【作者】 李华；

【导师】 王小洁； 张文兵；

【作者基本信息】 中国海洋大学 ， 水产养殖， 2011， 硕士

【摘要】 本文以我国重要的鲆碟养殖种类半滑舌鳎(Cynoglossus semilaevis),牙鲆(Paralichthys olivaceus)和大菱鲆(Scophthalmus maximus)为研究对象。在室内流水式养殖系统中进行为期10周的摄食生长实验。探讨饲料中添加维生素C和胆碱分别对半滑舌鳎、牙鲆和大菱鲆生长和生理状态的影响,同时根据不同指标评价了半滑舌鳎对维生素C及牙鲆和大菱鲆对胆碱的需求量。主要研究结果如下:1.实验采用实用饲料,在半滑舌鳎基础饲料中添加0、10、50、150、450、1500mg/kg的维生素C(维生素C多聚磷酸酯形式),制成6种实验饲料,分别对初始体重为(4.21±0.02)g(实验Ⅰ)、(116.93±0.91)g(实验Ⅱ)2个规格各6组半滑舌鳎进行10周的摄食生长实验。每组设3个重复,每个重复分别60尾(实验Ⅰ)、18尾(实验Ⅱ)。实验期间,保持系统黑暗,实验Ⅰ,每天饱食投喂3次(06:00、14:00和22:00),水温变化范围:20~10℃,盐度变化范围:24~26‰,溶氧含量:≥6mg/L,pH:7.9~8.0;实验Ⅱ,每天饱食投喂2次(07:30和18:30),水温变化范围:24.1~18.8℃,盐度变化范围:24~26‰,溶氧含量:≥6mg/L,pH:7.9~8.0。结果表明,实验Ⅰ中,半滑舌鳎的存活率、增重率、特定增长率和饲料转化率随着饲料中维生素C添加量增加,有上升趋势,但差异不显著(P>0.05)。肝脏、肾脏、肌肉中抗坏血酸含量均随饲料中维生素C添加量增加而显著上升(P<0.05)。实验Ⅱ中,半滑舌鳎的存活率、饲料转化率随饲料中维生素C添加量增加有上升趋势,但差异不显著(P>0.05);增重率和特定生长率不受饲料中维生素C显著影响(P>0.05)。当饲料中维生素C添加量超过50mg/kg时,随添加量增加肝脏、肾脏、肌肉中抗坏血酸含量均显著上升并高于对照组(P<0.05)。以上结果表明在本实验条件下,半滑舌鳎幼鱼基础饲料中无需添加额外的维生素C即可满足幼鱼正常生长发育的需要。2.实验采用半精制饲料,在牙鲆基础饲料中添加0、100、300、900、1800、3600 mg/kg的氯化胆碱,制成6种实验饲料,分别含有胆碱260.2、350.4、531.5、1020.9、1914.3和3457.6mg/kg。对初始体重为(3.73±0.04)g的6组牙鲆进行10周的摄食生长实验,每组设3个重复,每个重复20尾鱼。实验期间每天饱食投喂2次(07:30和18:30),水温变化范围:16-20℃,盐度为27‰,pH在7.5～7.8之间,24小时曝气,溶氧含量大于7mg/L,光周期为12h光照:12h黑暗。结果表明:未添加胆碱饲料组牙鲆出现生长下降,饲料转化率低,肠道灰白等缺乏症。饲料中添加胆碱显著提高了牙鲆幼鱼的增重率和饲料转化率(P<0.05),存活率也有上升趋势,但差异不显著(P>0.05)。随着饲料中胆碱水平的升高,牙鲆的WG和FER显著升高(P<0.05),WG在饲料胆碱含量大于等于1914.3mg/kg时,达到稳定状态。牙鲆的肝指数和内脏指数随着饲料胆碱含量的升高而显著降低(P<0.05)。随着饲料胆碱含量升高,牙鲆的体水分含量显著下降(P<0.05),体粗脂肪显著上升(P<0.05)。牙鲆的肝脏和肌肉脂肪不受饲料胆碱显著影响(P>0.05),随着胆碱含量的升高呈上升趋势。随着饲料胆碱水平的升高,牙鲆血浆中总胆固醇和甘油三酯显著上升(P<0.05)。以WG为评价指标,通过折线模型得出牙鲆对胆碱的最适需求量为1707.3mg/kg。3.实验采用半精制饲料,在大菱鲆基础饲料中添加0、100、300、900、1800、3600 mg/kg的氯化胆碱,制成6种实验饲料,分别含有胆碱260.2、350.4、531.5、1020.9、1914.3和3457.6mg/kg。对初始体重为(6.25±0.04)g的6组大菱鲆进行10周的摄食生长实验,每组设3个重复,每个重复30尾鱼。实验期间每天饱食投喂2次(07:30和18:30),水温变化范围:16-19℃,盐度为27‰,pH在7.5～7.8之间,24小时曝气,溶氧含量大于7mg/L,光周期为12h光照:12h黑暗。结果表明:未添加胆碱饲料组大菱鲆出现死亡率高、生长下降,饲料转化率低,肠道灰白等缺乏症。饲料中添加胆碱显著提高了大菱鲆幼鱼的增重率和存活率(P<0.05),饲料转化率也有上升趋势,但差异不显著(P>0.05)。随着饲料中胆碱水平的升高,大菱鲆的WG和SR显著升高(P<0.05),WG在饲料胆碱含量大于等于1914.3mg/kg时,达到稳定状态。大菱鲆的肝指数不受饲料胆碱显著影响(P>0.05),内脏指数随着饲料胆碱含量的升高显著下降(P<0.05)。随着饲料胆碱含量升高,大菱鲆的体水分、灰分含量显著下降(P<0.05),体粗蛋白、体粗脂肪显著上升(P<0.05),当饲料胆碱超过1914.3mg/kg时,体粗脂肪达到稳态。大菱鲆的肝脏脂肪受饲料胆碱显著影响(P<0.05),总体呈先上升后下降趋势。肌肉脂肪随着饲料胆碱含量的升高呈上升趋势,但影响不显著(P>0.05)。随着饲料胆碱水平的升高,大菱鲆血浆中总胆固醇和甘油三酯显著上升(P<0.05),当饲料胆碱大于等于1020.9mg/kg时,血浆甘油三酯达到稳态。分别以WG、体粗脂肪和血浆甘油三酯为评价指标,通过折线模型得出大菱鲆对胆碱的最适需求量分别为2089.8、1800和951.6mg/kg,考虑实际生产意义,推荐饲料中胆碱含量为2089.8mg/kg。更多还原

【Abstract】 Ten-week feeding trials were conducted to investigate the nutritional physiology of vitamin C for tonguefish (Cynoglossus semilaevis) and choline for flounder (Paralichthys olivaceus) and turbot (Scophthalmus maximus). The feeding trials were conducted in indoor floating water culture system. The dietary requirements of vitamin C for tonguefish and choline for flounder and turbot were estimated using different indicators. Results of these studies are presented as follows:1. Six practical diets were designed with 0, 10, 50, 150, 450 and 1500 mg ascorbic acid equivalent kg-1 supplemented respectively to the basic diet, as L-ascorbyl-2-polyphosphate (LAPP). Two 10-week feeding experiments were carried out by using different size of fish (average body weight: (4.21±0.02) g in ExperimentⅠand (116.93±0.91) g in ExperimentⅡ). Each diet was fed to triplicate groups of fish to apparent satiation (experimentⅠ: three times a day, 6:00, 14:00 and 22:00; experimentⅡ: twice a day, 07:30 and 18:30), stocked with 60 (ExperimentⅠ) and 18 fish (ExperimentⅡ) respectively. During the experimentⅠ, water temperature ranges from 20 to 10℃, salinity from 24 to 26‰, pH from 7.8 to 8.0 and dissolved oxygen content was approximately 6mg/L. During the experimentⅡ, water temperature ranges from 24.1 to 18.8℃, salinity from 24 to 26‰, pH from 7.8 to 8.0 and dissolved oxygen content was approximately 6mg/L. The results showed that: ExperimentⅠ: Survival rate, specific growth rate and feed efficiency ratio showed an increasing tendency with increasing dietary vitamin C, but without significant (P>0.05) difference. Liver, kidney and muscle ascorbic acid concentration significantly increased with increasing dietary vitamin C (P<0.05). ExperimentⅡ: Survival rate and feed efficiency ratio increased with increasing dietary vitamin C, but not significantly (P>0.05). Specific growth rate wasn’t influenced significantly by dietary vitamin C. When supplemented more than 50mg/kg, liver, kidney, and muscle ascorbic acid concentrations significantly increased with increasing dietary vitamin C, all significantly higher than 0mg/kg diet group (P<0.05). We may conclude that, though dietary vitamin C benefits to survival to some extent, it is not nessesary to supply extra vitamin C in the basic diet of tonguefish (Cynoglossus semilaevis) under the experimental conditions.2. Six semi-purified diets were designed with 0, 100, 300, 900, 1800 and 3600 mg/kg choline chloride supplemented respectively to the basic diet to get six experimental diets with 260.2, 350.4, 531.5, 1020.9, 1914.3 and 3457.6mg/kg choline. A 10-week feeding experiment was carried out with flounder weighing (3.73±0.04) g. Each diet was fed to triplicate groups of fish to apparent satiation twice a day, 07:30 and 18:30), stocked with 20 fish each group. During the experiment, water temperature ranges from 16 to20℃, pH from 7.5 to 7.8, dissolved oxygen content was approximately 6mg/L and salinity was about 27‰. The results showed that: flounder fed the basal diet exhibited deficiency such as retarded growth, lower feed efficiency ratio and pale intestinal tract. Weight gain (WG) and feed efficiency ratio (FER) increased significantly (P<0.05) with increasing dietary choline, and survival rate (SR) showed increasing tendency without significant difference (P>0.05). WG levels off when dietary choline is more than 1914.3mg/kg. Hepatosomatic index (HSI) and visceral somatic index (VSI) of flounder decreased significantly with increasing dietary choline. (P<0.05). Moisture of flounder significantly decreased (P<0.05), whereas crude lipid increased (P<0.05). No significant differences were detected in liver lipid and muscle lipid, just showing increasing tendency, but cholesterol and triglyceride in plasma significantly increased as dietary choline increased. On the basis of WG (using broken-line modle), the optimum dietary choline requirement of juvenile flounder was estimated to be 1707.3mg/kg.3. Six semi-purified diets were designed with 0, 100, 300, 900, 1800 and 3600 mg/kg choline chloride supplemented respectively to the basic diet to get six experimental diets with 260.2, 350.4, 531.5, 1020.9, 1914.3 and 3457.6mg/kg choline. A 10-week feeding experiment was carried out with turbot weighing (6.25±0.04) g. Each diet was fed to triplicate groups of fish to apparent satiation twice a day, 07:30 and 18:30), stocked with 30fish each group. During the experiment, water temperature ranges from 16 to19℃, pH from 7.5 to 7.8, dissolved oxygen content was approximately 7mg/L and salinity was about 27‰. The results showed that: turbot fed the basal diet exhibited deficiency such as high death, retarded growth, lower feed efficiency ratio and pale intestinal tract. Weight gain (WG) and survival rate (SR) increased significantly (P<0.05) with increasing dietary choline, and feed efficiency ratio (FER) showed increasing tendency without significant difference (P>0.05). WG levels off when dietary choline was more than 1914.3mg/kg. Hepatosomatic index (HSI) wasn’t significantly affected, but visceral somatic index (VSI) of flounder decreased significantly with increasing dietary choline (P<0.05). Moisture and ash of flounder significantly decreased (P<0.05), whereas crude protein and crude lipid increased (P<0.05), crude lipid leveled off when dietary choline was more than 1914.3mg/kg. No significant difference was detected in muscle lipid, but liver lipid was (P<0.05), showing increasing then decreasing tendency. Cholesterol and triglyceride in plasma significantly increased as dietary choline increased. When dietary choline was above 1020.9mg/kg, triglyceride leveled off. On the basis of WG, crude lipid and triglyceride (using broken-line modle), the optimum dietary choline requirements of juvenile flounder were estimated to be 2089.8, 1800 and 951.6mg/kg. Practically considering, 2089.8mg/kg is recommend in turbot diet.更多还原