The effect of fish meal (FM) substitution with fermented soybean meal (FSBM) in the diets of the carnivorous marine fish, black sea bream, Acanthopagrus schlegelii, was investigated. An 8-wk feeding trial was conducted with black sea bream (11.82 ± 0.32 g; mean initial weight) in indoor flowthrough fiberglass tanks (25 fish per tank). Six isonitrogenous and isoenergetic diets were formulated, in which FM was replaced by FSBM at 0% (control diet), 10% (FSBM10), 20% (FSBM20), 30% (FSBM30), 40% (FSBM40), or 50% (FSBM50), respectively. Each diet was fed to triplicate groups of fish twice daily to apparent satiation. The results showed that there was no difference in survival of black sea bream during the feeding trial. Fish fed the FSBM10 or FSBM20 diet showed comparable growth performance compared with fish fed the control diet (P > 0.05), whereas more than 30% replacement of FM adversely affected weight gain and specific growth rate (P < 0.05). Feed intake was significantly lower for fish fed the FSBM50 diet compared with fish fed the control diet. Feed conversion ratio (FCR) tended to increase with increasing dietary FSBM with the poorest FCR observed for fish fed the FSBM50 diet. Protein efficiency ratio and protein productive values showed similar patterns. Apparent digestibility of nutrients significantly decreased with increasing dietary FSBM level. With the exception of protein content, no significant differences in whole body and dorsal muscle composition were observed in fish fed the various diets. Fish fed the FSBM50 diet had significantly lower intraperitoneal ratio than fish fed the control or FSBM10 diet. Hepatosomatic index and condition factor were unaffected by dietary treatments. This study showed that up to 20% of dietary FM protein could be replaced by FSBM protein in the diets of juvenile black sea bream.

An 8-week feeding trial was conducted to determine the dietary arginine requirement of juvenile black sea bream Sparus macrocephalus in 18 350 L indoors £ow-through circular ¢breglass tanks. Six isonitrogenous and isoenergetic diets were formulated to contain graded levels of L-arginine (1.85%, 2.23%, 2.51%, 2.86%,3.20% and 3.46% dry diet) from dietary ingredients and crystalline arginine. Each diet was randomly assigned to triplicate groups of 25 juvenile ¢sh (10.51 AE 0.15 g) twice daily (08:00 and 16:00 hours) to apparent satiation. Results showed that the speci¢c growth rate (SGR) increased with increasing dietary arginine levels up to 2.51% and remained nearly the same thereafter. Feed e⁄ciency ratio, protein e⁄ciency ratio (PER) and protein productive value all showed an increasing tendency and then levelled o¡. Apparent digestibility coe⁄cients of dry matter, crude protein and gross energy signi¢cantly improved up to 2.86% arginine diet and decreased at di¡erent extents thereafter. Fish fed 1.85% arginine diet had signi¢cantly lower protein content in the whole body and dorsal muscle than those fed diets supplemented with or 42.86% of arginine. Lipid content decreased and lower value occurred at 3.46% of dietary arginine. The dietary essential amino acid composition in the whole body of the black sea bream was signi¢cantly in£uenced by dietary arginine. Arginine retention increased with an increasing dietary arginine level from 1.85% to 3.20%, then declined slightly at 3.46% arginine diet. Serum biochemical parameters were signi¢cantly a¡ected by the dietary arginine level except for the cholesterol content. Broken-line regression based on SGR and second-order polynomial regression based on PER indicated that the optimum dietary arginine requirements for juvenile black sea bream were 2.79% and 3.09% diet, corresponding to 7.74% and 8.13% of the dietary protein respectively. , 320 and p-aminobenzoic acid, 50. zOthers (%) : carboxymethylcellulose, 4; sodium dihydrogen phosphate, 2.5; k-carrageenan, 2.5; a-cellulose, 5.08; betaine, 0.3; Cr 2 O 3 , 0.5. ‰Values for the proximate analysis of the test diets are means of triplicate analyses. Optimum arginine requirement of black sea bream F Zhou et al. Optimum arginine requirement of black sea bream F Zhou et al. r 2010 The Authors Aquaculture Research r 2010 Blackwell Publishing Ltd, Aquaculture Research, 41, e418^e430 e421 Ã Values are presented as mean AE SD (n 5 3); values with di¡erent superscripts in the same row di¡er signi¢cantly (Po0.05).Survival (%) 5 100 Â ¢nal ¢sh number/initial ¢sh number; WG (weight gain) (%) 5 100 Â (FBWIBW)/IBW; SGR (speci¢c growth rate) (% day À 1 ) 5 100 Â (ln FBWln IBW)/day; CF (condition factor) (g cm À 3 ) 5 100 Â (live weight, g)/(body length, cm) 3 ; HSI (Hepatosomatic index) 5 100 Â (liver weight, g)/(body weight, g); FER (feed e⁄ciency ratio) 5 100 Â wet weight gain in g/dry diet fed in g; PER (protein e⁄ciency ratio) 5 weight gain in g/protein intake in dry basis in g; PPV (protein productive value) 5 g protein gain/g pr...

An 8-week feeding trial was conducted to determine the effects of dietary methionine level on juvenile black sea bream Sparus macrocephalus. Fish (initial body weight: 14.21 ± 0.24 g) were reared in eighteen 350-L indoors flow-through circular fibreglass tanks (20 fish per tank). Isoenergetic and isonitrogenous diets contained six levels of L-methionine ranging from 7.5 to 23.5 g kg )1 of dry diet in 3.0 g kg )1 increments at a constant dietary cystine level of 3.1 g kg )1 . Growth performance and feed utilization were significantly influenced by dietary methionine levels (P < 0.05). Maximum weight gain (WG), specific growth rate (SGR), feed efficiency ratio, protein efficiency ratio and protein productive value (PPV) occurred at 17.2 g methionine kg )1 diet, beyond which they showed declining tendency. Protein contents in whole fish body and dorsal muscle were positively correlated with dietary methionine level, while muscle lipid content was negatively correlated with it. Apparent digestibility coefficients (ADCs) of dietary nutrients were significantly affected by dietary treatments except for ADCs of crude lipid. Fish fed the grade level of methionine demonstrated a significant improvement in wholebody methionine content, total essential amino acids ( P EAA), total non-essential amino acids ( P NEAAs) and P EAA/ P NEAA ratio (P < 0.05). Regarding serum characteristics, significant differences were observed in total cholesterol, glucose and free methionine concentration (P > 0.05), while total protein level and triacylglycerol concentration kept relatively constant among treatments (P < 0.05). Analysis of dose response with second-order polynomial regression on the basis of either SGR or PPV, the optimum dietary methionine requirements of juvenile black sea bream were estimated to be 17.1 g kg )1 of diet (45.0 g kg )1 methionine of protein) and 17.2 g kg )1 of diet (45.3 g kg )1 methionine of protein) in the presence of 3.1 g kg )1 cystine, respectively. KEY WORDS

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