【作者】 刘匆；

【导师】 麦康森；

【作者基本信息】 中国海洋大学 ， 水产养殖， 2013， 博士

【摘要】 本文以我国重要的淡水经济养殖鱼类南方鲇(Silurus meridionalis Chen)和鲇catfish (Silurus asotus Linnaeus)为研究对象，在室内流水养殖系统中进行摄食生长实验，分别对南方鲇和鲇的蛋白和脂肪需求、菜粕替代鱼粉蛋白和不同脂肪源对两种鲇鱼成活、生长及饲料利用的影响进行了研究，实验设计和主要研究结果如下：1、以初重约9.2g的南方鲇为研究对象，采用4×3双因素实验设计，配制4个蛋白水平(46%、43%、40%、37%)和3个脂肪水平(13%、10%、7%)共12种实用膨化饲料，在室内流水养殖系统中养殖8周，对南方鲇的蛋白和脂肪营养生理进行研究。结果南方鲇各组间成活率无显著差异(P>0.05)。不同脂肪水平对南方鲇的增重率无显著影响(P>0.05)，不同蛋白水平对南方鲇的增重率影响显著(P<0.05)，且蛋白和脂肪对南方鲇增重率有显著的交互作用(P<0.05)。饲料中脂肪含量为7%时，南方鲇增重率随着蛋白含量的增加而增加，在蛋白含量最大时(46%)增重率达到最大值，显著大于其他各组；在脂肪水平为10%时，南方鲇增重率先升高后降低，在蛋白为43%时达到最大值；而在13%高脂肪组，南方鲇增重率同样呈先升高后降低的趋势，但在蛋白含量为40%时达到最大值。随着饲料中脂肪含量的逐渐增加，南方鲇饲料中最适蛋白水平相应下降，表现出脂肪对蛋白的节约效应，蛋白质的节约效率为62.5%。各组间摄食率1.79-2.12，饲料效率在1.35-1.63，蛋白质效率在3.32-3.78之间(见表2)。膨化饲料中不同蛋白水平显著影响了南方鲇的摄食率、饲料效率和蛋白质效率（P<0.05)。不同脂肪水平对摄食率、饲料效率和蛋白质效率没有显著影响(P>0.05)，蛋白和脂肪对摄食率、饲料效率和蛋白质效率无显著交互作用(P>0.05)。在各个脂肪水平下，摄食率有随蛋白水平增加而呈降低的趋势，两者的相关系数r为-0.811。低蛋白(37%)饲料处理组摄食率最高，显著高于其他蛋白处理组(P<0.05)，而其他蛋白处理组之间无显著差异(P>0.05)。饲料效率的变化趋势与摄食率相反，与饲料中蛋白含量正相关(r=0.820，p=0.000)，即在各个脂肪水平下，饲料效率均随着蛋白水平的增加呈增加的趋势，蛋白质效率与蛋白水平负相关(r=-0.693，p=0.000)。高蛋白高脂肪P46/L13处理组蛋白质效率最低，显著低于其他蛋白处理组(P<0.05)。各组空壳率、肥满度、肝体比均无显著差异(P>0.05)，不同蛋白对脏体比无显著影响(P>0.05)，但不同脂肪水平显著影响了脏体比(P<0.05)，且蛋白和脂肪具有显著交互作用(P<0.05)。当膨化饲料中蛋白水平在37%~43%之间时，不同脂肪处理水平组脏体比差异不显著(P>0.05)，当蛋白水平达到46%时，脏体比随着脂肪水平的增加而增加，且13%脂肪添加组显著大于7%处理组(P<0.05)。综合考虑南方鲇的生长和饲料利用，以及饲料成本和膨化饲料加工的可行性，本实验条件下，南方鲇膨化饲料中适宜的蛋白水平为43%，相应的脂肪添加水平为7%-10%。2、以初重约9.1g的鲇为研究对象，采用4×3双因素实验设计，配制4个蛋白水平(46%、43%、40%、37%)和3个脂肪水平(13%、10%、7%)共12种实用膨化饲料，在室内流水养殖系统中养殖8周，对鲇的蛋白和脂肪营养生理进行研究。鲇各组间成活率和增重率均无显著差异，饲料蛋白和脂肪对成活和生长没有显著交互作用(P>0.05)。饲料中不同蛋白水平显著影响了鲇的摄食率、饲料效率和蛋白质效率(P<0.01)。不同脂肪水平对摄食率、饲料效率和蛋白质效率均无显著影响(P>0.05)。饲料蛋白和脂肪对摄食率、饲料效率和蛋白质效率无显著交互作用(P>0.05)。摄食率与饲料蛋白水平显著负相关(r=-0.622, P=0.000)。在13%和7%脂肪水平处理下，鲇的摄食率均随蛋白水平降低而增加，并在37%蛋白处理组显著高于其他蛋白处理组(P<0.05)；在10%脂肪处理下，尽管差异不显著，37%蛋白处理组的摄食率也明显高于其他蛋白处理组(P>0.05)。鲇饲料效率的变化趋势与摄食率相反(r=-0.980, P=0.000)，与饲料中蛋白含量正相关(r=0.630，P=0.000)，即在各个脂肪水平下，饲料效率均随着蛋白水平的增加呈增加的趋势。鲇蛋白质效率与饲料中蛋白水平负相关(r=-0.488，P=0.003)。P46/L10处理组蛋白质效率最低，显著低于P40/L7和P43/L7(P<0.05)。各组间鲇鱼的生长虽没有显著差异，但37%蛋白处理组饲料效率较低，而46%蛋白处理组蛋白质效率较低。综合考虑饲料中不同蛋白和脂肪水平对生长和饲料利用的影响，认为本实验条件下，鲇膨化饲料中适宜的蛋白水平为40%~43%，相应的脂肪水平为7%-13%。3、以南方鲇为研究对象，以鱼粉、豆粕和菜粕作为主要蛋白源，大豆油为主要脂肪源，面粉提供主要碳水化合物，设计7种实验料，对照组菜粕为0，鱼粉为33%，设置6个菜粕水平(3%、6%、9%、12%、15%、18%)，分别替代4.55%、9.09%、13.64%、18.18%、22.73%、27.27%的鱼粉，补充豆油和磷酸二氢钙平衡能量和磷的差异；替代后总量超出100%，减少面粉用量来平衡。在流水系统中养殖初重约11.4g的南方鲇8周，探讨不同鱼粉替代水平对南方鲇成活、生长和饲料利用及代谢反应的影响。结果如下：南方鲇各组间成活率无显著差异(P>0.05)。南方鲇各组间的特定生长率无显著差异(P>0.05)。南方鲇各组间摄食率、饲料效率和蛋白质效率无显著差异(P>0.05)。南方鲇各组间肌肉水份、粗蛋白、粗脂肪、粗灰分无显著差异(P>0.05)。南方鲇各组间空壳率、肥满度、肝体比无显著差异(P>0.05)。但当替代水平达到27.27%时，脏体比显著增加(P<0.01)。南方鲇各组间血清胆固醇、血清尿素氮、肝脏谷丙转氨酶、肝脏谷草转氨酶无显著差异(P>0.05)。南方鲇各组间胃蛋白酶、肠蛋白酶、胃淀粉酶、肠淀粉酶无显著差异(P>0.05)。结果表明：以33%鱼粉组为对照组，菜粕以2:1比例替代鱼粉，除当替代水平达到22.73%时，脏体比显著增加，各组的生长、成活、饲料利用效率等都没有受到影响，因此在南方鲇膨化饲料中，按2:1比例以菜粕替代鱼粉，替代水平可达到27.27%以上。由于膨化饲料生产工艺的限制，无法进一步得出菜粕可替代鱼粉的更高水平及出现显著差异的水平。4、以鲇为研究对象，以鱼粉、豆粕和菜粕作为主要蛋白源，大豆油为主要脂肪源，面粉提供主要碳水化合物，设计7种实验料，对照组菜粕为0，鱼粉为33%，设置6个菜粕水平(3%、6%、9%、12%、15%、18%)，分别替代4.55%、9.09%、13.64%、18.18%、22.73%、27.27%的鱼粉，补充豆油和磷酸二氢钙平衡能量和磷的差异；替代后总量超出100%的部分，减少面粉用量来平衡。在流水系统中养殖初重约12.3g的鲇8周，探讨不同鱼粉替代水平对鲇成活、生长和饲料利用和代谢反应的影响。结果如下：鲇各组间成活率无显著差异(P>0.05)；菜粕替代鱼粉，只要加入菜粕，即显著降低了鲇的特定生长率(P<0.01)，两者呈负相关（r=-0.815，p=0.000），但各替代水平之间的特定生长率差异不显著(P>0.05)。鲇各组间摄食率、饲料效率和蛋白质效率无显著差异(P>0.05)。鲇各组间干物质表观消化率、蛋白质表观消化率无显著差异(P>0.05)。鲇各组间肌肉水份、粗蛋白、粗脂肪、粗灰分无显著差异(P>0.05)。鲇各组间空壳率、肥满度、肝体比、脏体比无显著差异(P>0.05)。鲇各组间血清胆固醇、血清尿素氮无明显差异(P>0.05)。肝脏谷丙转氨酶随菜粕水平的升高而显著降低，与菜粕替代水平呈负相关，相关系数为r=-0.949（p=0.000），在鱼粉被替代9.09%时显著降低，9.09%-18.18%的替代水平间无显著差异，22.73%的替代水平比9.09%的替代水平显著降低，13.64%-22.73%的替代水平间无显著差异，27.27%的替代水平比13.64%和18.18%替代水平显著降低。肝脏谷草转氨酶在鱼粉被替代18.18%时仍无显著差异(P>0.05)，鱼粉被替代22.73%时，肝谷草转氨酶出现显著下降(，P<0.01)，22.73%和27.27%的替代水平之间则无显著差异(P>0.05)。随着替代水平的升高，胃蛋白酶活性水平呈下降趋势，替代水平与胃蛋白酶活性呈负相关(r=-0.766， p=0.000)，并在鱼粉被替代22.73%、27.27%时分别显著降低。肠蛋白酶活性随替代水平升高呈下降趋势，替代水平与肠蛋白酶活性呈负相关(r=-0.885; p=0.000)，并在替代水平达到18.18%时显著下降，替代水平27.27%时又进一步显著降低。结果表明：鲇膨化饲料中，只要使用菜粕替代，即可降低特定生长率；菜粕替代鱼粉从4.55%-27.27%，各替代水平之间的成活、生长和饲料效率没有显著差异；由于膨化饲料生产工艺的限制，无法进一步得出菜粕可替代鱼粉的更高水平及出现显著差异的水平。5、以南方鲇为研究对象，以鱼粉、豆粕作为主要蛋白源，面粉提供主要碳水化合物，共设置4个组，分别添加4.5%的豆油、鱼油、菜油、牛油作为脂肪源。在流水系统中养殖初重约11.5g的南方鲇8周，探讨不同脂肪源膨化饲料养殖南方鲇成活、生长和饲料利用和代谢反应的差异。结果如下：南方鲇各组间成活率无显著差异(P>0.05)，特定生长率无显著差异(P>0.05)。南方鲇各组间摄食率、饲料效率和蛋白质效率无显著差异(P>0.05)。干物质表观消化率从高到低为菜油组、鱼油组、豆油组、牛油组，其中，菜油组显著高于牛油组(P<0.05)，其他各组间无显著差异。各组间蛋白质表观消化率无显著差异(P>0.05)。南方鲇各组间肌肉水份、粗蛋白、粗脂肪、粗灰分无显著差异(P>0.05)。南方鲇各组间空壳率、肥满度、脏体比、肝体比无显著差异(P>0.05)。南方鲇牛油组的血清胆固醇含量明显高于其他各组(P<0.01)。菜油组的血清尿素氮低于其他三组，显著低于牛油组和豆油组(P<0.01)。各组间肝脏谷丙转氨酶、肝脏谷草转氨酶无显著差异(P>0.05)。南方鲇各组间胃蛋白酶、肠蛋白酶、胃淀粉酶、肠淀粉酶活性无显著差异(P>0.05)。结果表明，本实验中，几种脂肪源的添加量为4.5%，占到饲料总脂肪含量的一半以上，南方鲇各组间成活率、特定生长率、摄食率、饲料效率和蛋白质效率均无显著差异。因此，在生产南方鲇膨化饲料时，添加豆油、鱼油、菜油、牛油均可，不影响成活、生长和饲料利用效率。6、以鲇为研究对象，以鱼粉、豆粕和菜粕作为主要蛋白源，面粉提供主要碳水化合物，共设置4个组，分别添加4.5%的豆油、鱼油、菜油、牛油作为脂肪源。在流水系统中养殖初重约12.3g的鲇8周，探讨不同脂肪源膨化饲料间鲇成活、生长和饲料利用和代谢反应的影响。结果如下：鲇各组间成活率无显著差异(P>0.05)，不同脂肪源对鲇的特定生长率无显著影响(P>0.05)。鲇各组间摄食率从高到低为鱼油>牛油>豆油>菜油，鱼油最高，显著高于其他各组(P<0.01)，牛油次之，显著高于菜油(P<0.01)，植物性油脂间差异不显著(P>0.05)。鲇饲料效率、蛋白质效率从高到低均为菜油>豆油>牛油>鱼油，其中菜油与豆油、牛油差异不显著(P>0.05)，而鱼油显著低于菜油(P<0.05)，饲料效率和蛋白质效率呈正相关，相关系数r=0.990(P=0.000)，两者均与摄食率呈负相关。其中，饲料效率与摄食率相关系数为r=-0.839(P=0.001)，蛋白质效率与摄食率相关系数为r=-0.801(P=0.002)。各组间干物质表观消化率、蛋白质表观消化率无显著差异(P>0.05)。鲇各组间肌肉水份、粗蛋白、粗脂肪、粗灰分无显著差异(P>0.05)。鲇各组间空壳率、肥满度、肝体比无显著差异(P>0.05)。脏体比从高到低为鱼油>牛油>豆油>菜油，与摄食率正相关，相关系数为r=-0.801(P=0.002)，其中鱼油显著高于豆油和菜油(P<0.01)，菜油显著低于鱼油和牛油(P<0.01)。血清胆固醇从高到低为鱼油、菜油、牛油、豆油，鱼油组显著高于其他各组(P<0.01)，血清尿素氮趋势与血清胆固醇相同，从高到低为鱼油、菜油、牛油、豆油，鱼油组与菜油组差异不显著(P>0.05)，但显著高于牛油和豆油组(P<0.05)。鲇各组间胃蛋白酶、肠蛋白酶、胃淀粉酶、肠淀粉酶活性无显著差异(P>0.05)。结果表明：鲇膨化饲料添加豆油、鱼油、菜油或牛油均可。更多还原

【Abstract】 Feeding experiments were conducted to determine the effects of dietary proteinlevels, dietary lipid levels, different protein source, and different lipid source on thegrowth and feed utilization of southern catfish (Silurus meridionalis Chen) andcatfish (Silurus asotus Linnaeus). Results of the studies are presented as follows:1．A4×3two factor experiment was designed to evaluate the optimal dietaryprotein and lipid level for the juveniles of two species of catfish, Silurus meridionalisChen, the initial weight of which was about9.2g. Twelve practical diets wereformulated to contain four protein levels (46%,43%,40%,37%), each with three lipidlevels (13%,10%,7%), using fish meal and soybean meal as protein source, soybeanoil as lipid source. Each diet was fed to a triplicate group of catfish for8weeks in aflow-though water system. The results showed that the weight gain rate (WGR) of S.meridionalis Chen was not significantly affected by dietary lipid (P>0.05). However,dietary protein had significant effects on WGR of S. meridionalis Chen. In the groupwith7%dietary lipid, WGR of S. meridionalis chen firstly increased with theincreasing level of dietary protein, the highest value which was significantly higherthan the other groups (P <0.05) was found in S. meridionalis Chen fed with46%dietary protein level. In the group with10%dietary lipid, WGR of S. meridionalischen firstly increased with the decreasing level of dietary protein, and then decreased,the highest value was found in S. meridionalis Chen fed with43%dietary protein.The same change trend of WGR of S. meridionalis Chen was found in the group with13%dietary lipid, but the highest WGR was found in40%dietary group. With theincreasing level of dietary lipid, the need of maximum dietary protein for S.meridionalis Chen decreased, it was suggested that dietary lipid had protein-sparingeffect on this catfish.Dietary protein significantly affected feed intake (FI), feed efficiency ratio (FER),protein efficiency ratio (PER) of S. meridionalis Chen (P <0.05), but not dietary lipidor their interaction (P>0.05). Among all dietary lipid treatments, FI increased withthe decreasing of dietary protein level (r=-0.811, p=0.000;), and the lowest dietary protein level (37%) significantly increased FI (P<0.05), no significant differenceswere found among the other dietary protein groups.FER had the opposite change trend with FI and was positively related withdietary protein (r=0.820, p=0.000). PER was negatively related with dietary protein(r=-0.693, p=0.000), the group with highest dietary protein and highest dietarylipid (P46/L13) had the lowest PER and significantly lower than the other group(P<0.05).There were no significant differences in deinternal organ ratio, condition factor(CF) and hepatosomatic index (HI). Viscerasomatic index (VI) were significantly(P<0.05) increased by dietary lipid, but not dietary protein. Dietary protein and lipidhad significant effect on HV (P<0.05). when dietary protein level was37%~43%,there were no significant effect on HV among different dietary lipid treatments. Whendietary protein level was46%, the values of VSI significantly increased with theincreasing of dietary lipid levels, moreover, the HV with dietary13%lipid wassignificantly higher than that with dietary7%lipid.Based on the data of WGR, using piece-wise linear analysis, the optimal dietaryprotein for S. meridionalis was40.46%when dietary lipid was7%,43.40%whendietary lipid was10%and46.00%when dietary lipid was13%.Based on the results of WGR, FER, PER, and VI, low dietary protein had thelowest FER. So the optimal dietary protein and lipid requirement of S. meridionaliswas estimated to be43%and7%~10%respectively.2．A4×3two factor experiment was designed to evaluate the optimal dietaryprotein and lipid level for the juveniles of two species of catfish, Silurus meridionalisChen, the initial weight of which was about9.1g. Twelve practical diets wereformulated to contain four protein levels (46%,43%,40%,37%), each with three lipidlevels (13%,10%,7%), using fish meal and soybean meal as protein source, soybeanoil as lipid source. Each diet was fed to a triplicate group of catfish for8weeks in aflow-though water system. The results showed that there were no significantdifference between Survival rate，SR and weight gain rate (WGR) of S. asotusLinnaeu (P>0.05).Dietary protein significantly affected feed intake (FI), feed efficiency ratio (FER),protein efficiency ratio (PER) of S. meridionalis Chen (P <0.05), but not dietary lipidor their interaction (P>0.05). Among all dietary lipid treatments, FI was negatively related with the dietary protein level (r=-0.622, p=0.000;), and when dietary lipidwas13%or7%, the lowest dietary protein level (37%) significantly increased FI(P<0.05); when dietary lipid was10%, the lowest dietary protein level (37%)increased FI although no significant differences were found (P>0.05). FER had theopposite change trend with FI (r=-0.980, p=0.000) and was positively related withdietary protein (r=0.630, p=0.000). Among all the dietary lipid groups, the FERincreased with the increasing level of dietary protein. PER was negatively related withdietary protein (r=-0.488, p=0.000), the group with highest dietary protein anddietary10%lipid (P46/L13) had the lowest PER and significantly lower than P40/L7and P43/L7(P<0.05).Although there were no significant difference in the growth of S. meridionalis,but the group with37%dietary protein had low FER and the group with46%dietaryprotein had low PER. Based on the data of growth and feed utilization, the optimaldietary protein and lipid were estimated to be40%~43%and7%~10%respectively.3. A feeding experiment was studied to determine the effect of dietary rapeseedmeal on the survival, growth and feed utilization of southern catfish Silurusmeridionalis Chen (initial weight about11.5g). Fish meal, soybean meal andrapeseed meal were used as the protein sources. Soybean oil was used as the lipidsource. Wheat meal was used as the carbohydrate source. Seven practical diets wereformulated in a single factor design to contain seven levels of rapeseed meal0%,3%,6%,9%,12%,15%and18%, replacing0%,4.55%,9.09%,13.64%,18.18%,22.73%,27.27%of fishmeal. Each diet was fed to a triplicate group of catfish for8weeks in aflow-though water system. The results showed that there were no significantdifferences in the Survival rate，SR, weight gain ratio (WGR), feed intake (FI), feedefficiency ratio (FER), protein efficiency ratio (PER), and the moisture, crude protein,crude lipid, and ash in muscle (P>0.05). The dietary rapeseed meal had nosignificant effect on the deinternal organ ratio, condition factor, hepatosomatic index(P>0.05). Viscerasomatic index (VI) significantly increased when fish meal wasreplaced27.27%(P <0.05). The cholesterol and urea nitrogen in serum, the alanineaminotransferase and aspartate amino-transferase in liver, pepsin, ereptase, stomachamylase and intestine amylase showed no significant differences in differenttreatments (P>0.05).In conclusion, when dietary rapeseed meal increased to18%, as fish meal was replaced27.27%, there were no significant differences in the growth, survival andfeed utilization, except that VI significantly increased. So it was estimated that thehighest fish meal replacement was27.27%at least according to the results in thisexperimental condition.4. A feeding experiment was studied to determine the effect of dietary rapeseedmeal on the survival, growth and feed utilization of southern catfish Silurus asotusLinnaeus (initial weight about12.4g). Fish meal, soybean meal and rapeseed mealwere used as the protein sources. Soybean oil was used as the lipid source. Wheatmeal was used as the carbohydrate source. Seven practical diets were formulated in asingle factor design to contain seven levels of rapeseed meal0%,3%,6%,9%,12%,15%and18%, replacing0%,4.55%,9.09%,13.64%,18.18%,22.73%,27.27%offishmeal. Each diet was fed to a triplicate group of catfish for8weeks in aflow-though water system.The results showed that there were no significant differences in the survival ofSilurus asotus Linnaeus (P>0.05). However, the supplementation of rapeseed mealsignificant decreased the special growth rate (SGR)(P <0.05). The different level ofdietary rapeseed meal had no significant difference on the SGR (P>0.05). Themoisture, crude protein, crude lipid, and ash in muscle, the feed intake, feed efficiencyratio, protein efficiency ratio, apparent digestibility, apparent protein digestibilityshowed no significant difference between different treatments.The morphological indices, deinternal organ ratio, condition factor,hepatosomatic index, viscerasomatic index showed no significant difference betweendifferent treatments.The supplementation of rapeseed meal decreased the liver alanineaminotransferase significantly (r=-0.949, p=0.000).when fish meal was replaced9.09%, the liver alanine aminotransferase decreased significantly. There was nosignificantly difference between9.09%-18.18%, but22.73%is significantly decreasedthan9.09%. There was no significantly difference between13.64%-22.73%, but27.27%is significantly decreased than13.64%and18.18%. When fish meal wasreplaced22.73%, liver aspirate amino-transferase significantly decreased (P <0.01),There was no significantly difference between22.73%and27.27%. Thesupplementation of rapeseed meal decreased pepsin significantly (r=-0.766，p=0.000), when fish meal was replaced22.73%, pepsin decreased significantly, and when it s reach27.27%, pepsin further significantly decreased. The supplementationof rapeseed meal decreased ereptase significantly too(r=-0.885; p=0.000), when fishmeal was replaced18.18%, ereptase decreased significantly, and when it s reach27.27%, pepsin further significantly decreased.In conclusion, the supplementation of rapeseed meal in extruded feed woulddecrease SGR of Silurus asotus Linnaeus. The supplement of rapeseed meal of3%~18%, replacing4.55-27.27%fish meal, and showed no significant effect on thesurvival, growth and feed utilization.Because the difficulty in extruded production technique, the supplement of morethan18%(replacing more than27.27%fish meal) of rapeseed meal could not be usedin the experiment.5. A single factor experiment was studied to discuss the different lipid source onthe survival, growth and feed utilization of southern catfish Silurus meridionalis Chen(initial weight:11.50±0.02g). Fishmeal and soybean meal were used as the proteinsource, wheat flour was used as carbohydrate source. Four practical diets wereformulated to feed to a triplicate group of catfish for8weeks in a flow-though watersystem. The lipid source was soybean oil, fish oil, rapeseed oil and beef tallowrespectively in four experimental feed.The results showed that the survival and growth had no significant differencebetween different lipid source treatments (P>0.05).There were no significant differences in the feed intake, feed efficiency ratio,protein efficiency ratio between different treatments.The apparent digestibility were rapeseed oil, fish oil, soybean oil and beef tallowfrom high to low, and the value in rapeseed oil group was significantly higher thanthat in the others. There were no significant difference between the fish oil, soybeanoil and beef tallow groups.The four lipid source had no significant effect on moisture, crude protein, crudelipid and ash in the muscle, on the deinternal organ ratio, ondition factor,hepatosomatic index, viscerasomatic index.The serum cholesterol in beef tallow group was significantly higher than that inthe other group (P <0.01). The serum nitrogen in rapeseed oil group was significantlylower than that in beef tallow group and soybean oil group (P <0.01). The liveralanine aminotransferase and liver aspirate amino-transferase showed no significantdifference between different treatments (P>0.05). The pepsin, ereptase, stomach amylase and intestine amylase showed nosignificant differences in different treatments (P>0.05).In the experiment, the supplement of lipid source was4.5%, which is more thanhalf the dietary lipid. Different lipid source had no significant effect on the survival,growth and feed utilization, which suggested that soybean oil, fish oil, rapeseed oiland beef tallow are optimal for Silurus asotus Linnaeus in extruded feed.6. A single factor experiment was studied to discuss the different lipid source onthe survival, growth and feed utilization of southern catfish Silurus asotus Linnaeus(initial weight about12.3g). Fishmeal and soybean meal were used as the proteinsource, wheat flour was used as carbohydrate source. Four practical diets wereformulated to feed to a triplicate group of catfish for8weeks in a flow-though watersystem. The lipid source was soybean oil, fish oil, rapeseed oil and beef tallowrespectively in four experimental feed.The results showed that the survival and growth had no significant differencebetween different lipid source treatments (P>0.05).The feed intake were fish oil, beef tallow, soybean oil and rapeseed oil form highto low, and the value in fish oil group was significantly higher than the other group (P<0.01), beef tallow group was significantly higher than rapeseed oil group (P <0.01).The feed efficiency ratio and protein efficiency ratio were rapeseed oil, soybeanoil, beef tallow oil and fish oil form high to low. There were no significant differencein feed efficiency ratio and protein efficiency ratio between rapeseed oil, soybean oil,beef tallow oil groups, but the fish oil group was significantly lower than rapeseed oilgroup(P<0.05). Moreover, the feed efficiency ratio was positively related with proteinefficiency ratio (r=0.990, p=0000). The feed efficiency ratio and protein efficiencyratio are negatively related with feed intake (r=-0.839, p=0.000; r=-0.801, p=0.002).Different lipid source feed had no significant effect on the apparent digestibilityand protein digestibility respectively (P>0.05).The four lipid source had no significant effect on moisture, crude protein, crudelipid and ash in the muscle, on the deinternal organ ratio, ondition factor,hepatosomatic index. Viscerasomatic index were fish oil, rapeseed oil, beef tallow andsoybean oil from high to low. Viscerasomatic index in fish oil group was significantlyhigher than that in soybean oil and rapeseed oil group (P <0.01), rapeseed oil groupwas significantly lower than that fish oil and beef tallow group(P <0.01).The serum cholesterol were fish oil, rapeseed oil, beef tallow and soybean oil from high to low, and fish oil group was significantly higher than the other group (P<0.01). The serum nitrogen had the same change trend with serum cholesterol, thevalue in fish oil group and rapeseed oil were not significantly different (P>0.05), butboth the two group were significantly higher than beef tallow and soybean oil group(P <0.05).The pepsin, ereptase, stomach amylase and intestine amylase showed nosignificant differences in different treatments (P>0.05).In the experiment, soybean oil, fish oil, rapeseed oil and beef tallow in extrudedfeed had no significant effect on the survival, growth and feed utilization for Silurusasotus Linnaeus.更多还原