species such s red drum, Scienops ocelltus (Serrno et l., 1992), flounder, Prlichthys olivceus (Lee nd Kim, 2005), lrgemouth bss, Micropterus slmoides (Anne et l., 2005), cunete drum, Nibe miichthioides (Wng et l., 2006) nd blckspot sebrem, Pgellus bogrveo (Figueiredo-Silv et l., 2010) when fed high dietry lipid levels. In the current study, lipid content in pompno reduced with the incresing levels of dietry β-glucn. In contrry to our findings, no significnt difference ws found in body lipid content between pompno fish fed different dietry protein or lipid levels (Wng et l., 2013). Body composition of quculture fish depends on endogenous nd exogenous fctors (Sherer 1994). Protein content is relted to fish size, while lipid content depends on the diet of cultured fish (Sherer, 1994). In ddition, optiml feed utiliztion plys vitl role in quculture s it cn help to sve feed costs or improve benefits for the culturists. In the present study, high feed utiliztion ws significnt throughout the tril for pompno fed diets with β-glucn supplementtion fter 56 dys of diet feeding. Our study reveled tht feed conversion rtio (FCR) ws lowest in fish fed 0.05% β-glucn (FCR = 1.24), while FCR ws highest in fish fed the control diet (FCR = 1.47). In ccordnce with other studies, the present study concurred tht supplementtion of β-glucn in the diet could improve feed conversion rtio (FCR), feed conversion efficiency (FCE), protein efficient rtio (PER), protein productive vlue (PPV), nd frctionl rtes of protein growth (Kg) of pompno. This is in line with findings tht feed efficiency including feed intke (FI) nd feed efficient rtio (FER) of Atlntic slmon, Slmo slr significntly improved with incresing levels of β-glucn in the diet (Refstie et l. 2010). Similrly, lower FCR were observed in snkehed fish, Chnn strit fed β-glucn diet (Munir et l., 2016). Another study lso indicted tht FCR ws significntly lower in Nile tilpi fed dietry β-glucn supplementtion (Selim nd Red, 2015). Moreover, our study found tht protein efficient rtio (PER), protein productive vlue (PPV), nd frctionl rtes of protein growth (Kg) significntly incresed with the incresing levels of β-glucn in the diet of pompno. These results re in greement with previous studies reported in other species. Increse in PER ws observed in snkehed fish (Chnn strit) fed β-glucn diet (Munir et l. 2016). In contrst with the bove studies, dietry β-glucn did not influence protein efficiency rtio (PER) of Nile tilpi (Selim nd Red, 2015). The present study reveled tht dministrtion of dietry β-glucn improved growth performnce, feed efficiency nd protein efficiency together with higher biomss of pompno t the end of the feeding tril. Higher growth rte together with lower FCR nd more protein efficiency in pompno fed the diets supplemented with β-glucn were found. This indictes tht higher benefits could be ttined with supplementtion of β- glucn in the diet of pompno. However, to understnd this completely, experiments in outdoor nd commercil culture conditions should be conducted. From the present findings, it could be suggested tht optimum growth nd nutrient utiliztion cn be chieved by supplementing low concentrtions of β-glucn in the diet of pompno. Higher growth rtes observed, together with lower feed utiliztion, could suggest lowering feeding cost nd environmentl benefits with less wste per unit of production when supplying pproprite levels of β-glucn in the diet of pompno. However, this should be mesured experimentlly. In conclusion, the results of the present study confirmed tht supplementtion of β- glucn in the diet could improve the growth, protein content in flesh, feed conversion rtio, feed conversion efficiency, protein efficient rtio, nd protein productive vlue in pompno, T. ovtus. It is recommended tht supplementtion of g/kg β-glucn in the diet to obtin mximl growth, feed utiliztion nd protein utiliztion of juvenile

12 Dietry β-glucn & feed utiliztion of pompno fish 11 pompno. However, other potentil positive benefits of dietry β-glucn supplementtion including incresed resilience to pthogens should be further investigted. Also, the effects of dietry β-glucn t different life stges beyond those in this study such s lrve, fry, nd broodstock rering under commercil conditions should be exmined experimentlly. Acknowledgments This reserch ws funded by Vietnm Ntionl Foundtion for Science nd Technology Development (NAFOSTED) under grnt number: 106-NN We prticulrly thnks Dr. Fernndo nd Biorigin for providing Mcrogrd. The uthors would like to express specil thnks to Dr. Huynh Minh Sng, Nguyen Thi Thnh Thuy, Nguyen Thi Nguyet Hue, Nguyen Thi Kim Bich for their help. References Abdel-Twwb M., A.M. Abdel-Rhmn nd N.E.M. Ismel, Evlution of commercil live bkers yest, Scchromyces cerevisie s growth nd immunity promoter for Fry Nile tilpi, Oreochromis niloticus (L.) chllenged in situ with Aeromons hydrophil. Aquculture, 280: Ai Q., K. Mi, L. Zhng, B. Tn, W. Zhng, W. Xu nd H. Li, Effects of dietry β-1, 3 glucn on innte immune response of lrge yellow croker, Pseudoscien croce. Fish Shellfish Immunol., 22: Anne B.L., C.S. D. nd T.J. H., Effect of Dietry Lipid Level nd Protein Energy Rtio on Growth nd Body Composition of Lrgemouth Bss Micropterus slmoides. J. World Aqucult. Soc., 36: Bgni M., N. Romno, M.G. Finoi, L. Abelli, G. Scpigliti, P.G. Tiscr, M. Srti nd G. Mrino, Short- nd long-term effects of dietry yest bet-glucn (Mcrogrd) nd lginic cid (Ergosn) preprtion on immune response in se bss (Dicentrrchus lbrx). Fish Shellfish Immunol., 18: Bligh E.G. nd W.J. Dyer, A rpid method of totl lipid extrction nd purifiction. Cn. J. Biochem. Physiol., 37: Brdford M.M., A rpid nd sensitive method for the quntittion of microgrm quntities of protein utilizing the principle of protein-dye binding. Anl. Biochem., 72: Breck J.E., Body composition in fishes: body size mtters. Aquculture, 433: Brown G.D. nd S. Gordon, Immune recognition: A new receptor for β-glucns. Nture, 413: Dlmo R.A. nd J. Bogwld, Bet-glucns s conductors of immune symphonies. Fish Shellfish Immunol., 25: De Silv S.S. nd T.A. Anderson, Fish Nutrition in Aquculture (Chpmn nd Hll, London, 1995). pp319. Do-Huu H. nd C.M. Jones, Effects of dietry mnnn oligoscchride supplementtion on juvenile spiny lobster Pnulirus homrus (Plinuride). Aquculture, 432: Do-Huu H., H.M. Sng nd N.T. Thnh Thuy, Dietry β-glucn improved growth performnce, Vibrio counts, hemtologicl prmeters nd stress resistnce of pompno fish, Trchinotus ovtus Linneus, Fish Shellfish Immunol., 54: Do-Huu H., S. Tbrett, K. Hoffmnn, P. Köppel nd A.C. Brnes, The purine nucleotides gunine, denine nd inosine re dietry requirement for optiml growth of blck tiger prwn, P. monodon. Aquculture, : FAO, Antibiotics residue in quculture products. The Stte of World Fisheries nd Aquculture, (Rome, Itly) Figueiredo-Silv A.C., G. Corrze, P. Borges nd L.M.P. Vlente, Dietry protein/lipid level nd protein source effects on growth, tissue composition nd lipid metbolism of blckspot sebrem (Pgellus bogrveo). Aquc. Nutr., 16:

13 12 Do-Huu et l Fuchs V.I., J. Schmidt, M.J. Slter, J. Zentek, B.H. Buck nd D. Steinhgen, The effect of supplementtion with polyscchrides, nucleotides, cidifiers nd Bcillus strins in fish mel nd soy ben bsed diets on growth performnce in juvenile turbot (Scophthlmus mximus). Aquculture, 437: Grisdle-Hellnd B., S.J. Hellnd nd D.M. Gtlin, The effects of dietry supplementtion with mnnnoligoscchride, fructooligoscchride or glctooligoscchride on the growth nd feed utiliztion of Atlntic slmon (Slmo slr). Aquculture, 283: Hellnd S.J., B. Grisdle-Hellnd nd S. Nerlnd, A simple method for the mesurement of dily feed intke of groups of fish in tnks. Aquculture, 139: Hernández S., P., Responsible use of ntibiotics in quculture FAO Fisheries Technicl Pper. No Rome, FAO p. Jobling M., A short review nd critique of methodology used in fish growth nd nutrition studies. J. Fish Biol., 23: Klenhmmer T.R., M. Kleerebezem, M.V. Kopp nd M. Rescigno, The impct of probiotics nd prebiotics on the immune system. Nt. Rev. Immunol., 12: Kokoshis P., D. Willims, J. Cook nd N. Di Luzio, Incresed resistnce to Stphylococcus ureus infection nd enhncement in serum lysozyme ctivity by glucn. Science, 199: Lee S.-M. nd K.-D. Kim, Effect of vrious levels of lipid exchnged with dextrin t different protein level in diet on growth nd body composition of juvenile flounder Prlichthys olivceus. Aquc. Nutr., 11: Lin H., X. Tn, C. Zhou, J. Niu, D. Xi, Z. Hung, J. Wng nd Y. Wng, Effect of dietry rginine levels on the growth performnce, feed utiliztion, non-specific immune response nd disese resistnce of juvenile golden pompno Trchinotus ovtus. Aquculture, 437: Lin S., Y. Pn, L. Luo nd L. Luo, Effects of dietry β-1,3-glucn, chitosn or rffinose on the growth, innte immunity nd resistnce of koi (Cyprinus crpio koi). Fish Shellfish Immunol., 31: Liu C. nd C. Chen, The biology nd cultured technology of Pompno (Trchinotus ovtus). Shndong Fisheries, 26: Liu X., H. Wng, H. Zhng nd D. Xu, Optimum dietry protein to energy rtio in Juvenile pompno, Trchinotus ovtus. Fish. Sci., 30: (in Chinese with English bstrct). Liu X., Xu D., H. Zhng nd H. Ling, 2011b. Optimum dietry protein requirement for juvenile Trchinotus ovtus. South Chin Fisheries Science, 7: Miliou H., M. Fintikki, T. Kountouris nd G. Verriopoulos, Combined effects of temperture nd body weight on growth nd protein utiliztion of the common octopus, Octopus vulgris. Aquculture, 249: Misr C.K., B.K. Ds, S.C. Mukherjee nd P. Pttnik, Effect of long term dministrtion of dietry β-glucn on immunity, growth nd survivl of Lbeo rohit fingerlings. Aquculture, 255: Mohebbi A., A. Nemtollhi, E.E. Dorcheh nd F.G. Asd, Influence of dietry grlic (Allium stivum) on the ntioxidtive sttus of rinbow trout (Oncorhynchus mykiss). Aquc. Res., 43: Mundheim H., A. Aksnes nd B. Hope, Growth, feed efficiency nd digestibility in slmon (Slmo slr L.) fed different dietry proportions of vegetble protein sources in combintion with two fish mel qulities. Aquculture, 237: Munir M.B., R. Hshim, M.S. Abdul Mnf nd S.A.M. Nor, Dietry Prebiotics nd Probiotics Influence the Growth Performnce, Feed Utilistion, nd Body Indices of Snkehed (Chnn strit) Fingerlings. Tropicl Life Sciences Reserch, 27: Niu J., Q. Du, H.-Z. Lin, Y.-Q. Cheng, Z. Hung, Y. Wng, J. Wng nd Y.-F. Chen, Quntittive dietry methionine requirement of juvenile golden pompno Trchinotus ovtus t constnt dietry cystine level. Aquc. Nutr., 19: Pge J.W. nd J.W. Andrews, Interctions of dietry levels of protein nd energy on chnnel ctfish (Ictlurus puncttus). J. Nutr., 103:

14 Dietry β-glucn & feed utiliztion of pompno fish 13 Refstie S., G. Beverfjord, R.R. Seim nd O. Elvebø, Effects of dietry yest cell wll β-glucns nd MOS on performnce, gut helth, nd slmon lice resistnce in Atlntic slmon (Slmo slr) fed sunflower nd soyben mel. Aquculture, 305: Ringø E., R.E. Olsen, T.Ø. Gifstd, R.A. Dlmo, H. Amlund, G.I. Hemre nd A.M. Bkke, Prebiotics in quculture: review. Aquc. Nutr., 16: Rufchie R. nd S.H. Hoseinifr, Effects of dietry commercil yest glucn on innte immune response, hemtologicl prmeters, intestinl microbiot nd growth performnce of white fish (Rutilus frisii kutum) fry. Crotin Journl of Fisheries, 72: Seley W.M., F.T. Brrows, A. Hng, K.A. Johnsen, K. Overturf, S.E. LPtr nd R.W. Hrdy, Evlution of the bility of brley genotypes contining different mounts of β-glucn to lter growth nd disese resistnce of rinbow trout Oncorhynchus mykiss. Anim. Feed Sci. Technol., 141: Selim K.M. nd R.M. Red, Bet-Glucns nd Mnnn Oligoscchrides Enhnce Growth nd Immunity in Nile Tilpi. N. Am. J. Aquc., 77: Serrno J.A., G.R. Nemtipour nd D.M. Gtlin, Dietry protein requirement of the red drum (Scienops ocelltus) nd reltive use of dietry crbohydrte nd lipid. Aquculture, 101: Sherer K.D., Fctors ffecting the proximte composition of cultured fishes with emphsis on slmonids. Aquculture, 119: Song S.K., B.R. Beck, D. Kim, J. Prk, J. Kim, H.D. Kim nd E. Ringø, Prebiotics s immunostimulnts in quculture: A review. Fish Shellfish Immunol., 40: Vn Hm E.H., M.H.G. Berntssen, A.K. Imslnd, A.C. Prpour, S.E. Wendelr Bong nd S.O. Stefnsson, The influence of temperture nd rtion on growth, feed conversion, body composition nd nutrient retention of juvenile turbot (Scophthlmus mximus). Aquculture, 217: Wng F., H. Hn, Y. Wng nd X. M, Growth, feed utiliztion nd body composition of juvenile golden pompno Trchinotus ovtus fed t different dietry protein nd lipid levels. Aquc. Nutr., 19: Wng L.-N., W.-B. Liu, K.-L. Lu, W.-N. Xu, D.-S. Ci, C.-N. Zhng nd Y. Qin, Effects of dietry crbohydrte/lipid rtios on non-specific immune responses, oxidtive sttus nd liver histology of juvenile yellow ctfish Pelteobgrus fulvidrco. Aquculture, : Wng Y., J.-l. Guo, K. Li nd D.P. Bureu, Effects of dietry protein nd energy levels on growth, feed utiliztion nd body composition of cunete drum (Nibe miichthioides). Aquculture, 252: Wootton R.J., Ecology of Teleost Fishes. Chpmn nd Hll, London - 404pp. Wu Z.-X., Y.-M. Yu, X. Chen, H. Liu, J.-F. Yun, Y. Shi nd X.-X. Chen, Effect of prebiotic konjc mnnnoligoscchride on growth performnces, intestinl microflor, nd digestive enzyme ctivities in yellow ctfish, Pelteobgrus fulvidrco. Fish Physiol. Biochem., 40: Zhng Q., H. Yu, T. Tong, W. Tong, L. Dong, M. Xu nd Z. Wng, Dietry supplementtion of Bcillus subtilis nd fructooligoscchride enhnce the growth, nonspecific immunity of juvenile ovte pompno, Trchinotus ovtus nd its disese resistnce ginst Vibrio vulnificus. Fish Shellfish Immunol., 38: Zhou C., X. Ge, J. Niu, H. Lin, Z. Hung nd X. Tn, Effect of dietry crbohydrte levels on growth performnce, body composition, intestinl nd heptic enzyme ctivities, nd growth hormone gene expression of juvenile golden pompno, Trchinotus ovtus. Aquculture, 437: