【摘要】 奥尼罗非鱼(Oreochromis niloticus×O.aureus)幼鱼的初始体重约5.0 g,试验共设5组饲料,以全鱼粉饲料为对照组(D0),以豆粕和花生粕完全替代鱼粉为试验组,其中两组为不补充磷酸二氢钙的情况下不添加植酸酶(D1)和添加植酸酶(D2),另两组为在补充磷酸二氢钙的情况下不添加植酸酶(D3)和添加植酸酶(D4)。每一饲料组设3个重复,每箱养鱼30尾,在流水系统中饲养,表观饱食投喂,投喂率为5%~6%。饲养实验周期为8周。试验结果表明,添加磷组(D3、D4)和全鱼粉组(D0)的特定生长率和饲料系数在组间差异不显著(P>0.05),但显著高于不添加磷组(D1、D2)(P<0.05);磷的表观消化率在添加植酸酶组(D2、D4)均显著高于不添加植酸酶(D1、D3),但与全鱼粉组(D0)差异不显著;鱼体粗蛋白含量在不添加磷和植酸酶组(D1)显著低于其他4组;体粗脂肪含量在不添加磷(D1、D2)组显著高于其他组;体灰分含量由高到低依次为全鱼粉组(D0)、添加磷和植酸酶组(D4)、添加磷不添加植酸酶组(D3)、不添加磷添加植酸酶组(D2)和不添加磷不添加植酸酶组(D1),且两两组间差异显著;体钙、磷、镁、锌含量和脱脂骨灰分、钙、磷含量在全鱼粉组(D0)最高。不添加磷组(D1、D2)血清磷含量显著低于其他3组,而血清碱性磷酸酶活性显著地高。试验结果说明,无鱼粉饲料中补充磷可保持奥尼罗非鱼幼鱼生长率,饲料利用和全鱼可食部分营养成分含量;同时添加植酸酶,能显著提高饲料中磷的利用率,促进磷、锌和镁在鱼体内沉积,并有进一步提高奥尼罗非鱼幼鱼生长和饲料利用的趋势。[中国水产科学,2006,13(1):112-118]更多还原

【Abstract】 An 8-week feeding trial was conducted to investigate growth,feed utilization and body composition of juvenile tilapia Oreochromis niloticus×O.aureus(with initial body weight of 5.0?g) fed on fishmeal-free diets with supplements of inorganic phosphorus and phytase.Five test diets were formulated in which fishmeal diet(D0) was applied as control.Fishmeal-free diets were supplemented without phytase(D1),and with phytase(D2),with monobasic calcium phosphate alone(D3) and with monobasic calcium phosphate and phytase as well(D4).Each test diet was fed to three replicate tanks of fish.Thirty fish were randomly stocked into each tank and reared in a flowthrough system for eight weeks.Feeding rate was 5%-6% of body weight to apparent satiation.The results showed that specific growth rate and feed efficiency in the fish fed on the diets with P supplements(D3 and D4) were not significantly different from that in the fish fed on the fishmeal diet(D0)(P>0.05),but significantly higher than that in the fish fed on the diets without P supplements(D1 and D2)(P<0.05).Significantly higher apparent digestibility of phosphorus was observed in the fish fed on diets with phytase supplements(D2 and D4) than that in the fish fed on the diets without phytase supplements(D1 and D3),but no significant differences were observed in the fish fed on the fishmeal diet(D0).Body crude protein content in the fish fed on the diet without P and phytase supplements(D1) was significantly lower than that in the fish fed on the other test diets(D0,D2,D3 and D4).Body crude lipid contents in the fish fed on diets without P supplements(D1 and D2) were significantly higher than that in the fish fed on the other test diets(D0,D3 and D4).Body ash contents were in the following descending order: D0,D4,D3,D2 and D1,and significant differences were observed among treatments.The contents of body Ca,P,Mg,Zn and the contents of ash,Ca,P in lipid-extracted bone were the highest in the fish fed on the fishmeal diet.The contents of serum phosphorus in the fish fed on the diets without P supplements (D1 and D2) were significantly lower than that in the fish fed on other test diets,whereas the activities of serum alkaline phosphatase were significantly higher.The results indicated that phosphorus supplemented in the fishmeal-free diet could keep the growth,feed utilization and the contents of nutritional composition of body edible part.Phytase supplemented in the fishmeal-free diets with P at the same time could increase dietary P utilization and the deposition of P,Mg and Zn in body,and further increase growth and feed utilization in juvenile tilapia.[Journal of Fishery Sciences of China,2006,13(1):112-118]更多还原