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     

三种投喂模式对河蟹二龄成蟹养殖性能的影响

比较了池塘养殖条件下,全程投喂配合饲料、杂鱼和传统饵料(以黄豆、小麦和玉米为主,辅以少量饲料和杂鱼)对河蟹(Eriocheir sinensis)二龄成蟹生长、性腺发育、规格分布、成活率、单产、饵料系数和饵料成本的影响。结果显示:(1)无论雌雄,传统饵料组早期(5-8月份)的增重率和特定生长率方面最低,杂鱼组最高;(2)杂鱼组雌体8月份性腺发育速度最快,传统饵料组性腺发育速度最慢,其余月份雌体和雄体的性腺指数和肝胰腺指数均无显著差异;(3)无论雌雄,最终杂鱼组的大规格成蟹(雄体175 g,雌体100 g)比例最高,而传统饵料组的小规格成蟹(雄体100 g,雌体75 g)比例最高,且体重差异较大,配合饲料组的中等规格成蟹较为集中,最终三组投喂模式下雌雄蟹的平均体重并无显著差异,杂鱼组略大于传统饵料组;(4)三种投喂模式下,三者的成活率和平均产量并无显著差异;杂鱼组的饵料系数和饵料成本最高,配合饲料组饵料系数最低,但饵料成本居中;传统饵料组饵料系数居中,饵料成本最低。结果表明,全程投喂配合饲料对河蟹二龄成蟹的养殖性能和性腺发育无显著影响。     

维生素E对克氏原螯虾生殖的影响

实验用不同的维生素E(VE)含量的饲料投喂克氏原螯虾亲虾,研究对其繁殖性能的影响,目的是为研制亲虾的人工饲料提供指导.结果显示,在添加VE量分别为基础饲料干重的0%、0.004%、0.02%、0.1%和0.5%的5个饲料组中,0.02%VE组不仅可以增加产卵雌虾的数量比例,而且也能提高克氏原螯虾雌虾的产卵量.随着VE含量的升高,产卵雌虾的比例呈下降趋势,单个雌虾的产卵量与0.02%VE组差不多,这表明饲料中适当添加VE可促进克氏原螯虾产卵,但饲料中VE含量过高对克氏原螯虾的繁殖产生负面影响.在饲料中添加适量的VE能够提高亲虾繁殖能力,方法简单,效果明显,适合规模化生产的需要,可以推广.     

维生素A、E对凡纳滨对虾受精率、孵化率及幼体存活率的影响

通过对凡纳滨对虾Litopenaeusvannamei雌虾投喂添加或不添加维生素A(VA)、维生素E(VE)的4组实验饲料,并以饲喂活饵组为对照组,研究了维生素A、E对凡纳滨对虾受精率、孵化率和幼体存活率的影响.结果表明,第1(饲料中添加0.002%VE)、2(饲料中添加0.002%VE,0.004%VA)、3组(饲料中添加0.004%VA)凡纳滨对虾的受精率、孵化率、幼体存活率及仔虾应激实验(仔虾入淡水30min,再入海水30min)后的存活率均显著高于第4组(饲料中未添加VA、VE),而且第2组凡纳滨对虾的受精率、孵化率及幼体存活率(Z1-M2)与第1、3组相比有增高的趋势.     

维生素E对克氏原螫虾生殖的影响

实验用不同的维生素E（VE）含量的饲料投喂克氏原螯虾亲虾，研究对其繁殖性能的影响，目的是为研制亲虾的人工饲料提供指导。结果显示，在添加VE量分别为基础饲料干重的0％、0．004％、0．02％、0．1％和0．5％的5个饲料组中，0．02％VE组不仅可以增加产卵雌虾的数量比例，而且也能提高克氏原螯虾雌虾的产卵量。随着VE含量的升高，产卵雌虾的比例呈下降趋势，单个雌虾的产卵量与0．02％VE组差不多，这表明饲料中适当添加VE可促进克氏原螯虾产卵，但饲料中VE含量过高对克氏原螯虾的繁殖产生负面影响。在饲料节添加适量的VE能够提高亲虾繁殖能力，方法简单，效果明显，适合规模化生产的需要，可以推广。     

不同脂肪源饲料对中华绒螯蟹卵巢发育与繁殖性能的影响

在基础饲料(CP 40%)中分别添加6%的鱼油、花生油、卵磷脂和猪油,投喂中华绒螯蟹(Eriocheir sinensis,简称河蟹)28周,以投喂冰鲜小杂鱼的河蟹为对照组,研究投喂不同脂肪源饲料对河蟹卵巢发育和繁殖性能的影响。结果表明,饲料脂肪源对河蟹的卵巢发育和繁殖性能影响显著,鱼油组雌蟹的产卵力[2.787×103cell/g(Wt)]显著高于其他实验组,卵磷脂组[2.216×103cell/g(Wt)]和对照组[2.041×103cell/g(Wt)]次之;而鱼油、卵磷脂和对照组间雌蟹的受精率与孵化率无显著差异,但均显著高于猪油和花生油组;猪油组雌蟹的繁殖性能最差,其产卵力与孵化率分别仅为鱼油组的56.9%和32.57%,受精率也较鱼油组显著降低;随着饲养时间的延续,对照组河蟹肝体指数(HSI)逐渐下降,而性腺指数(GSI)持续上升,Ⅲ1～Ⅲ2期增幅最大,Ⅲ2期雌蟹GSI值高达9.15,显著高于同期其他实验组,且同期血淋巴中卵黄蛋白原(Vg)的含量显著升高。与对照组不同,各饲料组卵巢发育期的物质积累峰值主要发生在Ⅲ2～Ⅳ期,GSI峰值均出现在性腺发育的第Ⅳ期,磷脂组与鱼油组Ⅳ期的GSI最高,分别为11.50和11.25,花生油组次之(8.85),猪油组最低(7.30);猪油能明显提高河蟹性腺发育早期血淋巴中Vg的含量,但当性腺成熟至Ⅳ期时,除卵磷脂组外,其他饲料组血淋巴Vg含量较Ⅲ2期显著降低,且猪油组和对照组血淋巴中Vg含量显著低于其他饲料组。结果表明,Ⅲ1～Ⅲ2期是河蟹雌体肝胰腺营养物质向卵巢转移,卵巢营养物质快速积累的时期,且饲料脂肪源可通过影响卵巢中卵黄蛋白源等营养物质的合成和积累,进而影响到河蟹卵巢发育和繁殖性能。综合比较,卵磷脂也可以作为河蟹雌性亲体的优质饲料脂肪源。     

虾青素对红白锦鲤体色、生长的影响

为研究虾青素对锦鲤体色、生长的影响,在基础饲料中添加不同量的虾青素对红白锦鲤幼鱼进行了饲喂试验。试验鱼的初始体质量为7.31±0.12 g,饲料中虾青素的添加量分别为0、100、400、700、1 000、1 300、1 600 mg·kg-1,表观饱食投喂60 d。结果表明:随着虾青素添加量的增加,锦鲤皮肤和背鳍中的类胡萝卜素含量逐渐升高,700 mg·kg-1组的类胡萝卜素显著高于添加量为0的对照组,最高值出现在1 600 mg·kg-1组,但1 600 mg·kg-1组背鳍中的类胡萝卜素含量与1 000、1 300 mg·kg-1组间差异不显著;在促生长方面,100、700 mg·kg-1组的体质量增长率(BWG)、蛋白质效率(PER)显著高于对照组,虾青素添加量对锦鲤的肥满度(CF)、肝体指数(HSI)、脏体指数(VSI)无显著影响。研究结果说明,在饲料中添加虾青素可有效改变锦鲤的体色。综合考虑经济效益,饲料中虾青素的适宜添加量为700 mg·kg-1。     

2种饵料模式对稻田养殖中华绒螯蟹幼蟹养殖性能和生理代谢的影响

为优化稻田养殖中华绒螯蟹(Eriocheir sinensis)幼蟹的饵料模式,本研究分别采用配合饲料和传统饵料(豆粕、麸皮、玉米和小麦)投喂稻田养殖中华绒螯蟹幼蟹152 d,每种投喂组各3个重复,比较2种饵料模式对幼蟹养殖性能、蛋白质代谢、消化酶、抗氧化和免疫指标的影响。结果显示,配合饲料组的雌蟹和雄蟹体质量均高于传统饵料组,但差异不显著(P>0.05);就养殖性能而言,2种饵料模式下,配合饲料组正常幼蟹的平均体质量及产量、1龄早熟蟹平均体质量及其产量、总产量和成活率均略高于传统饵料组,饵料系数显著低于传统饵料组(P<0.05);就蛋白质代谢而言,配合饲料组雌蟹和雄蟹血淋巴中的总蛋白含量显著高于传统饵料组(P<0.05),而传统饵料组雄蟹血淋巴中的尿素氮含量和肝胰腺中的谷草转氨酶活力显著高于配合饲料组(P<0.05);配合饲料组雌蟹和雄蟹肝胰腺中的脂肪酶均显著高于传统饵料组(P<0.05),而雄蟹的α-淀粉酶活力显著低于传统饵料组;配合饲料组的雌蟹血淋巴中总抗氧化能力、碱性磷酸酶、酸性磷酸酶活力和肝胰腺中酸性磷酸酶活力均显著高于传统饵料组(P<0.05)。综上所述,投喂配合饲料可以提高稻田扣蟹的养殖性能、促进蛋白质沉积和脂类吸收、增强幼蟹抗氧化和免疫能力、提高蟹种质量。     

不同饵料投喂模式对中华绒螯蟹幼蟹生长和生理生化的影响

为研究池塘养殖过程中不同饵料投喂模式对中华绒螯蟹(Eriocheir sinensis)幼蟹生长和生理生化的影响, 实验以中华绒螯蟹幼蟹为研究对象, 比较了喜旱莲子草(Alternanthera philoxeroides)组(Diet1 组)、配合饲料组(Diet2 组)以及两者 1 1 ∶ 混合组(Diet3 组) 3 种饵料投喂模式下幼蟹生长、消化酶、抗氧化酶及免疫酶活性的变化。每个处理组设置 3 个重复, 实验周期为 120 d。结果表明: (1)养殖结束时, Diet2 组幼蟹的终末体重、增重率、特定生长率和肝胰腺指数均显著高于 Diet1 和 Diet3 组; (2) Diet2 和 Diet3 组幼蟹肝胰腺和躯体的粗脂肪含量显著高于 Diet1 组, 而灰分含量呈相反趋势; (3)幼蟹肝胰腺 α-淀粉酶活性在 Diet3 组最高(P<0.05), 而脂肪酶活性在 Diet2 组最高 (P<0.05); (4) Diet1 组幼蟹血清过氧化氢酶活性最高, 而 Diet2 组和 Diet3 组总抗氧化能力和丙二醛含量均显著高于 Diet1 组; (5) Diet1 组幼蟹肝胰腺过氧化氢酶酶活性最高, Diet2 组雌蟹超氧化歧化酶活性和总抗氧化能力活性最高 (P<0.05), Diet3 组雄蟹总抗氧化能力活性最高(P<0.05); (6) Diet2 组和 Diet3 组幼蟹血清中酸性磷酸酶和碱性磷酸酶活性均显著高于 Diet1 组, 而在雌雄蟹肝胰腺中, 三组间酸性磷酸酶和碱性磷酸酶活力不存在显著差异(P>0.05)。 因此, 在中华绒螯蟹池塘养殖模式下, 在合理的种植水花生的基础上投喂配合饲料有利于幼蟹生长、消化和脂肪积累, 以及增强幼蟹抗氧化和免疫能力。本研究可为配合饲料投喂模式的推广以及将水花生作为植食性饵料添加到中华绒螯蟹幼蟹配合饲料中的开发提供科学参考与理论基础。     

全程投喂配合饲料条件下池养中华绒螯蟹的生长性能及其性腺发育

于2012年5月至2013年11月,对池养中华绒螯蟹(Eriocheir sinensis)全程投喂配合饲料,观测扣蟹和成蟹阶段的生长规律、成活率、早熟率、性腺发育速度、产量、规格分布和饲料系数等。结果表明:(1)扣蟹阶段雌雄生长差异不显著(P0.05),增重率(WG)和特定增长率(SGR)为先上升后下降,整个扣蟹培育阶段的平均SGR为1.9%/d左右;平均成活率和早熟率分别为10.0%和4.9%,雌体的早熟率显著高于雄体(P0.05);一龄早熟蟹和正常扣蟹的平均体重分别为19.8 g和7.5 g左右,一龄早熟蟹和正常扣蟹的平均产量分别为229 kg/hm~2和2433 kg/hm~2;扣蟹培育阶段饲料投喂主要发生在7—10月,占全部饲料用量的80%以上,饲料投喂量与扣蟹体重及池塘水温具有一定的关系,扣蟹阶段饲料系数(FCR)为2.15。(2)成蟹养殖过程中,自6月份起雄体体重大于雌体,整个养殖阶段雄体的SGR显著高于雌体(P0.05);雌雄成蟹最终平均体重分别为126.1 g和181.1 g,雌、雄及总体成活率分别为61.30%、53.47%和58.4%,产量分别为412.20 kg/hm~2、536.10 kg/hm~2和950 kg/hm~2;成蟹养殖的饲料消耗主要发生在7—10月,其中育肥前期(9—11月)的饲料用量占50%左右,整个成蟹养殖阶段的FCR为2.63。(3)池养成蟹的生殖蜕壳主要发生在8—9月,雌体比雄体早20 d左右;雌体的性腺发育主要发生在生殖蜕壳后的9—10月,雄体的性腺发育时间跨度较长,生殖蜕壳前性腺指数已达0.8%左右;雌雄成蟹性腺发育期间肝胰腺指数均呈下降趋势。综上,全程投喂配合饲料能保证池养中华绒螯蟹的正常生长发育,可大规模推广应用于中华绒螯蟹养殖产业。     

Changes in the growth performance,antioxidant enzymes and stress resistance caused by dietary administration of synbiotic (fructooligosaccharide and probiotics) in juvenile Chinese Mitten Crab,Eriocheir sinensis

The research aimed to evaluate the effects of dietary fructooligosaccharide, probiotics and their combination on the growth performance, antioxidant enzymes and stress resistance of juvenile Eriocheir sinensis. Crabs (average weight: 9.90?±?0.07 g) were randomly assigned into 4 groups (3 tanks per group) fed experimental diets: basal diet (control group), basal diet supplemented with 5 g/kg FOS, basal diet supplemented with 2 g/kg multi-strain probiotics (each gram contains Lactobacillus acidophilus 10⁶ CFU?+?Bacillus subtilis 10⁷ CFU?+?Saccharomyces cerevisiae 10¹⁰ CFU) and basal diet supplemented with symbiotic (5 g/kg FOS?+?2 g/kg multi-strain probiotics) (designated as control, D1, D2 and D3, respectively). After 8 weeks of feeding trial, crabs were exposed to the transportation process (3 h). Cumulative mortality was recorded at 24 h, 48 h, 72 h and 96 h after transport stress, and pre-transport and post-transport sampling of hepatopancreas occurred for assay. The results indicated that crabs fed D3 had significantly higher weight gain (WG), specific growth rate (SGR) and lower feed conversion ratio (FCR) than crabs fed control diet. Before stress, compared to the control group, crabs fed D1 and D3 diet significantly increased catalase (CAT), superoxide dismutase (SOD) activities and decreased malondialdehyde (MDA) activities, the highest activities of pepsin, trypsin and chymotrypsin were observed in crabs fed D2 diet. After stress, there was a trend that the activities of antioxidants enzymes and proteases in all groups were significantly decreased. And compared to the control group, crabs fed D1 and D3 diet significantly improved SOD and CAT activities, the lowest MDA activity was observed in crabs fed D3 diet, no significant difference was obtained in activities of total antioxidant capacity (T-AOC) and three proteases among all groups (P?>?0.05). At 96 h after transportation process, the lowest cumulative mortality was observed in crabs fed D3 diet, the difference among all groups before and at 24 h, 48 h and 72 h after stress was not significant (P?>?0.05). In summary, a basal diet supplemented with synbiotic could improve the growth performance and protect the hepatopancreas of Eriocheir sinensis more effectively than singular supplementation with prebiotics or probiotics.

     

Reproductive performance and offspring quality of Chinese mitten crab Eriocheir sinensis (H. Milne-Edwards) females fed an optimized formulated diet and the razor clam Sinonovacula constricta

After feeding female Eriocheir sinensis on an optimized formulated diet or fresh razor clam Sinonovacula constricta for 7 months, their reproductive performance and offspring quality were compared. To evaluate diet nutrient contents, the proximate, fatty acid and amino acid compositions of the formulated diet and the razor clam were analysed. The nutritional value of the diets was determined by assessing survival, gonadosomatic index (GSI) and hepatosomatic index (HSI) of female crabs from both diet treatments, together with the percentage of females that spawned, total egg production per female and fecundity (number of eggs g^?1 female wet weight). Furthermore, the quality of eggs and newly hatched larvae from the two dietary treatments were determined using the following parameters: egg diameter, wet weight and dry weight, hatchability, proximate and fatty acid profile of eggs, larval carapace length, resistant to starvation and osmotic shock, larval survival and development to the zoea II stage. Higher protein, phospholipids (PL) and amino acids (AA) contents were found in the razor clam while the formulated diet contains higher levels of ash, total lipid (TL) and 18:1n‐9, 18:2n‐6 and 22:6n‐3 fatty acids. Although female crabs fed the two different diets showed similar reproductive performances, newly hatched zoea I larvae produced by the crabs fed the formulated diet had significantly longer mean carapace length and shorter development time to the zoea II stage under identical culture condition (P<0.05). Moreover, dietary fatty acid appeared to have more significant effects on the fatty acid composition of the hepatopancreas than it did on mature ovaries or eggs. This suggests that the fatty acid profile of mature ovaries is indicative of the specific fatty acid required for ovarian development in E. sinensis. In conclusion, our results show that the optimized formulated diet developed in this laboratory can totally replace the razor clam, a broodstock food widely used in E. sinensis hatcheries in China. This encouraging result should facilitate more reliable hatchery production of this important aquaculture species.     

The effect of cyclooxygenase (COX) inhibitors on Japanese medaka (Oryzias latipes) reproduction parameters fed with high level of arachidonic acid (20:4 n-6)

Broodstock of mature Japanese medaka (Oryzias latipes Temminck and Schlegel, 1846) (mean weight 0.45 ± 0.03 g; age 6 months) were maintained in glass aquaria (8 males and 8 females in each aquarium). The fish were fed commercial feed (group C) or this feed was supplemented with arachidonic acid ARA (2 % of total fatty acids in feed; group A) and one of the COX inhibitors: resveratrol (group AR) or NS-398 (group ANS) with amount 20 mg kg^?1 BW day^?1 of one of the COX inhibitors. The effect of 2 weeks of feeding experimental diets on reproductive parameters (fecundity, embryo and larval survival, hatching rate, and larvae body weight) was analyzed. Larvae (obtained from experimental dietary treatments) were reared for 2 weeks. The percent of spawning female and fecundity was similar in dietary treatments. COX inhibitors in broodstock diet caused a decrease in embryo survival rate. Eggs of medaka from group ANS and AR revealed the lowest hatchability rate. In contrast, group A revealed a higher hatchability rate at the same time. Larval body weight after hatching was significantly the highest in this group. At the end of the experiment, larvae body weight ranged from 1.62 ± 0.43 mg in group AN to 2.89 ± 0.74 mg in group A. These results show that the COX inhibitors decreased gamete and larval quality regardless of high levels of ARA in broodstock diet.     

在含等量维生素E饲料中添加β-胡萝卜素和虾青素对仿刺参幼参抗应激能力的影响

在水温11．0～20．0℃、盐度35‰和pH值7．5的条件下,将初始平均体质量为3．46g的仿刺参（Aposticho-pusiaponicusSelenka）幼参放养在容水300L的塑料水槽中,A组投喂含90mg·kg-。β-胡萝卜素＋60mg·kg-1维生素E（VE）的饲料,B组投喂含60mg·kg-1虾青素和60mg·kg-1VE的饲料,以不添加上述3种物质的基础饲料作对照（C组）。饲养80d后,将A、B,及C组幼参直接放人盐度（用淡水和海水或加入海水晶,配制成盐度为0、5、10、15、20、25、30、35、40、45,及50）、氨（用NH4Cl配制成氨浓度（Nn3-N）0、0.5、1．0、2．0、4．0、8．0,及10mg·L-1）、温度（0、4、10、15、20、25、30、35,及40℃）急剧变化的1500mL的白色聚乙烧杯中,每个处理3个重复,测定存活率和体腔液中SOD活力等指标。应激处理期间,不投喂,24h换水一次并吸出排泄物。96h后,盐度、氨处理组的仿刺参存活率高于对照组,存活仿刺参体腔液中SOD活力显著低于对照组（P〈0．05）;但A、B组仿刺参在低温应激时,存活率与对照组差异不显著（P〉0．05）。结果表明：饲料中添加90mg·kg-1β-胡萝卜素＋60mg·kg-1VE或60mg·kg-1虾青素＋60mg·kg-1VE均能显著提高仿刺参对盐度和氨应激的抵抗能力（P〈0．05）,但抗低温应激的效果不显著（P〉0．05）。     

Effect of dietary supplementation of phospholipids and highly unsaturated fatty acids on reproductive performance and offspring quality of Chinese mitten crab, Eriocheir sinensis (H. Milne-Edwards), female broodstock

This study was conducted to determine the optimum phospholipids: highly unsaturated fatty acids (PL/HUFA) ratio in maturation diets for female Chinese mitten crab, Eriocheir sinensis broodstock. Five isolipidtic and isonitrogenous diets were formulated to contain different amounts of pork lard, fish oil and soy lecithin with resulting PL/HUFA levels (%dry weight) of 1.4/0.3 (Diet 1), 1.6/2.5 (Diet 2), 2.3/2.0 (Diet 3), 3.8/1.5 (Diet 4) and 5.1/0.8 (Diet 5). Diet 1 lacked supplemental fish oil and soy lecithin and served as the control. Each of the five formulated diets was fed to a total of 150 female crabs for a period of 7 months. All diet treatments were triplicated with 50 crabs stocked in a pond as a replicate. After 6 months, male crabs were introduced into the ponds where females were kept, mating, spawning and egg hatching (in seawater) occurred in the following month. The nutritional value of various formulated diets was assessed based on survival, gonadosomatic index (GSI), egg production per female, fecundity (eggs/g female weight) of the females fed those diets and egg and larval (newly hatched zoea I larvae) quality.Females fed Diet 1 had the lowest GSI, egg production per female and fecundity while no significant difference were found for survival, hepatosomatic index (HSI) and the percentage of female spawned among the diet treatments (P > 0.05). Although there were no significant differences in egg diameter, egg wet or dry weights among all treatments (P > 0.05), the highest and the second highest proportions of essential fatty acids (EFA), i.e. 20:5n-3 (EPA), 22:6n-3 (DHA) and HUFA were found in the eggs produced by the females fed Diet 3 and Diet 2, respectively. Statistical analysis showed that EPA, DHA and HUFA in eggs produced by females fed Diet 3 were significantly higher than those from the other treatments (P < 0.05). Meanwhile, zoea I larvae from crabs fed Diet 3 had significantly larger carapace length than those from the other four treatments (P < 0.05). The zoea I larvae from crabs fed Diet 2 and Diet 3 also showed generally better tolerance to starvation and osmotic shock.In conclusion, our results indicated that diet included levels of PL/HUFA around 1.6/2.5 or 2.3/2.0 (% dry weight) fed female E. sinensis broodstock supported increased fecundity and elevated level of HUFA in egg, which in turn resulted in improved overall quality of newly hatched larvae.     

中华绒螯蟹亲蟹渗透压调节和抗氧化系统对盐度的响应

探讨了中华绒螯蟹亲蟹血清离子和渗透压对盐度的响应以及肝胰腺抗氧化能力与盐度的关系.设立4个盐度组(盐度6、12、18、24)和1个淡水对照组,检测第4天和第20天时中华绒螯蟹亲蟹血清中Na+、K+、Cl-浓度、渗透压以及肝胰腺超氧化物歧化酶(SOD)、过氧化氧酶(CAT)活性和还原型谷胱甘肽(GSH)、丙二醛(MDA)...     

繁殖季节长江口斑尾刺虾虎鱼的形态、生殖力与卵巢组织学特征

在繁殖季节研究了斑尾刺虾虎鱼的形态、生殖力与卵巢组织学特征。结果表明,斑尾刺虾虎鱼全长(TL)与体长(SL)、头长(HL)与体长(SL)、体长(SL)与体高(BD)、体重(BW)与空壳重(SW)、体重(BW)与体长(SL)的相关关系分别为:TL=0.779 6SL+1.793 9;HL=0.299 9SL+7.288;SL=0.783 2BD+7.324 9;BW=0.818 4SW-4.979 6;BW=0.062 9SL2.331 5。斑尾刺虾虎鱼个体绝对生殖力(F)为6 328~59 878 egg,与体长(SL)、空壳重(SW)、卵巢重(OW)的相关关系分别为F=94.972SL2-4 832.2SL+833 435;F=83.823SW+14 084;F=507.54OW+13 190。个体绝对生殖力(F)与体长、空壳重、卵巢重、成熟系数(GSI)的多元回归方程为:F=2 375.54+525.67SL-31.44SW+199.43OW+261.74GSI。斑尾刺虾虎鱼体长相对生殖力(FL)平均为88±31 egg/mm,体重相对生殖力(FW)平均为157±54 egg/g。平均卵径为1.22±0.24 mm。斑尾刺虾虎鱼IV期卵巢以第IV时相卵母细胞为主,第IV时相晚期卵母细胞开始出现油球,细胞核偏移和变形,放射带明显;Ⅴ期卵巢的卵细胞游离,卵膜外的二层滤泡膜脱落,卵细胞的外层分别有胶膜、放射带和质膜。     

Suppression of color degradation of yellowtail dark muscle during storage by simultaneous dietary supplementation of vitamins?C and E

The commercial value of yellowtail Seriola quinqueradiata meat is often reduced by color deterioration of the dark muscle during storage. The objective of this study was to investigate the effect of simultaneous dietary supplementation of vitamin C (VC) and vitamin E (VE) to cultured yellowtail on color degradation of the dark muscle during storage. Yellowtail were fed for 6 or 11 days on a diet containing 1% VC and 1% VE (vitamin group) or without these vitamins (control group). The amounts of VC and VE in the dark muscle of the vitamin group tended to be higher than those of the control group. During the storage of sliced meat at 23 and 4°C, the decreases in a* value (redness) of the dark muscle of the vitamin group was slower than those of the control group. The formation of metmyoglobin, which can occur along with myoglobin oxidation, in the dark muscle of the vitamin group was slower than that of the control group. These results suggest that simultaneous feeding of high amounts of VC and VE for a short period to yellowtail before harvesting could suppress the color deterioration of the dark muscle during storage.     

Dietary phospholipids requirement of the early juvenile (C1) swimming crab,Portunus trituberculatus

A 30‐day experiment was conducted to investigate the effect of phospholipids (PLs) on growth performance, survival, fatty acid profile and gene expression of the early juvenile (C1) swimming crab (Portunus trituberculatus). Five semi‐purified diets were formulated with graded PLs levels (0%, 1%, 2%, 4% and 8%). Each diet was fed to four replicates of crabs (30 crabs per replicate, initial weight: 8.4 ± 0.1 mg). In this study, crabs fed diets with 2%, 4% and 8% PLs had significantly higher survival rates than crabs fed with 0% and 1% PLs. Crabs fed diets with 0% and 1% PLs had significant lower weight gain (WG) than crabs fed with 8% PLs. But crabs fed with diets containing 2%, 4% and 8% PLs showed no significant difference in WG. Besides, the content of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in whole body was higher than that in diets, but the monounsaturated fatty acids (MUFA) content showed an opposite trend. The EPA and DHA content in whole body increased with the increase in dietary PLs. Moreover, the moulting number increased with the increasing dietary PLs levels, the lowest moulting number was observed in crabs fed diets without supplementation of PLs. The ecdysteroid receptor (EcR) was found to be significantly up‐regulated by PLs levels. This study demonstrated that 2% PLs could meet the requirement of early juvenile (C1) swimming crab based on the growth and survival. And 4%–8% PLs supplemented in diets could reduce the leaching of feed.