Aquaculture Research, 2009, 40, 456^463 doi:10.1111/j.1365-2109.2008.02116.x

Effects of dietary protein and lipid content on growth performance and biological indices of (Pangasius hypophthalmus, Sauvage 1878) fry

Preeda Phumee, Roshada Hashim, Mohammed Aliyu-Paiko & Alexander Chong Shu-Chien Laboratory of Aquafeed and Feeding Management, Aquaculture Research Group, School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia

Correspondence: R Hashim, Laboratory of Aquafeed and Feeding Management, Aquaculture Research Group, School of Biological Sciences, Universiti Sains Malaysia,11800 Penang, Malaysia. E-mail: [email protected]

Abstract growth and feed utilization comparable to those fed 40% protein/12% lipid diet. Dietary protein and lipid e¡ects on growth, body com- position and indices of iridescent Shark Pangasius hy- Keywords: protein, lipid, protein sparing, Panga- pophthalmus (Sauvage 1878) fry were studied using a sius hypophthalmus,growth 4 2 factorial design. Triplicate groups of 10 ¢sh per tank, with initial mean weights of 3.54^3.85g were fed eight isocaloric diets comprising a combination of four protein levels (250, 300, 350 and 400 g kg 1 or Introduction 25%, 30%, 35% and 40%) and two lipid levels (60 and120 g kg 1 or 6% and 12%) respectively.The ¢sh The commercial culture of Pangasius ¢sh species is were hand-fed to satiety twice daily for 8 weeks. Spe- fast gaining importance based on its increasing pro- ci¢c growth rate (SGR) and feed conversion ratio (FCR) duction volume which has exceeded 150 000 Mt showed signi¢cant e¡ects (Po0.05) with variations in (Phuong, Liem & Tuan 2005). In addition, exports of dietary protein and lipid. The highest SGR was ob- Pangasius to the US markets has increased steadily served in ¢sh fed 40% protein/12% lipid diet but this from the year 1999 to over 18000 Mt annually value was not signi¢cantly (P40.05)di¡erentfrom (Phuong et al. 2005). The iridescent Shark Pangasius the ¢sh fed 30% protein/12% lipid diet. The FCR was hypophthalmus is an omnivorous, freshwater ¢sh na- lowest for the 40/12 diet and di¡ered signi¢cantly tive to most South-East Asian countries, including only with the 25/6,25/12 and 30/6 treatments respec- Malaysia. Currently, the expansion of the aquacul- tively. The hepatosomatic index (HSI) was signi¢- ture of this ¢sh locally has been hampered by low cantly a¡ected by the level of protein, but production ¢gures due to, among others, the lack of intraperitoneal fat (IPF) showed signi¢cant variation quality feeds. Trash ¢sh, vegetables and, in particu- due to dietary lipid level. The HSI signi¢cantly lar, chicken viscera form the major supplementary (Po0.05) decreased when dietary protein increased feeds used among farm operators. from 25% to 30% but increased marginally thereafter. It is well established that dietary protein is a major The IPF values increased with increased dietary lipid factor a¡ecting growth performance of ¢sh and also but decreased with increased dietary protein. Body an important source of energy. It has a tremendous protein was positively correlated with dietary protein e¡ect on the cost of feed (Miller, Davis & Phelps content; conversely,body lipid content decreased with 2005) as its cost is far higher than lipids and carbohy- increase in dietary protein. The results of this experi- drates (Lovell 1989; McGoogan & Gatling III 1999). ment indicate the presence of a protein-sparing e¡ect This leads to the strategy of increasing the lipid level of lipid as ¢sh fed 30% protein/12% lipid diet had in the diet to meet the energy requirements of the ¢sh,

r 2008 Universiti Sains Malaysia 456 Journal Compilation r 2008 Blackwell Publishing Ltd Aquaculture Research, 2009, 40, 456^463 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al. so as to optimize the protein for growth, thus making the best dietary protein and lipid combination for it possible to design economical feeds (Millikin 1983; highest growth. Dias, Alvarez, Diez, Arzel, Gorraze, Bautista & Kaushik 1998; Helland & Grisdale-Helland 1998; Cho & Bureau 2001;Takakuwa, Fukada, Hosokawa & Masu- Materials and methods moto 2006). This has basis, as in carnivorous ¢sh like salmons and marine £at¢sh, optimal growth has Experimental diets been attained when about half the food energy is sup- The study was conducted in a 4 2 factorial design, plied from proteins, while in other species such as with each group made in triplicates. Eight experi- tilapia, cyprinids and some ictalurids, excellent mental diets were formulated to contain four dietary growth rate can be attained with lower dietary pro- protein levels (250,300,350 and 400 g kg 1) for each tein levels (Jobling1994). of the two lipid levels of inclusion (60 and120 g kg 1) In feed formulation, optimizing protein and energy respectively. Ingredients used and proximate compo- levels in a diet not only promote growth and mini- sition values of the diets are presented in Table1. mize nitrogenous output but also reduce the cost of meal served as the protein source, while ¢sh feed. When excess protein is present in the diet, oil (also partially contributed by ¢sh meal) and corn some of it would be utilized for energy production oil mixed in the proportion of 3:1were used as the li- (Ruohonen,Vielme & Groove 1999; Jahan,Watanabe, pid sources. Energy was adjusted at the expense of Satoh & Kiron 2002). This is undesirable because it corn starch to bring all diets to the same level (Kim raises the cost of protein relative to energy and also & Lee 2005). Feed ingredients were mixed in a feed results in increased nitrogen excretion. Alternatively, mixer (Tyrone, model TR 202, L.J. Stuart & Company, a shortage of energy supply in feeds also results in re- Sydney,Australia) and made into pellets of 3 mm dia- duced growth and high nitrogen output (Takakuwa meter with a pelleting machine (Model MH 237, Miao et al. 2006). High lipid levels in the diet have been Hsien,Taichung,Taiwan), dried at room temperature used to augment the supply of ¢sh energy because and stored at 20 1Cuntiluse. they have been implicated to interact with dietary protein to e¡ect growth performance (Miller et al. 2005). There are also reports of improvements Fish and experimental conditions in feed conversion ratio (FCR) values and higher nitrogen and phosphorous retention in ¢sh when Iridescent Shark P. hypophthalmus fry were purchased diets of higher lipid levels are fed (Hillestad, Johnsen, from a commercial ¢sh farm in Perak, Malaysia. Austreng & Ausgard 1998; Hemre & Sadnes Before the feeding experiment, ¢sh were acclimatized 1999). Furthermore, higher lipid concentration in to laboratory conditions in a ¢bre-glass tank and fed a feed pellets contributes to its stability in water maintenance diet for 3 weeks.Two hundred and forty (Chaiyapechara, Liu, Barrows, Hardy & Dong 2003). ¢sh (initial mean body weight 3.54^3.85 g) were ran- However, excess lipid in feed is not recommended domly distributed into twenty-four 30 L aquarium because it could lead to decrease in feed con- tanks. Each tank was supplied with tap water, sumption by ¢sh (Ling, Hashim, Kolkovski & Chong continuously aerated and heated to maintain water 2006). temperature at 30 1C in a closed system. Feeding was Protein levels foroptimal growth of P.hypophthalmus carried out to satiation twice daily at 09:00 and17:00 based on feeding rates range from 16g kg 1day 1 hours. Uneaten feed and faecal matter were siphoned (Pathmasothy & Lim 1988) to 25g kg 1day 1 out daily. During the feeding trial, dissolved oxygen (Chuapoehuk & Pothisoong 1985) and more recently, varied between 4.10and 5.50 mg L 1while pH varied using a protein-rich diet, the value was even higher between 6.29 and 6.60. Individual ¢sh in each at 45 g kg 1day 1 (Hung, Suhenda, Slembrouck, tank were weighed at the beginning and end of the Lazard & Moreau 2004). In the latter study, P. hy- experiment but group weighing was done fortnightly pophthalmus fry was also found to be able to utilize diet- to monitor ¢sh growth. On the completion of the ary lipid energy thus e¡ectively reducing the use of trial after 8 weeks, all ¢sh were starved for 24 h, protein as an energy source. Therefore, the aim of this six ¢sh were randomly removed from each tank study is to investigate the interactive e¡ects of dietary for whole body composition while the remaining protein and lipid on growth and body composition four ¢sh were used for the determination of body of P. hypothalmus fry and consequently determine indices.

r 2008 Universiti Sains Malaysia Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 457 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al. Aquaculture Research, 2009, 40, 456^463

Table 1 Ingredients and composition of experimental diets

25 30 35 40 Dietary protein levels (%) Dietary lipid levels (%) 6 12 6 12 6 12 6 12

Ingredients (g kg 1) Fish mealà 348.1 348.1 417.7 417.7 487.4 487.4 557 557 Corn starch 568 449.3 493.9 375.2 419.8 301 345.7 226.9 Fish oil 22.6 60.1 15.1 52.6 7.6 45.1 0.1 37.6 Corn oil 20 32.5 20 32.5 20 32.5 20 32.5 Choline chloride 10 10 10 10 10 10 10 10 Vitamin mixw 20 20 20 20 20 20 20 20 Mineral mixz 20 20 20 20 20 20 20 20 Cellulose 0.3 69.1 12.3 81.0 22.4 93.0 36.2 105 Proximate composition (g kg 1, dry matter basis) Crude protein 262.3 258.4 312.3 316.7 356.4 353.4 425.8 417.3 Crude lipid 69.8 121.3 66.1 112.2 63.2 111.9 56.8 106.9 Fibre 5.4 20.9 8.6 6.5 2.5 2.6 3.2 3.1 NFE‰ 585.1 521.4 524.5 464.6 481.4 426.5 401.9 350.8 Ash 74.7 78 88.5 99.99 96.5 105.6 112.3 121.9 Moisture 116.9 100.6 115 108.1 112.2 104.7 116.4 114.1 GE (MJ kg 1)z 16.02 16.57 15.36 15.86 15.82 15.48 16.57 15.19 P/E ratio (g MJ 1) 16.37 15.59 20.33 19.97 22.53 22.83 25.70 27.47

ÃDanish ¢sh meal. wVitamin mix kg 1 (ROVIMIX 6288; Roche Vitamins, Basel, Switzerland): Vit. A, 50 million IU; Vit. D3,10million IU; Vit. E, 130 g; Vit. B1, 10g; Vit. B2, 25 g; Vit. B6, 16g; Vit. B12, 100 mg; Biotin, 500 mg; Pantothenic acid, 56 g; Folic acid, 8 g; Niacin, 200 g; Anticake, 20 g; antioxidant, 200 mg; Vit. K3, 10g and Vit. C, 35 g. zMineral mix kg 1: Calcium phosphate (monobasic, 397.5 g; calcium lactate, 327 g; ferrous sulphate, 25 g; magnesium sulphate, 137 g; potassium chloride, 50 g; sodium chloride, 60 g; potassium iodide, 150 mg; copper sulphate, 780 mg; manganese oxide, 800 mg; cobalt carbonate 100mg; zinc oxide, 1.5 g and sodium selenite, 20 mg. ‰NFE (nitrogen free extract) 5 10 0 (protein1lipid1ash1¢bre). zGE, gross energy measured in a bomb calorimeter.

Data and statistical analysis Body indices: Hepatosomatic index ðHSI%Þ Growth performance, body composition and index 100 liver weight=body weight were compared using two-way analysis of variance ¼ ð Þ (ANOVA)atP 0.05 level of signi¢cance and if found Intraperitoneal fat ðIPF%Þ to be signi¢cant (Po0.05), Tukey’s test was used to ¼ 100 ðintraperitoneal fat weight= compare the data. All statistical analysis was carried body weightÞ out using the SPSS program, version11.5. Viscerosomatic weight ðVSI%Þ The following parameters were calculated based ¼ 100 ðviscera weight=body weightÞ on the formulae mentioned below. where Wt refers to the mean ¢nal weight, Wi is the Growth parameters: mean initial weight and T is the feeding trial period Specific growth rate ðSGR %Þ in days. The feed ingredients, experimental diets and ¢sh ¼½ðln Wt ln WiÞ=T100 carcass were analysed for their proximate composi- Feed conversion ratio ðFCRÞ tions using standard Association of O⁄cial Analyti- ¼ total feed intake ðgÞ=total wet weight gain ðgÞ cal Chemists methods (1997). Protein efficiency ratio ðPERÞ ¼ wetweightgainðgÞ=total protein intake Total feed intake per fish ðFIÞ Results ¼ total feed intake=number of fish No mortality was recorded during the period of Protein intake ðPIÞ the experiment. Table 2 summarizes the growth per- ¼ feed intake ðgÞper cent protein in the diet formance, feed and protein e⁄ciency as well as the

r 2008 Universiti Sains Malaysia 458 Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 Aquaculture Research, 2009, 40, 456^463 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al.

Table 2 Growth performance and feed utilization (dry matter basis) of iridescent Shark, Pangasius hypophthalmus fry fed experimental diets containing di¡erent protein and lipid levels for 8 weeks

Dietary Dietary Init. FBW SGR protein (%) lipid (%) wt. (g) (g) (%) FCR PER PI FI

25 6 3.85 0.21 8.83 0.79bc 1.53 0.23ab 3.17 0.20bc 1.20 0.07abc 0.75 0.09ab 14.86 2.46 12 3.75 0.22 7.25 0.20a 1.12 0.01a 3.80 0.05c 1.02 0.01a 0.59 0.01a 15.33 4.32 30 6 3.63 0.19 8.69 0.06b 1.51 0.09ab 3.08 0.26bc 1.04 0.09a 0.85 0.04abc 15.85 1.10 12 3.60 0.06 11.36 0.25d 2.06 0.01de 1.94 0.06a 1.63 0.05c 0.85 0.04abc 14.66 0.95 35 6 3.67 0.21 9.42 0.17bc 1.64 0.05bc 2.35 0.08ab 1.19 0.04abc 0.85 0.03abc 13.03 0.57 12 3.76 0.24 10.10 0.08cd 1.75 0.14bcd 2.22 0.47a 1.30 0.27abc 0.89 0.22abc 13.56 2.63 40 6 3.73 0.18 10.87 0.24d 1.96 0.04cde 2.18 0.01a 1.08 0.004ab 1.20 0.05c 15.09 1.37 12 3.54 0.07 12.75 0.29e 2.28 0.08e 1.57 0.17a 1.54 0.17bc 1.08 0.16bc 15.20 2.20 Protein (P) level (g kg 1) 250 3.80 0.2 8.04 1.02a 1.32 0.27a 3.49 0.38c 1.11 0.12 0.67 0.11a 15.10 3.16 300 3.62 0.13 10.02 1.55b 1.79 0.32b 2.51 0.67b 1.33 0.34 0.85 0.03a 15.26 1.13 350 3.71 0.21 9.76 0.41b 1.69 0.11b 2.29 0.28ab 1.25 0.17 0.87 0.13a 13.30 1.73 400 3.63 0.16 11.81 1.11c 2.12 0.19c 1.88 0.37a 1.31 0.28 1.14 0.12b 15.15 1.55 Lipid (L) level (g kg 1) 60 3.72 0.19 9.45 0.98 1.66 0.22 2.70 0.48 1.13 0.09 0.91 0.19 14.71 1.70 120 3.66 0.18 10.37 2.17 1.80 0.47 2.38 0.93 1.37 0.28 0.85 0.21 14.69 2.47 Two-way ANOVA P level NS Po0.01 Po0.01 Po0.01 NS Po0.01 NS L level NS Po0.01 Po0.05 Po0.05 Po0.01 NS NS P LNSPo0.01 Po0.01 Po0.01 Po0.01 NS NS

All values are mean SD, obtained from three replicates. Values in the same column with di¡erent superscript letters are signi¢cantly di¡erent (Po0.05). Init. wt. (g), initial body weight; FBW (g), ¢nal body weight; SGR (%), speci¢c growth rate; FCR, feed conversion ratio; PER, protein e⁄ciency ratio; PI, protein intake; FI, total feed intake per ¢sh; ANOVA, analysis of variance.

protein and daily feed intake of P.hypophthalmus fry ever, an increase in the lipid level from 6% to 12% obtained at the end of the experimental period. across all protein levels tested resulted in an improve- Generally,the ¢nal body weight (FBW) and SGR of ment of PER, except for 25% protein level where the P. h y p o p h t h a l m u s fry improved signi¢cantly (Po0.05) trend was reversed. Generally, DFI consistently de- with the increase in protein levels. There was, how- creased as lipid level in the diet increased from 6% to ever, no signi¢cant (P40.05) di¡erence between the 12%.The results of PI increased as dietary protein le- SGR of ¢sh fed the 30% protein/12% lipid diet and vels elevated, but the e¡ect was only signi¢cant those fed 40% protein/12% lipid, even though the (Po0.05) at 40% protein inclusion.The PI was not af- FBW of the later treatment was signi¢cantly fected by increase in lipid content for all protein le- (Po0.05) higher. As for the lipid levels, an increase vels. Two-way ANOVA results also show that from 6% to 12% resulted in an improvement in FBW interaction between protein and lipids had signi¢- and SGR for all levels of protein tested except at 25% cant (Po0.05 or Po0.01) e¡ects on the feed utiliza- protein where the trend showed a reversal in growth. tion parameters. Growth parameters were highest for the 40% protein The results of the HSI, IPFandVSI, which were the diets regardless of lipid level and were similar to the body indices monitored, are presented in Table 3. 30% protein/12% lipid diets. The two-way ANOVA re- From the results, it was observed that HSI de- sult shows that interaction between proteins and creased signi¢cantly (Po0.05) from the 25% to 30% lipids signi¢cantly (Po0.05 or Po0.01) a¡ected protein level and marginally increased at levels FBWand SGR.With the exception of the 25% protein 430%. Increase in dietary lipid level from 6% to treatment, FCR was signi¢cantly (Po0.05) a¡ected 12% caused an insigni¢cant (P40.05) reduction in and generally improved with increase in lipid and HSI. The IPF showed a signi¢cant (Po0.05) increase when dietary protein increased from 30% to 40%. with more lipid in the diet, but resulted in a nonsigni- In contrast, PER was not signi¢cantly a¡ected ¢cant (P40.05) decrease when dietary protein level (P40.05) by increase in dietary protein levels. How- was raised. The VSI decreased as protein levels

r 2008 Universiti Sains Malaysia Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 459 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al. Aquaculture Research, 2009, 40, 456^463

Table 3 Hepatosomatic index (HSI), intraperitoneal fat Discussion (IPF) and viscerosomatic index (VSI) of iridescent Shark Pangasius hypophthalmus fry fed experimental diets contain- The present study demonstrates the existence of in- ing di¡erent protein and lipid levels for 8 weeks teractions between dietary protein and lipids on the growth of P. hypophthalmus fry. As only a numeri- Dietary Dietary HSI IPF VSI cally higher, but not signi¢cantly di¡erent (P40.05) protein (%) lipid (%) (%) (%) (%) growth was attained with 40% protein, 12% lipid 25 6 2.09 0.12 2.23 0.26 7.37 0.67 and a P/E ratio of 27.47 g MJ 1 dietary combination, 12 1.85 0.16 2.11 1.79 7.35 1.69 the diet containing 30% protein, 12% lipid and for- 30 6 1.70 0.24 1.44 1.07 6.08 1.32 mulated to provide 15.86 MJ kg 1 gross energy (GE) 12 1.70 0.19 3.23 0.75 7.79 0.86 1 35 6 1.81 0.13 1.94 0.75 6.62 0.85 and a P/E ratio of 20.02 g MJ can be deemed as sui- 12 1.72 0.04 1.64 0.82 6.32 0.93 table for optimal growth for P. hypophthalmus fry. 40 6 1.84 0.09 0.57 0.23 5.84 0.40 This result is consistent with the results observed for 12 1.73 0.22 2.58 1.14 6.78 1.05 other ¢sh species such as 30% protein and 12% lipid Protein (P) level (g kg 1) for swordtails Xiphorus helleri (Poeciliidae) (Ling et al. 250 1.97 0.18b 2.17 1.15 7.36 1.15 300 1.70 0.19a 2.34 1.29 6.94 1.37 2006), 40% and 30% protein for smaller and med- 350 1.76 0.10ab 1.79 0.72 6.47 0.81 ium-sized Pangacius sanitwongsei respectively (Una- 400 1.78 0.16ab 1.58 1.32 6.31 0.88 kornsawat, Chutjareyaves & Singsawat 2004) and 1 Lipid (L) level (g kg ) 39% DPand14.2 MJg 1 DE for Seriola dumerili (Riso) 60 1.86 0.20 1.55 0.87a 6.48 0.97 (Takakuwa et al. 2006). The additional protein and 120 1.75 0.15 2.39 1.19b 7.06 1.17 Two-way ANOVA lipid energy was considered excessive as it led to no P level P 5 0.05 NS NS signi¢cant appreciation in weight. Non-bene¢cial ef- L level NS P 5 0.05 NS fects of excessive dietary lipid on growth perfor- P LNSNSNSmance has also been observed in other studies All values are mean SD, obtained from three replications. (Davis & Arnold 1997; Jover, Garcia-Gomez, Tomas, Values in the same column with di¡erent superscript letters are De la Gandara & Perez 1999; Lee, Kim & Lall 2003) signi¢cantly di¡erent (Po0.05). and therefore supports the suggestion that it is only ANOVA, analysis of variance. essential to provide an adequate level and ratio of dietary protein and non-protein energy in order to re- increased, but a reverse trend was observed as diet- duce the catabolism of protein for energy. ary lipid level increased where values increased but Growth rate increased signi¢cantly (Po0.05) with not signi¢cantly (P40.05). increase in lipid from 6% to 12% at all the protein le- Proximate composition of the whole body of P. h y - vels tested, except at 25% inclusion, at which level the pophthalmus fry fed the experimental diets shows protein was considered inadequate. The combination that body moisture content was not in£uenced by of ¢sh oil and corn oil in the proportion used seemed either protein or lipid levels in the diet (Table 4). e⁄cient as the non-protein energy source for P. h y - Dietary protein had e¡ect on body protein content, pophthalmus fry. Indeed, the similar growth rate be- as an improvement was observed with increase in tween ¢sh that received 40% protein/12% lipid and protein in the diet, but not with increase in lipid. The 30% protein/12% lipid, suggests a protein-sparing ef- increase in body protein with increase in dietary pro- fect by the12% lipid inclusion. Protein-sparing e¡ect tein level was, however, only signi¢cant (Po0.01) has been reported in several ¢sh species fed high en- with increase in dietary proteins from 25% to 30%. ergy diets containing lipid as the major non-protein Body lipid level was a¡ected by dietary protein level. energy source (Vergara, Lopez-Calero, Robaina, Even though the e¡ect was not signi¢cant (Po0.01) Caballero, Montero, Lzquierdo & Aksnes 1999; Lee, when protein in the diet was increased from 25% to Jeon & Lee 2002; Skali, Hidalgo, Albellan, Arizcun & 30% and from 35% to 40%, the body lipid level Cardenete 2004; Ling et al. 2006; Wang, Guo, Li & tended to decrease with increase in dietary protein. Bereau 2006). Nonetheless, some ¢sh species have The level of lipid in the diet also a¡ected body lipid also been reported to be ine⁄cient users of lipid as a level. With the exception of the 25% protein that major non-protein energy source, in which case an caused a decrease in body lipid when dietary lipid in- increase in dietary lipid a¡ected growth negatively creased, increments in body lipid were insigni¢cant (Nyina-wamwiza, Xu, Blachard & Kestemont 2005; at protein levels beyond the 35%. Takakuwa et al. 2006).

r 2008 Universiti Sains Malaysia 460 Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 Aquaculture Research, 2009, 40, 456^463 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al.

Table 4 Proximate analysis results of whole body (dry mater basis) of iridescent Shark, Pangasius hypophthalmus fry fed diets containing di¡erent protein and lipid levels

Dietary Dietary Moisture Protein Lipid Ash protein (%) lipid (%) (%) (%) (%) (%)

25 6 23.49 0.34 46.54 0.38 19.26 0.77 17.75 0.82 12 23.12 0.90 47.31 0.47 17.60 0.94 19.12 0.64 30 6 22.63 0.97 50.12 0.73 15.96 0.47 17.96 0.29 12 24.88 0.24 48.38 0.40 20.99 0.78 16.75 0.35 35 6 22.90 0.42 49.37 0.66 15.56 0.78 19.36 0.59 12 22.83 0.79 50.62 0.74 15.58 0.59 18.0 0.78 40 6 23.19 0.90 50.77 0.52 15.29 0.75 17.64 0.66 12 23.57 0.55 49.72 0.79 15.47 0.45 17.77 0.50 Protein (P) level (g kg 1) 250 23.30 0.64 46.93 0.57a 18.43 1.19b 18.43 1.00b 300 23.75 1.38 49.25 1.09b 18.47 2.81b 17.36 0.72a 350 22.87 0.57 50.00 0.93b 15.57 0.62a 18.68 0.97b 400 23.38 0.69 50.24 0.83b 15.38 0.56a 17.71 0.53ab Lipid (L) level (g kg 1) 60 23.05 0.69 49.20 1.76 16.52 1.78 18.18 0.90 120 23.60 1.0 49.01 1.42 17.41 2.41 17.91 1.01 Two-way ANOVA P level NS Po0.01 Po0.01 Po0.01 L level NS NS Po0.01 NS P L Po0.01 Po0.01 Po0.01 Po0.01

All values are mean SD, obtained from three replications. Values in the same column with di¡erent superscript letters are signi¢cantly di¡erent (Po0.05). ANOVA, analysis of variance.

The main storage sites for lipid in the body of ¢sh increased dietary protein on elevating the body pro- are liver, perivisceral adipose tissues or the muscles tein and reducing body lipid contents, as found in this (Corraze 2001).The contradictory e¡ect of increasing study, agree with results reported for rohu, Labeo dietary lipid on HSI and IPF values suggests that rohita (Satpathy,Mukherjee & Ray 2003); silver perch, P. hypophthalmus fry has a tendency to store excess Bidyanus bidyanus (Yang, Liou & Lui 2002); black cat- dietary lipid in the form of fat in the perivisceral adi- ¢sh, Rhamdia quelen (Salhi, Bessonrt, Chediak, Bella- pose tissues rather than the liver. It also appears that gamba & Carnevia 2004); Japanese seabass, lipid deposition in the viscera by the P. h y p o p h t h a l m u s Lateolabrax japonicus (Ai, Mai, Li, Zhang, Duan, Tan, fry, does not distinguish between the carbon sources Xu, Ma, Zhang & Liufu 2004) and bagrid cat¢sh, as Hung et al. (2004) recently reported a similar trend Pseudobagrus fulvidraco (Kim & Lee 2005). Increasing in lipid deposition when high dietary starch diets dietary lipid level also has an e¡ect of increasing the were fed to P. hypophthalmus fry. Similarly, in other fat deposition in the bodyonly up to 30% protein level studies, for instance, the inclusion of dietary lipid of inclusion, beyond which the body lipid remained in excess of the energetic demands for juvenile virtually unchanged but with a concomitant decline red snapper caused a signi¢cant increase in its IPF in the deposition of fat in the perivisceral adipose tis- (Miller et al. 2005). In juvenile rock¢sh, it was re- sue. It is likely that the decline in lipid deposition in ported that a high lipid diet resulted in an increase the viscera when dietary protein level exceeded 30% in the content and viscera lipid deposition (Lee et al. was a result of increased metabolic activitycaused by 2002). However, this trend is not seen for all ¢sh as the increased dietary protein intake, and thus non- studies have also shown that dietary lipid levels have protein energy expense for the catabolism of the ex- no e¡ect on HSI in some marine ¢sh (Schulz, Knaus, cess protein including nitrogenous waste detoxi¢ca- Wirth & Rennert 2005;Wang et al. 2006). tion and elimination. Body protein content is in£uenced by dietary pro- In conclusion, P.hypophthalmus fry grew best on a tein uptake and protein deposition, which positively diet containing 30% protein/12% lipid and formu- correlates with dietary protein levels. The e¡ects of lated to provide 15.86 MJ kg 1 GE and a P/E ratio of

r 2008 Universiti Sains Malaysia Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 461 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al. Aquaculture Research, 2009, 40, 456^463

20.02 g MJ 1. Increasing the protein level to 40% did Hemre G.I. & Sadnes K. (1999) E¡ects of dietary lipid on the not show any signi¢cant (Po0.05) response in muscle composition in Atlantic salmon (Salmo salar). weight gain, but seemed to con¢rm the presence of a Aquaculture Nutrition 5,9^16. protein-sparing e¡ect of the 12% dietary lipid con- Hillestad M., Johnsen F., Austreng E. & Ausgard T. (1998) tent. Whole body protein content is in£uenced by Long term e¡ects of dietary fat level and feeding rate on dietary protein level as did the body lipid content growth, feed utilization and carcass quality of Atlantic salmon. Aquaculture Nutrition 4, 89 ^ 97. with dietary lipid content up to the level that non- Hung L.T., Suhenda N., Slembrouck J., Lazard J. & MoreauY. protein energetic requirements are met. (2004) Comparison of dietary protein and energy utiliza- tion in three Asian cat¢shes (Pangasius bocourti, P. h y - pophthalmus and P. djambal). Aquaculture Nutrition 10, Acknowledgment 317^326. Jahan P., Watanabe T., Satoh S. & Kiron V. (2002) A labora- This research was funded by the USM short-term tory-based assessment of phosphorous and nitrogen load- grant number 304/PBiologi/637056. ing from currently available carp feeds. Fisheries Science 68,579^586. Jobling M. (1994) Fish Bioenergetics. Chapman & Hall, Lon- References don, UK,309pp. Jover M., Garcia-Gomez A.,Tomas A., De la Gandara F.& Perez Ai Q., Mai K., Li H., Zhang L., Duan Q.,Tan B., XuW., Ma H., L. (1999) Growth of Mediterranean yellowtail (Seriola du- ZhangW.& Liufu Z. (2004) E¡ects of dietary protein to en- merilii) fed extruded diets containing di¡erent levels of pro- ergy ratios on growth and body composition of juvenile tein and lipid. Aquaculture179, 25^33. seabass, (Lateolabrax japonicus). Aquaculture 230,507^516. Kim L.O. & Lee S.M. (2005) E¡ects of the dietary protein AOAC (1997) feeds. Chapter 4. In: O⁄cial Methods of and lipid levels on growth and body composition of Ba- Analysis Association of O⁄cial Analytical Chemists Interna- grid cat¢sh (Pseudobagrus fulvidraco). Aquaculture 243, tional (ed. by P.A. Cunniff), 16th edn. Vo l. 1 , pp. 1–3. AOAC, Arlington, VA, USA. 323^329. Chaiyapechara S., Liu K.K.M., Barrows F.T., Hardy R.W. & LeeS.-M.,JeonI.G.&LeeJ.Y.(2002)E¡ectsofdigestiblepro- Dong F.M. (2003) Proximate composition, lipid oxidation tein and lipid levels in practical diets on growth, protein and sensory characteristics of ¢llets from rainbow trout utilization and body composition of juvenile rock¢sh (Se- (Oncorhynchus mykiss) fed diets containing 10% to 30% bastes schlegeli). Aquaculture 211,227^239. lipid. Journal ofWorld Aquaculture Society 34,266^277. Lee S.-M., Kim K.D. & Lall S.P. (2003) Utilization of glucose, Cho C.Y. & Bureau D.P. (2001) A review of diet formulation maltose, dextrin and cellulose by juvenile £ounder (Para- strategies and feeding systems to reduce excretoryand feed lichthys olivaceus). Aquaculture 221, 427^438. wastes in aquaculture. Aquaculture Research 32,349^360. Ling S., Hashim R., Kolkovski S. & Chong A.S.C. (2006) Ef- Chuapoehuk W. & Pothisoong T. (1985) Protein require- fects of varying dietary lipid and protein levels on growth ments of cat¢sh fry, Pangasius sutchi, Fowler. In: Fin¢sh and reproductive performance of female Swordtail (Xi- Nutrition in Asia: Methodological Approaches to Research phorus helleri, Poeciliidae). Aquaculture Research 37, Development (ed. by C.Y. Cho, C.B. Cowey & T.Watanabe), 1267^ 1275. pp.103^106. International Development Research Centre, Lovell R.T. (1989) Nutrition and Feeding of Fish.Van Nostrand- Ottawa, Canada. Reinhold, NewYork, NY, USA, 260pp. Corraze G. (2001)Lipid nutrition. In: Nutrition and Feeding of McGoogan B.B. & Gatling D.M. III (1999) Dietary manipula- Fish and Crustaceans (ed. by J. Guillaume, R. Metailler, tions a¡ecting growth and nitrogenous waste production S. Kaushik & P. Bergot), pp. 111–129. Springer-Praxis of red drum (Sciaenops ocellatus). Aquaculture 178, Publishing, Chichester, UK. 333^348. Davis D.A. & Arnold C.R. (1997) Response of Atlantic croaker Miller C.L., Davis D.A. & Phelps R.P.(2005) E¡ects of dietary ¢ngerlings to practical diet formulations with varying protein and lipid on growth and body composition of ju- protein and energy contents. Journal of theWorld Aquacul- venile and sub-adult red snapper (Lutjanus compechanus, ture Society 28,241^248. Poey 1860). Aquaculture Research 36,52^60. Dias J., Alvarez M.J., Diez A., Arzel J., Gorraze G., Bautista Millikin M.R. (1983) Interactive e¡ects of dietary protein on J.M. & Kaushik S.J. (1998) Regulation of hepatic lipogen- growth and utilization of age-0 striped bass. Transactions esis by dietary protein energy in juvenile European sea- of theAmerican Fisheries Society112, 185^193. bass (Diecentrarchus labrax). Aquaculture161,169^186. Nyina-wamwiza L., Xu X.L., Blachard G. & Kestemont P. Helland S.J. & Grisdale-Helland B. (1998) Growth, feed utiliza- (2005) E¡ect of dietary protein, lipid and carbohydrate tionand bodycompositionof Atlantic halibut (Hippoglossus ratio on growth, feed e⁄ciency and body composition hippoglossus) fed diets di¡ering in the ratio between the of pike perch (Sander lucioperca) ¢ngerlings. Aquaculture macro-nutrients. Aquacuculture124,109^116. Research 36, 486^492.

r 2008 Universiti Sains Malaysia 462 Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 Aquaculture Research, 2009, 40, 456^463 Protein/Lipid in diet on growth of P.hypophthalamus fry P Phumee et al.

Pathmasothy S. & Lim L.T. (1988) The response of Pangasius and nutrient utilization in common dentex (Dentex dentex sutchi (Fowler) ¢ngerlings fedan isocaloric diet withvariable L.) at di¡erent growth stages. Aquaculture 235,1^11. protein levels. Malaysian AgricultureJournal 54,81^90. Takakuwa F., Fukada H., Hosokawa H. & Masumoto T. Phuong N.T., Liem P.T. & Tuan N.A. (2005) An overview of (2006) Optimum digestible protein and energy levels and cat¢sh farming industry in the Mekong river delta of Viet- ratio for greater amberjack (Seriola dumerili, Riso) ¢nger- nam. Proceeding of World Aquaculture Society (Bali, ling. Aquaculture Research 37,1532^1539. meeting Abstract), 9–13 May, 2005. 621pp. Unakornsawat Y., Chutjareyaves S. & Singsawat U. (2004) Ruohonen K.,Vielme J. & Groove D.J. (1999) Low-protein sup- Protein requirement of chao-phya giant cat¢sh, Pangacius plement increases protein retention and reduces the sanitwongsei, Smith 1931. Technical paper No. 87/ amount of nitrogen and phosphorous wasted by rainbow 2004, Phyao Inland Fisheries Research and Deve- trout fed on low-fat herring. Aquaculture Nutrition 5,83^91. lopment Center, Fisheries Department, Thailand, 23pp Salhi M., Bessonrt M., Chediak G., Bellagamba M. & Carnevia (in Thai). D. (2004) Growth, feed utilization and body composition of Vergara J.M., Lopez-calero G., Robaina L., Caballero M.J., black cat¢sh (Rhamdia quelen) fry fed diets containing dif- Montero D., Lzquierdo M.S. & Aksnes A. (1999) Growth, ferent protein and energy levels. Aquaculture 231,435^ feed utilization and body lipid content of gilthead 444. seabream (Sparus aurata) fed increasing lipid levels Satpathy B.B., Mukherjee D. & RayA.K. (2003) E¡ects of diet- and ¢sh meals of di¡erent quality. Aquaculture 179, ary protein and lipid levels on growth, feed conversion 35^44. and bodycomposition of rohu (Labeo rohita, Hamilton) ¢n- WangY., GuoJ-L., Li K. & Bereau D.P.(2006) E¡ects of dietary gerlings. Aquaculture Nutrition 9,17^24. protein and energy levels on growth, feed utilization and Schulz C., Knaus U., Wirth M. & Rennert B. (2005) E¡ects of body composition of cuneate drum (Nibea miichthioides). varying dietary fatty acid pro¢le on growth performance, Aquaculture 252,421^428. fattyacid bodyand tissue composition of juvenile Pike perch Yang S.D., Liou C.H. & Lui F.G. (2002) E¡ects of dietary pro- (Sander lucioperca). Aquaculture Nutrition11,403^413. tein level on growth performance, carcass composition Skali A., Hidalgo M.C., Albellan E., Arizcun M. & Cardenete and ammonia excretion in silver perch (Bidyanus bidya- G. (2004) E¡ects of the dietary protein/lipid on growth nus). Aquaculture 231,363^372.

r 2008 Universiti Sains Malaysia Journal Compilation r 2008 Blackwell Publishing Ltd, Aquaculture Research, 40, 456^463 463