【作者】 钟观运；

【导师】 邵庆均；

【作者基本信息】 浙江大学 ， 动物营养与饲料科学， 2009， 硕士

【摘要】 磷元素是水产动物所不可缺少的重要营养元素,大部分水产动物的配合饲料中都添加磷以提高水产动物的生产性能。本试验以黑鲷幼鱼为试验对象,在水温为28±1℃、盐度为26～29‰、溶氧为5.0mg/L以上的养殖水体中,研究饲料中添加不同磷源对黑鲷幼鱼生长、鱼体常规营养成分含量、组织磷含量以及组织生化指标的影响和黑鲷幼鱼对不同磷源磷的表观消化率。试验选取同一放养批次、体质健康的黑鲷幼鱼,随机分为7组,每组三个重复,每个重复25尾,平均每尾体重13.32±0.11g,进行为期56d的养殖试验。其中的一组作为对照组(T1),对其投喂总磷含量为0.72%的基础饲料；对另外的6组试验组,分别在黑鲷幼鱼饲料中添加磷酸二氢钠、磷酸氢二钠、磷酸钠达到磷含量1.4%(T2-T4)和1.8%(T5-T7)两个总磷水平。试验最后三周,采集黑鲷幼鱼采食后4小时左右的新鲜粪便,分析黑鲷幼鱼对饲料中各种营养成分的表观消化率。养殖试验结束后,分析和计算黑鲷幼鱼的饲养指标和饲料指标,并宰杀所有试验鱼,采集全鱼、肝脏、肌肉、脊椎骨、皮肤、鳞片、血清等样品,进行常规营养成分、磷含量和生化指标等的分析。试验结果表明,在饲料中添加不同磷源可以促进黑鲷幼鱼的生长。无论是在黑鲷饲料中添加1.4%还是1.8%磷水平,黑鲷幼鱼成活率、特定生长率显著高于对照组(P<0.05)。在1.4%磷添加水平中,成活率、特定生长率以添加磷酸二氢钠组(T2组)最高,磷酸氢二钠(T3组)次之,磷酸钠(T4组)最低(P>0.05)；在1.8%磷添加水平中,添加磷酸二氢钠组(T5组)的成活率为94.67%,低于磷酸氢二钠(T6组)和磷酸钠(T7组)的97.33%,但各组之间没有显著性差异(P>0.05)。增重率在1.4%磷添加水平中,T2组、T3组显著高于对照组(T1组)和T4组(P<0.05),T2组和T3组以及T1组和T4组之间差异不显著(P>0.05)；而在1.8%磷添加组中,各添加组增重率显著高于对照组(P<0.05),但各添加组之间差异不显著(P>0.05)。腹脂率以基础对照组的3.0%为最高,显著高于除T4组之外的其它磷添加组(P<0.05)；在1.4%和1.8%两个添加水平中,都以磷酸二氢钠、磷酸氢二钠、磷酸钠顺序升高,T4组腹脂率显著高于T2组和T3组(P<0.05),而T5组、T6组、T7组之间差异不显著(P>0.05)。肝体指数以对照组的1.91为最高,显著大于除T4组之外的其它添加组(P<0.05)；在1.4%添加水平中,T3组、T4组显著大于T2组(P<0.05),T3组和T4组之间差异不显著(P>0.05)；在1.8%添加水平中,T5组、T6组、T7组的肝体指数差异不明显(P>0.05)。饲料系数对照组(1.70)显著高于除T4组(1.65)之外的其它添加组(P<0.05)；在1.4%添加水平中,T2组和T3组的饲料系数显著低于T4组(P<0.05)；在1.8%添加水平中,各添加组差异不显著(P>0.05)。在肌肉的脂肪含量中,T1组的含量显著高于T2组、T3组、T5组、T6组和T7组(P<0.05),但与T4组差异不显著(P>0.05)。在肝脏脂肪含量中,对照组脂肪含量为25.90%,显著高于各添加组(P<0.05)；在1.4%添加水平中,T2组脂肪含量为17.78%显著低于T4组(P<0.05),但与T3组差异不显著(P>0.05)；在1.8%添加水平中,各组脂肪含量以T5组、T6组、T7组顺序递增,但各组之间差异并不显著(P>0.05)。黑鲷幼鱼脊椎骨、皮肤、鳞片的灰分、磷、钙以及钙磷比基本呈一致的变化趋势。对照组(T1组)由于饲料中的总磷含量较低,黑鲷幼鱼的脊椎骨、皮肤、鳞片的灰分、磷、钙以及钙磷比都比其他各组低；在1.4%和1.8%两个添加水平中,黑鲷幼鱼的脊椎骨、皮肤、鳞片的灰分、磷、钙以及钙磷比基本以磷酸二氢钠(T2组、T5组)、磷酸氢二钠(T3组、T6组)、磷酸钠(T4组、T7组)为顺序递降。各组饲料的干物质表观消化率差异不明显(P>0.05)。在1.4%添加水平中,T2组的蛋白质表观消化率明显高于T4组(P<0.05),但与T3组差异不明显(P>0.05)；在1.8%添加水平中,各组黑鲷幼鱼对蛋白质的表观消化率差异不显著(P>0.05)。T1组的脂肪消化率为88.21%,显著低于其它各组(P<0.05)：在1.4%添加水平中,T2组和T3组的脂肪表观消化率显著高于T4组(P<0.05),而1.8%添加水平的T5组、T6组和T7组的脂肪表观消化率差异不显著(P>0.05)。磷的表观消化率以对照组的90.30%为最高,显著高于T4组(P<0.05),但与其它磷添加组差异不显著(P>0.05)；在1.4%添加水平中,磷的表观消化率以T2组、T3组、T4组的顺序递减,但各组之间差异不明显(P>0.05)；1.8%添加水平磷的表观消化率变化趋势和差异显著性同1.4%添加水平。血清中的总葡萄糖含量以T1组最高,且显著高于各添加组(P<0.05)；在1.4%添加水平中,总葡萄糖含量以T2组、T3组、T4组顺序递增,但各组之间差异不显著(P>0.05)；在1.8%添加水平中,总葡萄糖含量以T5组、T6组、T7组顺序递增,T7组显著高于其它各组(P<0.05),但T5组、T6组之间差异不显著(P>0.05)。T1组总胆固醇的含量为8.70mmol／L,显著高于T2组、T5组、T6组和T7组(P<0.05)；在1.4%添加水平中,T2组的总胆固醇含量显著低于T3组和T4组(P<0.05),但T3组和T4组之间差异不显著(P>0.05)；在1.8%添加水平中,T5组的总胆固醇含量显著低于T6组和T7组(P<0.05),但T6组和T7组之间差异不显著(P>0.05)。T1组甘油三酯含量为13.93mmol／L,显著高于其它各组(P<0.05)；在1.4%和1.8%两个磷添加水平中,磷酸二氢钠添加组(T2组、T5组)的甘油三酯含量显著低于磷酸氢二钠(T3组、T6组)和磷酸钠(T4组、T7组)组(P<0.05)。黑鲷幼鱼血清、肝脏、肌肉中的AKP活力都以T1组为最高,且1.4%和1.8%两个磷添加水平中的变化趋势一致,都以磷酸二氢钠、磷酸氢二钠、磷酸钠顺序递增,但差异显著性因组织而各异。血清中的AKP活力各组之间差异不显著(P>0.05)。在1.4%添加水平的肝脏中,T4组显著高于T2组和T3组(P<0.05),T2组和T3组之间差异不显著(P>0.05)；而在1.8%添加水平的肝脏中,T7显著高于T5组(P<0.05),T6组与T5组、T7组之间差异都不显著(P>0.05)。在1.4%磷添加水平的肌肉中,AKP活力差异显著性同肝脏；而在1.8%添加水平的肌肉AKP活力中各组之间差异显著(P<0.05)。以特定生长率、脊椎骨磷含量、血液碱性磷酸酶等为指标,无论是在1.4%还是在1.8%磷添加水平中,不同磷源对黑鲷幼鱼的影响顺序为：磷酸二氢钠>磷酸氢二钠>磷酸钠。更多还原

【Abstract】 Phosphorus is an essential nutrient for aquatic animals, it plays an important role in the metabolism of carbohydrate, lipid and amino acids, as well as various metabolic processes involving buffers in body fluids. Although animals can absorb it from natural water, food is the main source of phosphorus because of its low concentration in water as well as low absorption rate of phosphorus from the water.This trial was conducted to research the effect of various phosphorus sources on growth performance, body composition, tissue phosphorus content, biochemical indices and phosphorus apparent digestibility in juvenile black sea bream (Sparus macrocephalus). The fish were reared in seawater (salinity,26～29‰) at a temperature of 28±1℃. Dissolved oxygen during the experiment was above 5 mg·l-1.The black sea bream juveniles were randomly allotted to seven groups with three replicate. Each replicate consisted of 25 fish with mean weight of 13.32±0.11g. One group was fed basal diet (T1), which contained 0.72% total phosphorus; T2-T7 groups were fed experimental diets with three phosphorus sources (mono-sodium phosphate, di-sodium phosphate, tri-sodium phosphate) in 1.4% and 1.8% total phosphorus. The faeces samples were collected in the last three weeks. After 8 weeks fed, fish were killed to collect the carcass, liver, muscle, vertebra, skin, scales and plasma samples, and then analyzed the collected samples for body composition, phosphorus content and biochemical indices.The results showed that the supplementation of different phosphorus sources could improve the growth performance of black sea bream. At the 1.4% phosphorus level, survival rate and special growth rate were highest with the mono-sodium phosphate (T2), then di-sodium phosphate (T3), tri-sodium phosphate (T4) was the lowest (P>0.05); however at the 1.8% phosphorus level, survival rate of T2 was 94.67%, lower than 97.33% of the T3 and T4, but there was no significant difference between each other(P>0.05). Weight gain ratio (WGR) of T2 and T3 were significantly higher than T1 and T4 (P<0.05); WGR of all treatment of the 1.8% phosphorus level were significantly higher than T1 (P<0.05), however there were no significant differences for each other (P>0.05). The basal diet group (T1) had a highest intraperitoneal fat ratio (IPF) 3.0%, it significantly higher than experimental diets except T4 (P<0.05); Both at the 1.4% and 1.8% phosphorus level, IPF range in mono-sodium phosphate, di-sodium phosphate, tri-sodium phosphate. IPF of T4 was significantly higher than T2 and T3 (P<0.05) at 1.4% phosphorus level, while there are no significant differences between each other at 1.8% phosphorus level (P>0.05). Hepotasomatic index (HSI) of T1 was 1.91, and significantly higher than c phosphorus treatments except T4 (P<0.05); at 1.4% phosphorus level, HSI of T2 was significantly lower than T3 and T4 (P<0.05), while there was no significant difference between T3 and T4 (P>0.05). Feed index of T1 was 1.70, and significantly higher than other treatments except T4 (P<0.05); Feed index of T2 and T3 were significantly higher than T4 (P<0.05), there were no significant differences for each other treatment at the 1.8% phosphorus level (P>0.05). There were no significant differences to the body composition of juvenile black sea bream by added diets (P>0.05).Lipid in muscle of T1 was significantly more than T2, T3, T5, T6 and T7 (P<0.05), while it was no significant difference with T4(P>0.05). Liver lipid of T1 is 25.90%, and significantly higher than all the treatments (P<0.05). Lipid of T2 was 17.78%, and lower than T4 (P<0.05), while there was no significant difference with T3 (P>0.05). There were no significant differences between each others at the 1.8% phosphorus level (P>0.05).Ash, phosphorus, calcium and Ca/P of vertebra, skin and scale turn the same tendency. Ash, phosphorus, calcium and Ca/P of vertebra, skin and scale of T1 were lower than other treatments because of low phosphorus content in diet (P<0.05). It was range in mono-sodium phosphate, di-sodium phosphate, tri-sodium phosphate both at 1.4% and 1.8% phosphorus level.Apparent digestibility (AD) of dry matter had no significant difference between each experimental diet groups (P>0.05). Apparent digestibility of protein of T2 was significantly higher than T4 (P<0.05), while it was no significant difference with T3 (P>0.05); there was no significant difference between each treatment at 1.8% phosphorus level (P>0.05). Lipid digestibility of T1 was 88.21%, it significantly higher than other groups (P<0.05); apparent digestibility of lipid of T4 was significantly lower than T2 and T3 (P<0.05), while there were no significant differences between each other at 1.8% phosphorus level (P>0.05). Apparent digestibility of phosphorus of T1 is 90.30%, it was the highest among all the treatments and significantly higher than T4 (P>0.05), however it no significant difference with other treatments (P>0.05). Apparent digestibility of phosphorus was range in mono-sodium phosphate, di-sodium phosphate, tri-sodium phosphate both at 1.4% and 1.8% phosphorus level, while there were no significant differences between each others (P>0.05).Glucose content of serum of T1 was significantly higher than all the treatments (P<0.05). The glucose content of serum was range in mono-sodium phosphate, di-sodium phosphate, tri-sodium phosphate both at 1.4% and 1.8% phosphorus level. There were no significant different between in T2, T3 and T4, as well as T5 and T6 (P>0.05), while T7 was significant difference from with T5 and T6 (P<0.05). Total Cholesterol (T-CHO) of T1 was 8.70mmol, and significantly higher than T2, T5, T6and T7(P<0.05). T-CHO of T2 was significantly lower than T3 and T4 at 1.4% phosphorus level (P<0.05), while there was no significant difference between T3 and T4 (P>0.05). T-CHO of T5 was significantly lower than T6 and T7 at 1.4% phosphorus level (P<0.05), while there was no significant difference between T6 and T7 (P>0.05). TG (Triglyceride) of T1 was 13.93mmol/L, and significantly higher than other treatments (P<0.05). TG of serum of the mono-sodium phosphate was significantly lower than the di-sodium phosphate and tri-sodium phosphate both at 1.4% and 1.8% phosphorus level (P<0.05).Alkaline Phosphatase (AKP) of serum, liver, muscle of T1 was the highest among all the treatments. AKP of serum turns no significant difference (P>0.05). AKP of T4 in liver was significantly higher than T2 and T3 at 1.4% phosphorus level (P<0.05), however there was no significant difference between T2 and T3 (P>0.05). AKP of liver of T7 was significantly higher than T5 (P>0.05), while there were no significant differences between T6 and T5, as well as T7 (P>0.05). AKP of muscle was the same like liver at the 1.4% phosphorus level, while there were no significant differences between each treatment at the 1.8% phosphorus level (P>0.05).SGR, phosphorus content in vertebra and AKP of serum were evaluated as index in black sea bream. Effect of phosphorus sources in black sea bream range in mono-sodium phosphate, di-sodium phosphate, tri-sodium phosphate wherever at 1.4% or at 1.8% phosphorus level.更多还原