野生与人工养殖褐牙鲆亲鱼微量元素组成的差异比较

分析了野生与人工养殖褐牙鲆亲鱼肝脏、背肌及卵中硒、铁、锰、铜、铬、镉和铅等微量元素的含量。结果表明,野生褐牙鲆亲鱼肝脏中硒、铁含量均显著高于养殖亲鱼(P<0.05),铜含量则显著低于养殖亲鱼(P<0.05),其他各元素间均未见显著差异(P>0.05);野生褐牙鲆亲鱼背肌中除硒和锰的含量显著高于养殖亲鱼外(P<0.05),其他各元素含量均基本保持恒定(P>0.05);野生褐牙鲆亲鱼卵中硒、铁和锰的含量均显著高于养殖亲鱼(P<0.05),其中硒的含量约为养殖亲鱼的1.7倍,铁的含量约为养殖亲鱼的2.0倍,而锰含量则为养殖亲鱼的2.8倍。养殖褐牙鲆亲鱼卵中镉含量与野生亲鱼相比高出78%(P<0.05)。两种亲鱼卵中铜、镉、铅3种重金属含量均未见显著差异(P>0.05)。     

野生与人工养殖牙鲆亲鱼不同组织脂肪酸的比较

为研究脂肪酸对牙鲆繁育性能的影响, 采用生物化学方法, 对野生和养殖牙鲆亲鱼肌肉、肝脏及卵中脂肪酸组成分别进行测定。结果表明: (1) 牙鲆肌肉、肝脏和卵中脂肪含量大小关系为肝脏>卵>肌肉。野生亲鱼肌肉和卵中脂肪含量显著低于养殖亲鱼(P<0.05), 肝脏脂肪含量与养殖亲鱼无显著差异; (2) 牙鲆亲鱼3种组织中均检测出21种脂肪酸。野生亲鱼肌肉中饱和脂肪酸(SFA)与养殖亲鱼无显著差异, 单不饱和脂肪酸(MUFA)显著低于养殖亲鱼(P<0.05)。肝脏和卵中SFA显著高于养殖亲鱼(P<0.05), MUFA与养殖亲鱼无显著差异; (3) 野生亲鱼肌肉、肝脏和卵中高不饱和脂肪酸(PUFA)的含量, 尤其是肝脏和卵中C20:5n-3(EPA)、C22:6n-3(DHA)的含量均显著低于养殖亲鱼(P<0.05), 但肌肉和卵中的C20:4n-6(ARA)含量明显高于养殖亲鱼(P<0.05); (4) 野生牙鲆亲鱼肌肉、肝脏和卵中n-3/n-6 PUFA及EPA/ARA显著低于养殖亲鱼(P<0.05), 肝脏中DHA/EPA显著高于养殖亲鱼(P<0.05), 但野生亲鱼肌肉和卵中的DHA/EPA与养殖亲鱼无显著差异。比较结果说明, DHA、EPA和ARA等PUFA是与牙鲆繁殖性能密切相关的重要脂肪酸。在牙鲆亲鱼养殖过程中, 除了提供牙鲆亲鱼足够的脂肪酸营养外, 也应注意各种脂肪酸, 尤其是PUFA中各种脂肪酸之间的添加比例, 从而保证亲鱼的繁殖性能及卵和仔鱼的质量。     

野生和人工养殖褐牙鲆亲鱼不同组织氨基酸的比较

为了探明野生和人工养殖褐牙鲆亲鱼的繁育性能和卵巢发育之间的关系,采用生物化学方法,将处于Ⅲ~Ⅳ期和Ⅴ期的野生和养殖褐牙鲆亲鱼中肌肉、肝脏及卵巢氨基酸含量分别进行测定,结果表明,(1)褐牙鲆肌肉、肝脏、卵巢3种组织器官中总氨基酸含量大小关系为肌肉>卵巢>肝脏;(2) 发育同期的野生和养殖亲鱼肌肉中大部分氨基酸含量差异不显著（P>0.05）,并且随着性腺的成熟,野生和养殖亲鱼肌肉中大部分氨基酸较为稳定,其中含量变化显著的必需氨基酸为蛋氨酸、组氨酸（P<0.05）;(3) 发育同期的养殖亲鱼肝脏中大部分氨基酸含量高于野生亲鱼,随着性腺发育,野生和养殖亲鱼肝脏中氨基酸含量呈明显上升趋势;(4) 在Ⅴ期卵巢氨基酸组成中,除蛋氨酸、组氨酸含量存在显著差异外,野生和养殖亲鱼卵巢中氨基酸总量及必需氨基酸总量均不存在显著差异（P>0.05）,同时,随着性腺发育,野生和养殖亲鱼卵巢中氨基酸含量呈明显上升趋势,差异显著的必需氨基酸有精氨酸、蛋氨酸、组氨酸（P<0.05）。     

饲料中维生素C对大菱鲆繁殖性能的影响

在基础饲料中分别添加0、800和4 800mg/kg的维生素C饲养大菱鲆亲鱼240d,通过比较各处理组亲鱼的生长、性腺指数、相对产卵量、上浮卵率、孵化率、卵径以及各组织中超氧化物歧化酶（SOD）活性和丙二醛（MDA）含量,研究维生素C对大菱鲆亲鱼繁殖性能的影响。实验结果表明,各处理组亲鱼生长无显著差异（P>0.05）,但随着饲料中维生素C添加量的增加,亲鱼的生长呈上升趋势。800和4 800mg/kg组亲鱼相对产卵量显著高于对照组（P<0.05）。随着饲料中维生素C添加量的增加,亲鱼性腺指数、产卵次数、上浮卵率、受精率和孵化率均显著提高（P<0.05）,亲鱼卵和组织中维生素C含量反映了饲料中的维生素C含量。虽然各处理组亲鱼的卵径和油球径差异均不显著（P>0.05）,但随着饲料中维生素C添加量的增加,亲鱼卵径和油球径呈上升的趋势。肝脏、卵巢和血清中SOD活性随饲料中维生素C添加量的增加而显著升高（P<0.05）,而MDA含量则显著下降（P<0.05）。综上所述,大菱鲆亲鱼饲料中添加维生素C,能有效改善大菱鲆的繁殖性能。     

褐牙鲆(♀)×犬齿牙鲆(♂)杂交F1及其亲本肌肉营养成分分析与比较

褐牙鲆(Paralichthys olivaceus)为东亚地区重要的海水养殖鱼类,在中国、日本和韩国海水养殖业中占有重要的地位.目前,褐牙鲆经过连续多代缺乏选择的人工繁育和养殖,造成养殖群体种质发生退化,生长速度和抗逆性下降,极大制约了牙鲆养殖业发展.以选育生长迅速、抗逆性强、饵料转化率高的牙鲆类养殖新品种为目的,作者对褐牙鲆(♀)×犬齿牙鲆(Paralichthys dentatus)(♂)的杂交育种进行了研究.本实验对褐牙鲆(♀)×犬齿牙鲆(♂)杂交F1及其亲本肌肉营养成分进行测定.结果显示,杂交F1含水率显著低于双亲(P＜0.05),粗蛋白含量显著高于双亲(P＜0.05),粗脂肪含量介于二者之间;杂交F1的氨基酸总量、必需氨基酸、非必需氨基酸、半必需氨基酸与鲜味氨基酸总量都显著高于褐牙鲆与犬齿牙鲆(P＜0.05);脂肪酸含量方面,脂肪酸总量、不饱和脂肪酸总量3种鱼由高到低排列顺序为褐牙鲆、犬齿牙鲆、杂交F1,三者饱和脂肪酸总量差异不显著(P＜0.05).对3种鱼肌肉的营养品质进行了评价,杂交F1的必需氨基酸指数EAAI(90.30)明显高于褐牙鲆(77.75)与犬齿牙鲆(79.34),在蛋白质品质上表现出一定杂种优势.上述结果表明,杂交F1的肌肉具有蛋白和氨基酸含量较高、脂肪酸含量较低的特点.     

维生素C、E及高度不饱和脂肪酸交互作用对克氏原螯虾繁殖性能的影响

在室内,将体质量20~40g的克氏原螯虾饲养在50cm×40cm×40cm的水族箱中,投喂7种饲料:基础饲料(对照组,试验饲料1);基础饲料+0.5%维生素C+0.02%维生素E+8%高度不饱和脂肪酸(含6%秘鲁鱼油和2%大豆卵磷脂)(试验饲料2);基础饲料+0.5%维生素C+0.02%维生素E(试验饲料3);基础饲料+8%高度不饱和脂肪酸(试验饲料4);基础饲料+0.02%维生素E(试验饲料5);基础饲料+0.5%维生素C(试验饲料6);2#青虾全价颗粒饲料(粗蛋白≥30%)(试验饲料7),每组饲料设置3个重复,研究了在饲料中添加维生素C、E及高度不饱和脂肪酸对克氏原螯虾培育成活率、抱卵率、抱卵量及孵化率的影响。76d的繁育结果表明,7组试验饲料对克氏原螯虾亲虾的培育成活率影响不显著(P0.05)。试验饲料2组亲虾的抱卵率(75%)和孵化率(82.8%)最高,显著高于对照组(P0.05)。饲料2组、3组、5组、6组亲虾的相对抱卵量差异不明显(P0.05),显著高于饲料4组(仅添加高度不饱和脂肪酸)、1组(P0.05),添加维生素C、维生素E的饲料3组的亲虾相对抱卵量最高,亲虾平均抱卵18粒/g,仅添加高度不饱和脂肪酸的饲料4组,亲虾培育成活率及相对抱卵量较低。结果表明,维生素C、维生素E和高度不饱和脂肪酸具有交互作用,能提高克氏原螯虾的繁殖性能。     

饲料中添加不同水平的维生素E对半滑舌鳎(Cynoglossus semilaevis)亲鱼繁殖性能及后代质量的影响

在饲料中分别添加0、200、1200 mg/kg的维生素E(DL-α-生育酚乙酸脂形式)配制成Ec、El和Eh三种试验饲料,饲喂3龄半滑舌鳎亲鱼(雌性1.58±0.19 kg/尾、雄性0.20±0.05 kg/尾)70 d,探讨饲料中添加不同水平的维生素E对半滑舌鳎亲鱼繁殖性能的影响。结果显示,饲料中添加1200 mg/kg的维生素E(Eh组)不仅可以促进亲鱼性腺的发育,提高亲鱼产卵量、浮卵率、受精率、孵化率以及初孵仔鱼长度,而且影响仔鱼质量,仔鱼的成活率、12 d仔鱼长度、生存活力等方面均要高于对照组。而饲料中添加200 mg/kg的维生素E(El组)只对亲鱼性腺的发育和初孵仔鱼长度有一定的促进作用,对亲鱼产卵量、浮卵率、受精率、孵化率没有显著影响(P>0.05)。随饲料中维生素E的增加,血清中SOD的活性显著升高(P<0.05),MDA含量则显著下降(P<0.05)。此外,El和Eh试验组卵中干物质、维生素C的含量,以及卵子脂肪酸中PUFA、n-3PUFA、n-3HUFA和n-6PUFA的含量均要高于Ec组,El和Eh试验组之间的没有显著性差异(P>0.05)。结果表明,在半滑舌鳎亲鱼饲料中添加适量维生素E会亲鱼促进性腺的发育,增加产卵量,提高卵子和仔鱼的质量。在本试验中Eh组(1200 mg/kg)亲鱼的繁殖性能要优于Ec组(0 mg/kg)和El组(200 mg/kg)。     

不同钙、镁浓度对褐牙鲆幼鱼生长及SOD和CAT酶活力的影响

在盐度30和水温20℃条件下,配制钙、镁(1∶3)总浓度A(700mg/L)、B(1100mg/L)、C(1600mg/L,对照)、D(2200mg/L)、E(2800mg/L)的人工海水,研究了5种人工海水对褐牙鲆Paralichthys olivaceus幼鱼生长、肝脏超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活力的影响。观察发现,褐牙鲆幼鱼初次接触高钙、镁浓度人工海水(D组和E组)时产生应激反应,鱼体呈弓形,呼吸频率降低,摄食不积极,适应7d左右恢复正常。经60d养殖实验,各处理组实验鱼食物转化效率(FCE)无显著差异(P0.05),成活率均在90%以上。0~20d时实验鱼特定生长率(SGR)和摄食率(FI)差异显著(P0.05),低浓度组大于高浓度组,20d后,FI无显著差异(P0.05),40~60d时低浓度组SGR小于高浓度组。各处理组SGR和FI随钙、镁总浓度上升呈下降趋势,实验进行到60d时,低浓度组A的SGR和FI分别为高浓度组E的1.13倍和1.04倍。不同钙、镁浓度对实验鱼的免疫酶活性亦有显著影响。D组实验鱼SOD酶活力和肝比重显著高于其他各处理组;E组SOD酶活力显著低于其他实验组(P0.05),CAT酶活力也低于其他处理组,但各组间差异不显著(P0.05)。研究结果表明,实验初期钙、镁浓度通过影响褐牙鲆的摄食而影响其生长,低钙、镁浓度组实验鱼生长较快,高浓度组生长较慢。经60d养殖驯化,除E组外的各处理组特定生长率差异不显著,过高浓度钙、镁对褐牙鲆的免疫酶活性产生一定抑制作用。建议养殖褐牙鲆时应注意避免水体钙、镁含量过高。     

脊尾白虾自然群体与养殖群体的营养差异

对脊尾白虾的自然群体和养殖群体肌肉组织中的水分、灰分、蛋白质、脂肪含量及脂肪酸的组成进行了分析比较.结果表明,养殖白虾肌肉中的水分含量高于自然海区白虾,差异非常显著(P<0.01),分别为80.86%和79.02%,水分含量平均值为79.94%;养殖白虾肌肉中的蛋白质含量低于自然海区白虾,差异非常显著(P<0.01),分别为17.29%和19.02%,蛋白质含量平均值为18.16%;两者的灰分含量差异非常显著(P<0.01),分别为1.44%和1.39%;脂肪含量野生白虾也显著高于养殖白虾(P<0.01),分别为0.55%和0.30%;脊尾白虾含有大量的饱和及不饱和脂肪酸(C<,14-22>),饱和脂肪酸以棕榈酸为主,占总脂肪酸的15%以上,不饱和脂肪酸含量高达75%左右,其中多不饱和脂肪酸的比例非常高,养殖白虾和野生白虾分别为44.07%和46.21%,长链多不饱和脂肪酸中以EPA和DHA为主,EPA DHA含量的含量超过总脂肪酸的30%,无论是野生脊尾白虾还是养殖脊尾白虾都具有很高的营养价值,但养殖虾肉和野生虾肉相比,营养成分有较大的差异.     

小黄鱼亲鱼培育和催产技术的初步试验

2014—2015年对野生小黄鱼在人工养殖条件下的繁育技术进行了相关试验研究,主要包括亲鱼的室内越冬、强化培育和人工催产技术。选取2000尾小黄鱼,体质量平均为67.24g,分别饲养于4m×8m×1.5m的越冬池,越冬池水温10~11℃,投喂少量配合饲料,进行亲鱼营养强化,亲鱼使用促黄体素释放激素A2和人绒毛膜促性腺激素催产。经52d营养强化,小黄鱼体质量增至88.30g,营养强化组的卵巢质量和性腺指数均显著高于对照组(P0.05),表明通过投喂冰鲜饵料并添加维生素C和维生素E,可显著促进小黄鱼的性腺发育和成熟,提高其性腺指数和相对怀卵量;使用1.2μg/kg促黄体素释放激素A2搭配500IU/kg人绒毛膜促性腺激素对雌鱼进行催产,催产效果最佳,人工受精率和孵化率分别为23.35%和80.56%。     

Egg quality determinants in cod (Gadus morhua L.): egg performance and lipids in eggs from farmed and wild broodstock

Lipids and essential fatty acids, particularly the highly unsaturated fatty acids, 20:5n‐3 (eicosapentaenoic acid; EPA), 22:6n‐3 (docosahexaenoic acid; DHA) and 20:4n‐6 (arachidonic acid, AA) have been shown to be crucial determinants of marine fish reproduction directly affecting fecundity, egg quality, hatching success, larval malformation and pigmentation. In Atlantic cod (Gadus morhua L.) culture, eggs from farmed broodstock can have much lower fertilization and hatching rates than eggs from wild broodstock. The present study aimed to test the hypothesis that potential quality and performance differences between eggs from different cod broodstock would be reflected in differences in lipid and fatty acid composition. Thus eggs were obtained from three broodstock, farmed, wild/fed and wild/unfed, and lipid content, lipid class composition, fatty acid composition and pigment content were determined and related to performance parameters including fertilization rate, symmetry of cell division and survival to hatching. Eggs from farmed broodstock showed significantly lower fertilization rates, cell symmetry and survival to hatching rates than eggs from wild broodstock. There were no differences in total lipid content or the proportions of the major lipid classes between eggs from the different broodstock. However, eggs from farmed broodstock were characterized by having significantly lower levels of some quantitatively minor phospholipid classes, particularly phosphatidylinositol. There were no differences between eggs from farmed and wild broodstock in the proportions of saturated, monounsaturated and total polyunsaturated fatty acids. The DHA content was also similar. However, eggs from farmed broodstock had significantly lower levels of AA, and consequently significantly higher EPA/AA ratios than eggs from wild broodstock. Total pigment and astaxanthin levels were significantly higher in eggs from wild broodstock. Therefore, the levels of AA and phosphatidylinositol, the predominant AA‐containing lipid class, and egg pigment content were positively related to egg quality or performance parameters such as fertilization and hatching success rates, and cell symmetry.     

Dietary vitamin C and E supplementation and reproduction of milkfish Chanos chanos Forsskal

Milkfish Chanos chanos Forsskal broodstock (11 years old, average body weight 5.23–5.73 kg) reared in 10‐m‐diameter by 3‐m‐deep floating net cages (31–36 fish per cage) at SEAFDEC AQD's Igang Marine Substation in Guimaras Island, central Philippines, were fed daily at 3% of total body weight formulated diets (36% protein, 7–8% lipid) supplemented with 0.1% vitamin C, 0.05% vitamin E, both vitamin C and E or no vitamin supplementation (control) for 3 years. Reproductive performance was assessed in an attempt to determine the optimum nutrition for successful spawning of milkfish. The total egg production, mean number of eggs per spawning, number of spawns and mean egg diameter were not affected by dietary vitamin C and E supplementation. However, broodstock given dietary supplementation of vitamin C alone or in combination with vitamin E had a higher percentage of spawns with higher (> 90%) percentage egg viability, hatching and cumulative survival rate than those of the control. Broodstock given dietary vitamin E supplementation alone had few spawns, which made the results difficult to analyse. The results confirm the essentiality of vitamin C supplementation in producing more spawns with good egg and larval quality. The production of an adequate volume of good quality eggs and larvae to support hatchery operation is necessary to offset the huge investment in broodstock development, as it takes at least 5 years for milkfish to attain sexual maturation and spawning.     

养殖和野生亚东鲑机体成分比较分析

亚东鲑(Salmo trutta fario)是鲑属鱼类在青藏高原仅有的鱼类种群,是亚东地区全国农产品地理标志产品。本研究对西藏亚东地区野生和养殖亚东鲑的常规营养成分及各组织氨基酸和脂肪酸组成进行分析,旨在比较野生和养殖亚东鲑营养成分的异同,为养殖亚东鲑的品质评价和饲料配方的完善提供参考信息。实验采集亚东河中野生亚东鲑和亚东渔业产业园中使用配合饲料养殖的亚东鲑各10尾用于相关成分分析,每尾为一个独立样本。结果显示,野生组肥满度显著低于养殖组,而全鱼水分和灰分显著高于养殖组。全鱼粗蛋白、粗脂肪以及肝脏常规成分在野生组和养殖组间无显著差异。野生组肌肉粗脂肪显著低于养殖组,而水分含量显著高于养殖组。野生组全鱼必需氨基酸总量显著高于养殖组,且野生组肌肉中苏氨酸、缬氨酸、苯丙氨酸、赖氨酸和甘氨酸含量显著高于养殖组。野生组全鱼、肌肉和肝脏中饱和脂肪酸、n-3多不饱和脂肪酸(n-3 PUFA)总量、EPA、C20:4n-6以及肌肉中DHA含量高于养殖组,而全鱼和组织中单不饱和脂肪酸和n-6 PUFA总量低于养殖组。综上所述,目前养殖亚东鲑和野生亚东鲑在机体成分上存在较大差异。由于养殖鱼类体成分很大程度上反映了饲料组成,因此,亚东鲑养殖中饲料营养组成可能有待进一步优化。     

维生素E、C和HUFA交互作用对中华绒螯蟹生殖性能的影响

通过投喂添加或不添加VE、VC和HUFA的四组实验饲料,经198d饲养实验,以雌蟹的性腺系数、产卵力、孵化率、各组织超氧化物歧化酶(SOD)活性和过氧化产物丙二醛(MDA)含量等为指标,研究这两类营养素交互作用对其生殖性能的影响。结果表明,VE、VC和HUFA对雌蟹生殖性能有显著的影响(P<0.05):在产卵力方面,1组为3790个卵细胞·g-1体重,极显著高于2组(为2317个卵细胞·g-1体重)和3组(为2129个卵细胞·g-1体重)(P<0.01),显著高于4组(为3050个卵细胞·g-1体重)和5组(对照组)(为3010个卵细胞·g-1体重)(P<0.05);而孵化率方面,1组(86.17%)极显著高于2组(36.06%)、3组(29.18%)和4组(25.73%)(P<0.01),也显著高于5组(71.12%)(P<0.05)。1组和2组雌蟹性腺中SOD活性分别为40.09Nu·mL-1和39.87Nu·mL-1,相应地,MDA含量分别为6.87nmol·mL-1和3.33nmol·mL-1;而3组和4组雌蟹,尽管其性腺中SOD活性较高,分别为79.21Nu·mL-1和85.2Nu·mL-1,但由于饲料中抗氧化性VE、VC的缺乏,导致脂质过氧化发生,其MDA含量显著增加(P<0.05),分别为12.65nmol·mL-1和25.18nmol·mL-1。4组雌蟹的产卵力较大,但因VE、VC的缺乏发生脂质过氧化,导致所产的卵质低下,从而影响了卵子的孵化率。结果表明,VE、VC和HUFA都是河蟹保持良好的生殖性能的必需营     

The effect of vitamin A supplementation in broodstock feed on reproductive performance and larval quality in Penaeus chinensis

The effect of feeding four semi‐purified diets A1, A2, A3, A4, containing different vitamin A acetate levels 0, 20, 40, 60 mg kg^?1 diet, respectively, on fecundity, egg hatching rate, larval survival rate and vitamin A content in eggs of Chinese shrimp (Penaeus chinensis) broodstock was compared with a fresh clam diet (control) in a 60‐day feeding trial. The broodstock shrimp fed the diet with 60 mg kg^?1 vitamin A acetate added exhibited significantly higher fecundity (P < 0.01). Hatching rate was highest with diet A4 (P < 0.05), whereas hatching rates were similar fed diets A1, A2, A3. Increasing levels of vitamin A in broodstock diet resulted in improvement in larval quality. The vitamin A levels in shrimp eggs from broodstock fed with diet A4 were higher compared with those from broodstock fed with diet A1, A2 (P < 0.01). The fecundity and hatching percentages were positively correlated with the vitamin A content in eggs in the present study. The results of this study showed that higher level of vitamin A in broodstock diet may have positive effects on fecundity and larval quality in P. chinensis.     

Effects of high dose of vitamin A on reproduction and egg quality of Japanese flounder Paralichthys olivaceus

ABSTRACT: The present study was conducted to investigate the effects of dietary vitamin A on reproduction and egg quality in Japanese flounder Paralichthys olivaceus . Broodstock were fed experimental pellets containing two levels of vitamin A [11 × 10³ IU/100 g (control diet; CD), 337 × 10³ IU/100 g (experimental diet; ED)] for approximately 2 months before spawning and during the spawning period. Two groups of five females (average weight 1.4 kg) and 10 males (average weight 0.7 kg) were randomly allocated to two 30 m³ indoor tanks. Total egg production of the CD group was slightly higher than the ED group. Percentage of buoyant eggs and hatching rate of the ED group were significantly higher than the CD. In other egg quality parameters, such as percentage abnormal larvae and starvation tolerance of larvae, no notable difference was found between these two groups. At the end of the experiment, the skin color of broodstock in the ED group was darker than that of the CD group. Vitamin A content in eggs of the ED group was significantly higher than that of the CD group. However, the difference in vitamin A content in eggs between the ED and CD groups was much smaller than that in the liver of the females between the two groups. These results indicate that feeding broodstock a higher level of vitamin A increases the vitamin A content in eggs but does not affect egg quality in Japanese flounder because excess dietary vitamin A was stored mainly in the broodstocks' liver.     

A comparison of fatty acid composition and quality aspects of eggs and larvae from cultured and wild broodstock of common sole (Solea solea L.)

Eggs from a F₁ cultured broodstock of sole were compared with eggs from wild‐caught breeders throughout one spawning season, to evaluate if egg quality may be affected by culture‐related conditions. Fourteen batches of eggs from cultured broodstock and 17 batches from wild‐caught sole were compared with respect to fatty acid (FA) composition, egg size, fertilization rate and hatching rate. Based on a multivariate analysis of the FA profiles, it was possible to discriminate between culture and wild inheritance. Eggs from cultured broodstock had high levels of C20:1(n‐9), C18:2(n‐6) and C18:3(n‐3), whereas eggs from wild fish had high levels of C16:1(n‐7), C20:4(n‐6) and C20:5(n‐3). Differences in FA profiles were most likely related to dietary differences. Fertilization and hatching rates were generally low and lowest in eggs from cultured broodstock, but not related to FA composition. Larval growth of one batch from each group was compared. Larval growth was not correlated to broodstock origin, FA composition or egg or larval size. However, larval survival was significantly lower for larvae from cultured broodstock.     

The fatty acid compositions of total,neutral and polar lipids in wild and farmed lambari (Astyanax altiparanae) (Garutti & Britski, 2000) broodstock

One way to develop broodstock fish diets is to determine the compositions of wild broodstock tissues and attempt to replicate these compositions in the eggs of farmed fish via dietary manipulation. We collected 30 wild and 30 farmed lambari females that were in the reproductive stage. The extraction and separation of polar and neutral fractions and the saponification and methylation of lipids were performed and analysed in the muscles, livers and ovaries to determine the compositions of the fatty acids via gas chromatography. Regardless of habitat, lambaris mobilize large amounts of fat to the ovaries during the reproductive period, in addition to highly unsaturated fatty acids, such as arachidonic, eicosapentaenoic and docosahexaenoic acids. The wild lambaris were observed to contain higher levels of various fatty acids, including linoleic acid, which is an essential fatty acid. The most abundant fatty acid that was observed in the commercial diet was linoleic acid, which was supplied in all fish farmed tissues. The commercial diet has low AA, EPA and DHA contents, and, higher levels of these fatty acids were recorded in the tissues of farmed lambari, which suggests that this species are able to elongate and desaturate precursors, linoleic and linolenic acids, into highly unsaturated fatty acids.