【作者】 王裕玉；

【导师】 刘大森；

【作者基本信息】 东北农业大学 ， 动物营养与饲料科学， 2013， 博士

【摘要】 乌苏里拟鲿(Pseudobagras ussuriensis)是分布在我国黑龙江水系特有的江河野生经济鱼类。多栖息于缓流中,具有肉质细嫩、味道鲜美等特点,具有很高的食用价值和经济价值。迄今对于其营养生理研究报道非常有限,因此,开展乌苏里拟鲿营养需求的研究已成为乌苏里拟鲿养殖业持续健康发展迫切需要解决的问题。本文主要研究2方面的内容：一是对野生及养殖乌苏里拟鲿的肌肉营养成分进行分析,并对其营养品质进行评价；二是采用营养学、能量学和生理学相结合的方法,确定乌苏里拟鲿对蛋白质、脂肪、适宜的蛋能比、蛋氨酸和赖氨酸的需要量以及对豆粕的利用,为该鱼的配合饲料配制提供依据。具体研究内容和结果如下：1.乌苏里拟鲿肌肉营养成分及品质评价利用常规肌肉营养测定方法,分析了野生和养殖乌苏里拟鲿的肌肉营养成分。结果表明,野生乌苏里拟鲿肌肉中水分的含量(72.91%)显著高于人工养殖乌苏里拟鲿(70.82%)(P<0.05),而粗脂肪含量却显著低于人工养殖乌苏里拟鲿(P<0.05),两者的粗蛋白和灰分含量无显著差异(P>0.05)；野生和养殖乌苏里拟鲿肌肉中氨基酸组成基本一致,均含有16种氨基酸,野生鱼必需氨基酸含量(29.29%)和鲜味氨基酸含量(27.74%)显著高于养殖鱼的必需氨基酸(26.53%)和鲜味氨基酸含量(23.75%)(P<0.05)；野生苏里拟鲿与养殖乌苏里拟鲿的必需氨基酸总量与氨基酸总量的比例分别为42.78%,43.02%,必需氨基酸与非必需氨基酸的比例分别为85.52%和87.74%,其必需氨基酸的构成比例符合联合国粮农组织/世界卫生组织FAO/WHO的标准；按照氨基酸评分(AAS)和化学评分(CS),野生苏里拟鲿与养殖乌苏里拟鲿的限制性氨基酸均为Met+Cys;野生乌苏里拟鲿的∑SFA(31.36%)显著高于养殖乌苏里拟鲿(25.01%),而∑PUFA(11.67%)却显著低于养殖乌苏里拟鲿(17.19%),∑MUFA的差异则不显著,分别为47.92%和48.10%。野生乌苏里拟鲿脂肪酸中EPA和DHA含量分别为1.26%和3.44%,低于养殖乌苏里拟鲿中EPA和DHA的含量(1.8%和5.45%)。综合分析认为,乌苏里拟鲿是营养价值和经济价值较高的优质鱼类。2.乌苏里拟鲿适宜蛋白能量比的研究以乌苏里拟鲿稚鱼(初始体重为3.40±0.01g)为研究对象,研究饲料中不同蛋白、脂肪含量对乌苏里拟鲿生长、饲料利用及体组成的影响。设置4个蛋白质水平(35%、40%、45%和50%),每个蛋白质水平设置3个脂肪水平(5%、10%和15%),配制出12种试验饲料。每个处理设3个重复,每个玻璃缸(150L)25尾乌苏里拟鲿,饱饲投喂,养殖试验持续8周。试验结果表明：在同一蛋白质水平下,增重率(WG)和特定生长率(SGR)随饲料脂肪水平的增加而降低。与5%和10%组相比,脂肪水平为15%饲料组的饲料系数显著高于5%和10%组组(P<0.05),而蛋白质效率和氮沉积率显著降低,5%和10%组之间差异不显著(P>0.05)。在同一脂肪水平下,当饲料中蛋白质水平从35%增加到45%时,WG和SGR均显著升高(P<0.05),当蛋白质水平超过45%后,WG和SGR降低,但是与45%组差异不显著(P>0.05)；当饲料蛋白质含量从35%升高至50%时,蛋白质效率(PER)由198%降至165%,其中,40%、45%和50%组PER分别比35%组降低4.55%、9.09%和16.67%,各组之间差异显著(P<0.05)。饲料中蛋白质、脂肪水平对乌苏里拟鲿摄食率、蛋白质效率和氮沉积率有显著影响(P<0.05),随着蛋白质和脂肪水平的升高而降低。饲料蛋白质和脂肪水平对乌苏里拟鲿全鱼水分的影响不显著(P>0.05)。饲料蛋白质和脂肪水平对乌苏里拟鲿全鱼粗蛋白和粗脂肪影响显著(P<0.05)。在同一脂肪水平下,鱼体中蛋白含量随饲料中蛋白水平的升高而升高,45%组全鱼体蛋白质显著高于35%组和40%组(P<0.05),与50%组差异不显著(P>0.05)。鱼体中脂肪含量随饲料中蛋白水平的升高而显著下降(P<0.05)。在同一蛋白水平下,随着饲料中脂肪水平的升高,鱼体中蛋白含量逐渐下降,而鱼体中脂肪含量逐渐升高。饲料中蛋白质和脂肪水平对全鱼灰分含量无显著影响影响显著(P>0.05)。饲料蛋白质水平对肥满度、肝体比和脏体比均未产生明显的影响(P>0.05)。饲料脂肪水平对肥满度和脏体比均未产生明显的影响(P>0.05),对肝体比影响显著(P<0.05)。3.乌苏里拟鲿赖氨酸需求量的研究以初始体重(0.60±0.00g)的乌苏里拟鲿稚鱼为实验对象,在玻璃缸(1.0×0.5×0.8m3)中进行为期8周的摄食生长实验,研究乌苏里拟鲿稚鱼对饲料中赖氨酸(Lys)的需要量。通过在基础饲料中添加晶体Lys使饲料中Lys含量分别达到1.34%、2.04%、2.74%、3.44%、4.14%和4.84%,配制成6种等氮、等能饲料。每种饲料设3个重复,每个重复随机放养50尾鱼。每天饱饲投喂2次(08：00和16：00)。实验结果表明,各饲料处理组成活率(86.67%-92.67%)无显著差异。当饲料中Lys水平由1.34%(占饲料蛋白3.32%)增加到3.44%(占饲料蛋白8.43%)时,乌苏里拟鲿的增重率、特定生长率和蛋白质效率显著提高(P<0.05),而饲料系数显著降低(P<0.05)；随着饲料Lys水平由3.44%增加到4.84%,乌苏里拟鲿的增重率、特定生长率和蛋白质效率逐渐降低,但均与3.44%组无显著差异。乌苏里拟鲿全鱼、肌肉蛋白质含量随着饲料中Lys水平由1.34%增加到3.44%而显著提高(P<0.05),当Lys水平进一步增加时,乌苏里拟鲿全鱼蛋白质略有降低,但均与3.44%组无显著差异；饲料中Lys水平对乌苏里拟鲿全鱼水分、脂肪、肌肉水分的影响不显著,而随着饲料中Lys水平由1.34%增加到2.74%,肌肉脂肪含量显著升高(P<0.05),之后随着Lys水平的升高而降低。随着饲料中Lys水平由1.34%增加到4.84%,肝体指数逐渐降低,但差异不显著；1.34%组乌苏里拟鲿的肥满度指数显著低于其它组(P<0.05),而其它组之间差异不显著；3.44%和4.14%组的脏体比指数显著低于1.34%、2.04%、2.74%和4.84%组(P<0.05)。根据饲料中Lys水平与乌苏里拟鲿增重率的关系,采用折线模型拟合得出,当增重率达到最大时,饲料中Lys的最适水平为3.38%(占饲料蛋白8.31%)；采用二次回归模型拟合得出,当PER达到最大时,饲料中Lys的最适水平为3.91%(占饲料蛋白9.61%)。4.乌苏里拟鲿蛋氨酸需求量的研究以初始体重(0.60±0.00g)的乌苏里拟鲿稚鱼为实验对象,在玻璃缸(1.0×0.5x0.8m3)中进行为期8周的摄食生长实验,研究乌苏里拟鲿稚鱼对饲料中蛋氨酸(Met)的需要量。通过在基础饲料中添加晶体Met使饲料中Met含量分别达到0.55%、0.85%、1.15%、1.45%、1.75%和2.05%,配制成6种等氮、等能饲料。每种饲料设3个重复,每个重复随机放养50尾鱼。每天饱饲投喂2次(08：00和16：00)。实验结果表明,各饲料处理组成活率(84.67%-91.33%)无显著差异。在饲料中胱氨酸含量为0.25%(占饲料蛋白0.62%)时,当饲料中Met水平由0.55%(占饲料蛋白1.35%)增加到1.15%(占饲料蛋白2.84%)时,乌苏里拟鲿的增重率、特定生长率和蛋白质效率显著提高(P<0.05),而饲料系数显著降低(P<0.05)；之后,随着饲料Met水平由1.15%(占饲料蛋白2.84%)增加到2.05%(占饲料蛋白5.08%),乌苏里拟鲿的增重率、特定生长率和蛋白质效率逐渐降低,而饲料系数显著上升,其中,2.05%组WG、SGR显著低于1.15%、1.45%和1.75%组(P<0.05)。乌苏里拟鲿全鱼、肌肉蛋白质含量随着饲料中Met水平由0.55%增加到1.15%而显著提高(P<0.05),全鱼、肌肉脂肪含量随着饲料中Met水平的增加而提高,当Met水平进一步增加时,脂肪含量降低。饲料中Met水平对乌苏里拟鲿全鱼水分和灰分的影响不显著。1.15%组肌肉水分含量显著低于1.45%组,但与其它组之间差异不显著。1.45%、1.75%和2.05%组肌肉灰分含量显著高于0.85%和1.15%组(P<0.05),但均与0.55%组差异不显著。肥满度随着饲料中Met水平由0.55%增加到1.15%而显著提高,当Met水平进一步增加时,肥满度降低,但与1.15%组无显著差异；肝体比随着Met水平的升高而逐渐降低,其中,0.55%、0.85%、1.15%和1.45%组显著高于1.75%和2.05%组(P<0.05)；0.55%、0.85%、1.15%组脏体指数无显著差异,但均显著高于1.45%、1.75%和2.05%组。根据增重率和饲料中Met水平的关系拟合二次曲线方程得出,当乌苏里拟鲿增重率达到最大时,其饲料中Met的适宜需求量为1.42%(占饲料蛋白3.51%),以蛋白质效率为响应指标时,得出其饲料中Met的适宜需求量为1.39%(占饲料蛋白3.44%)。5.乌苏里拟鲿饲料中豆粕替代鱼粉的研究以豆粕分别替代对照饲料中0%、10%、20%、30%、40%、50%和60%的鱼粉,配制7种等氮、等能试验饲料,另外60%组添加0.3%蛋氨酸。以初始体重0.50±0.00g的乌苏里拟鲿稚鱼为试验对象,在室内水族箱中进行为期8周的摄食生长实验。试验结果表明,豆粕替代鱼粉对乌苏里拟鲿的生长性能和饲料利用有显著影响(P<0.05)。随着饲料中SBM替代比例的增大,鱼体的末体重、增重率、特定生长率和蛋白质效率均表现为逐渐降低,但S10、S20、S30、S40与S0之间差异不显著,S50、S60显著低于S0组(P<0.05),末体重和特定生长率S20、S30、S40、S50与S60之间差异不显著,S60组添加晶体蛋氨酸后,其末均重、增重率和特定生长率与S60相比有所提高,但与其无显著差异,且与S20、S30、S40、S50之间无显著差异,但还是显著低于S0组(P<0.05)；饲料系数的变化规律与增重率的趋势正好相反；当饲料中SBM替代水平由0%增加到20%时,乌苏里拟鲿的摄食率由3.22%提高到3.55%,而后随着替代比例进一步增加,摄食率逐渐降低,但单因素方差分析表明,差异不显著；这一结果表明,豆粕可以替代乌苏里拟鲿饲料中40%鱼粉蛋白,并没有对乌苏里拟鲿的生长和饲料利用产生不利影响,此替代比例下。饲料中鱼粉和豆粕的含量分别为30%和28.4%。饲料中豆粕替代鱼粉对乌苏里拟鲿全鱼水分和灰分含量的影响不显著,而随着替代比例的升高,肌肉水分逐渐升高,其中,S0组最低；全鱼、肌肉蛋白质含量随着替代比例的升高而逐渐降低,其中,S0、S10、S20、S30、S40和S50组间差异不显著,但均显著高于S60和S60+Met组(P<0.05),随着饲料中豆粕替代鱼粉比例的升高,全鱼、肌肉脂肪呈现升高的趋势,其中,S60和S60+Met组显著高于其它替代组(P<0.05),从本试验结果可知,乌苏里拟鲿的肥满度有随着豆粕替代比例的增加而降低的趋势,但在组间差异不显著；在0～50%替代组,肝体比、脏体比指数差异不显著,但是当SBM替代鱼粉比例为S60%时,肝体比、脏体比指数显著升高(P<0.05),这表明高比例豆粕替代鱼粉会影响肝脏的形态。饲料中豆粕替代鱼粉对乌苏里拟鲿营养物质表观消化率影响显著(P<0.05)。当替代水平由0%升高到40%时,各实验组干物质消化率差异不显著,50%,60%组的干物质的表观消化率显著降低(P<0.05)；蛋白质的表观消化率随着替代比例的增加呈现逐渐降低的趋势,替代比例小于40%时,各实验组蛋白质消化率差异不显著,而50%和60%组显著降低(P<0.05),在本实验中,随着SBM替代比例由0%升高到60%,磷表观消化率由36.07%升高到66.50%。饲料中豆粕替代鱼粉对乌苏里拟鲿氮、磷排泄的影响显著(P<0.05)。随着豆粕替代水平的增加,氮排泄逐渐升高,而氮的沉积率则表现出逐渐降低的趋势。其中,S20、S30、S40、S50和S60组的氮排泄差异不显著,但均显著高于S0组和S10组(P<0.05)；氮沉积率则表现出逐渐降低的趋势；其中,S0与S10、S20、S40和S50组间差异不显著,显著高于S30和S60组(P<0.05),60%组添加蛋氨酸后,显著提高氮沉积率,对氮排泄无显著影响,随着豆粕替代水平的增加,磷排泄显著降低,而磷的沉积率则表现出显著升高的趋势(P<0.05)。更多还原

【Abstract】 Pseudobagrus ussuriensis is one of the most important indigenous species in the northeast of China. Pseudobagrus ussuriensis is a Siluriformes species with high potential for aquaculture exploitation in China due to its excellent taste, high market value, high resistance against diseases and availability of reproduction technology. So far, no nutritional studies have been conducted to determine the nutritional requirements of this fish, and there are no commercially available feeds specifically formulated for this fish, which is a limiting factor for the development of this species reared in aquaculture. The present study was carried out to compare the nutritional composition of farmed and wild Pseudobagrus ussuriensis muscles, to evaluate the optimum protein and energy levels, lysine and methionine requirements, and utilization of soybean meal of Pseudobagrus ussuriensis for developing cost-effective and nutritionally balanced diets. The Results of the study are presented as follows:1. Comparative study of nutritional composition of farmed and wild Pseudobagrus ussuriensis musclesThe nutritional composition of the muscle of wild Pseudobagrus ussuriensis and farmed fish were compared. The lipid content of the farmed fish was significantly higher, while moisture content was significantly lower, than those of the wild fish (P<0.05). Pseudobagrus ussuriensis protein has a well-balanced amino acid composition. The amino compositions of the two groups are also including16kinds of amino acids (tryptophan was not measured). The percentages of total amino acids, total essential amino acids, total nonessential amino acids and total delicious amino acids were significantly higher in the wild than those in farmed fish. The ratios of WEAa/WTAA (42.78%～43.02%) and WEAA/WNEAA (85.52%～87.74%) were comparable to the reference values of40%and above60%recommended by FAO/WHO. According to the amino acid scores, methionine and cystine would has been described as the first limiting amino acid, and Lys had the highest score for the proteins in both wild and farmed Pseudobagrus ussuriensis. Total saturated fatty acids (SFAs) were higher in the wild fish comparing to cultured fish, whereas its total polyunsaturated fatty acids (PUFAs) was lower, and monounsaturated fatty acids (MUFAs) did not differ significantly between farmed and wild fish. This study shows that Pseudobagrus ussuriensis under investigation have high nutritional qualities and are good protein resources.2. Effects of dietary protein and lipid levels on growth, feed utilization and body composition in Pseudobagrus ussuriensis fingerlingsAn8-week feeding trial was conducted to investigate the optimum dietary protein and lipid levels for growth, feed utilization and body composition of Pseudobagrus ussuriensis fingerlings (initial weight:3.40±0.01g). Twelve diets containing four protein levels (350,400,450and500g kg-1crude protein) and three lipid levels (50,100and150g kg-1crude lipid) were formulated. Fish were randomly allotted to36aquaria (1.0x0.5x0.8m) with25fish to each glass aquarium. Fish were fed twice daily (08:00and16:00) to apparent satiation. The results showed that weight gain and specific growth rate (SGR) decreased with increasing dietary lipid level from50to150g kg-1at the same dietary protein level. Fish fed the diets containing150g kg-1lipid exhibited higher FCR (p<0.05), lower protein efficiency ratio (PER) and nitrogen retention efficiency (NRE) relative to fish fed the diet containing50and100g kg-1lipid. Weight gain and SGR significantly increased with increasing dietary protein from350to450g kg-1at the same dietary lipid level, and even a little decline in growth with the further increase of dietary protein to500g kg-1. PER decrease with increasing dietary protein and lipid levels (Table3). PER of fish fed the350,400,450g kg-1protein diet with150g kg-1lipid was significantly (P<0.05) lower than that of fish fed the50g kg-1or100g kg-1lipid diet. Daily feed intake, NRE and PER were significantly affected by both dietary protein and lipid levels (p<0.05), and tended to decrease with increasing dietary protein and lipid levels.No significant differences among treatments were detected for moisture content in whole body samples (P>0.05). Whole body protein content increased as protein levels increased and lipid levels decreased. Whole body lipid and muscle lipid content increased with increasing dietary lipid level, and decreased with increasing dietary protein at each lipid level. There were no significant difference in condition factor and viscerosomatic index among fish fed the diets. Hepatosomatic index was affected by dietary lipid level (P<0.05), and increased with increasing dietary lipid level at the same protein level. No significant differences among treatments were detected for moisture, protein and ash content in muscle samples (p>0.05). Muscle protein content increased as protein levels increased at the same lipid level. Muscle lipid content was affected by dietary protein and lipid level (P<0.05), and increased as lipid levels increased and protein levels decreased.3. Dietary lysine requirement of juvenile Pseudobagras ussuriensisAn8-week feeding experiment was conducted to estimate the dietary lysine requirement of juvenile Pseudobagras ussuriensis with an initial average weight of0.60g reared in indoor flow-through and aerated aquaria (1.0x0.5x0.8m3). Six isonitrogenous and isolipidic diets containing six levels of dietary lysine levels ranging from1.34%to4.84%(dry weight) at about 0.7%increments were formulated. Equal amino acid nitrogen was maintained by replacing lysine with nonessential amino acid mixture. Triplicate groups of50fish were fed to apparent satiation by hand twice daily (08:00and16:00). No significant differences were observed in survival rates of fish (86.67%～92.67%), but specific growth rate (SGR), weight gain (WG), feed conversion ratio (FCR) and protein efficiency ratio (PER) were significantly affected by different dietary lysine levels (P<0.05). Weight gain (WG), SGR and PER increased, while FCR decreased with increasing dietary lysine level up to3.44%(8.43%of the dietary protein), and then leveled off. The whole body and muscle crude protein contents increased significantly with dietary lysine levels from1.34%to3.44%(P<0.05), and decreased with dietary lysine levels from3.44%to4.84%(P>0.05). Moisture and lipid content in whole body, moisture content in muscle were not affected by dietary lysine level. The muscle lipid contents increased significantly with dietary lysine levels from1.34%to2.74(P<0.05), and thereafter, remained nearly the same. The hepatosomatic index was negatively correlated with dietary lysine levels, but no significant differences were observed. CF and VSI were significantly affected by dietary lysine levels. CF of1.34%treatments were significantly lower than the other treatments (P<0.05). VSI of3.44%and4.14%treatments were significantly lower than those of fish fed diets1.34%,2.04%,2.74%and4.84%group (.P<0.05). Broken-line analysis on the basis of weight gain showed that the dietary lysine requirement of juvenile Pseudobagras ussuriensis was3.38%of dry diet (8.31%dietary protein); Quadratic regression analysis of PER against dietary lysine levels indicated that the optimal dietary lysine requirement for maximum growth and feed utilization of juvenile Pseudobagras ussuriensis is3.91%of dry diet (9.61%dietary protein).4. Dietary methionine requirement of juvenile Pseudobagras ussuriensisAn8-week feeding experiment was conducted to estimate the dietary methionine requirement of juvenile Pseudobagras ussuriensis with an initial average weight of0.60g reared in indoor flow-through and aerated aquaria (1.0x0.5x0.8m3). Six isonitrogenous and isolipidic diets containing six levels of dietary methionine levels ranging from0.55%to2.05%(dry weight) at about0.3%increments were formulated at a constant dietary cystine level of0.25%. Equal amino acid nitrogen was maintained by replacing lysine with nonessential amino acid mixture. Triplicate groups of50fish were fed to apparent satiation by hand twice daily (08:00and16:00). No significant differences were observed in survival rates of fish (84.67%～91.33%), but specific growth rate (SGR), weight gain (WG), feed conversion ratio (FCR) and protein efficiency ratio (PER) were significantly affected by different dietary methionine levels (P<0.05). WG, SGR and PER increased, while FCR decreased with increasing dietary methionine level from0.55%to1.15%(P<0.05), however, with further increase in dietary methionine level from1.15%to2.05%, WG, SGR and PER significantly decreased, while FCR increased (P<0.05). The whole body and muscle crude protein contents increased significantly with dietary methionine levels from0.55%to 1.15%(P〈0.05), and decreased with dietary methionine levels up to2.05%. The whole body and muscle lipid contents increased significantly with dietary methionine levels, and thereafter decreased. Moisture and ash content in whole body were not affected by dietary methionine level. The muscle moisture content of1.15%group was significantly lower than the1.45%group (P〈0.05). The muscle ash content of1.45%,1.75%and2.05%group were significantly higher than the0.85%and1.15%group (P〈0.05). CF increased with increasing dietary methionine levels from0.55%to1.15%(P〈0.05) and then decreased with further increase to2.05%(P>0.05). HSI of0.55%,0.85%,1.15%and1.45%groups were significantly higher than those of fish fed diets1.75%and2.05%groups (P〈0.05). VSI of0.55%,0.85%and1.15%groups were significantly higher than those of fish fed diets1.45%,1.75%and2.05%groups (P〈0.05). Quadratic regression analysis of weight gain and PER gainst dietary methionine levels indicated that the optimal dietary methionine requirement for maximum growth and feed utilization of juvenile Pseudobagras ussuriensis were1.42%and1.39%dry diet (3.51%and3.44%dietary protein), respectively in the presence of0.25%cystine.5. Fish meal replacement by soybean meal in diets for juvenile Pseudobagras ussuriensisAn8-week feeding experiment was conducted in indoor culture system to evaluate the effects of replacing fish meal with soybean meal (SBM) in feeds for juvenile Pseudobagras ussuriensis. Triplicate groups of juvenile Pseudobagras ussuriensis (initial weight of0.5g) were fed one of eight experimental diets which were formulated to replace FM protein by SBM at0%,10%,20%,30%,40%,50%or60%(designated as SO, S10, S20, S30, S40, S50or S60, respectively). To investigate the effects of supplementation with crystalline amino acid mixture (CAA) to balance Diet S60, one diet was formulated to add0.3%methionine (SM60). Growth, feed utilization were significantly affected by dietary SBM replacement level (P<0.05). Weight gain (WG), specific growth rate (SGR) and protein efficiency ratio (PER) linearly decreased with increasing SBM replacement level from0to60%, however, there were no significant differences in WG, SGR and PER between fish fed the control diet and feeds in which SBM replaced10to40%of the fish meal (P>0.05), but fish fed the diets S50and S60had lower WG, SGR and PER than the diet SO (P〈0.05). Supplementation with CAA improved growth and feed efficiency, however, there were no significant differences in growth between fish fed the diet S60and diet SM60(P>0.05), and significantly lower than those in fish fed diet SO. Feed conversion ratio (FCR) had an opposite trend with WG and SGR. There was no significant difference in feeding intake (FI) among fish fed the different diets. Moisture and ash content in whole body were not affected by dietary SBM replacement level. The muscle moisture content of diet SO was significantly lower than the other groups (P〈0.05). The whole body and muscle protein contents decreased with the increase of dietary SBM level, and fish fed the feeds in which SBM replaced0to50%of the fish meal had higher protein content than that of fish fed the diets S60and SM60(P〈0.05). The whole body and muscle lipid contents increased with increasing dietary SBM level, and S60and SM60groups were significantly higher than the other groups (P<0.05). The CF was inversely correlated with the SBM replacement level, but no significant difference was found among the dietary treatments. Fish fed the diets S60and SM60had higher VSI and HSI than those of fish fed the diets in which0to50%of the fish meal was replaced (P<0.05), and no significant difference in VSI and HSI among fish fed the diets S0-S50was found. The ADC of protein and dry matter of the diet S50and S60were significantly lower than that of the other diets (P0.05), while no significant differences were found among the other diets (P>0.05). The ADC of phosphorus significantly increased with an increase of SBM incorporation in the diet (P<0.05). Phosphorus excretion significantly decreased with increasing levels of SBM replacement (P<0.05), while phosphorus retention increased with increasing levels of SBM replacement from0to60%. Fish fed the diets SO and S10had lower nitrogen excretion than those of fish fed the diets in which20to60%of the fish meal was replaced (P<0.05). Fish fed the diets S30and S60had lower nitrogen retention than those of fish fed the other diets (P<0.05). The results of this study show that SBM is an acceptable ingredient to replace40%of fish meal in Pseudobagras ussuriensis diets, but that higher dietary levels reduce fish performance under the experimental conditions used in this study.更多还原