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本实验旨在研究低盐胁迫(盐度为3)下,饲料添加不同含量的甘露寡糖(mannan oligosaccharide, MOS)对凡纳滨对虾(Litopenaeus vannamei)生长性能、抗氧化能力、免疫力和肠道微生物的影响。在低盐条件下,实验组对虾(0.68 ± 0.01)g分别饲喂含有2 g/kg、4 g/kg和8 g/kg MOS的实验饲料,并将在盐度25和3条件下饲喂0 g/kg MOS饲料的对虾作为海水对照组和低盐对照组,实验养殖周期为42天。结果表明：1)低盐对照组对虾的增重率和特定生长率极显著低于海水对照组(P＜0.01)。与低盐对照组相比,4 g/kg MOS组对虾的特定生长率,8 g/kg MOS组对虾的增重率、特定生长率和肥满度显著升高(P＜0.05)。2)与海水对照组相比,低盐条件下各处理组对虾肝胰腺总超氧化物歧化酶、谷胱甘肽硫基转移酶活力显著降低(P＜0.05),低盐对照组和2 g/kg MOS组丙二醛含量显著升高(P＜0.05),而4 和8 g/kg MOS组丙二醛含量恢复到海水对照组水平(P >0.05)。3)α多样性分析显示,低盐胁迫对肠道菌群多样性无显著影响(P＜0.05),而4和8 g/kg MOS组对虾肠道菌群丰富度(ACE, chao1)指数显著高于两个盐度对照组(P＜0.05)。另外,β多样性分析显示,海水对照组对虾肠道微生物与低盐条件下的各组都发生了明显分离(P＜0.05)。4)相比于两个盐度对照组,2和4 g/kg MOS组对虾肠道变形菌门相对丰度显著降低(P＜0.05),厚壁菌门和疣微菌门相对丰度显著上升(P＜0.05)。5)利用Tax4Fun预测L3水平功能,结果显示,与海水对照组相比,低盐胁迫对肠道微生物介导的功能影响较弱,而4 g/kg MOS显著提高了对虾肠道微生物介导的大多数与代谢和免疫相关通路的表达量。综上所述,饲料添加MOS能提高低盐胁迫下凡纳滨对虾的生长性能、抗氧化能力和免疫力,并通过调节肠道微生物组成和结构提高对虾应对低盐环境的能力。综合以上结果表明,实现低盐条件下凡纳滨对虾的健康养殖的饲料MOS最适添加量为4 g/kg。 相似文献
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本实验旨在研究饲料中添加酵母水解物对凡纳滨对虾在低盐度胁迫条件下非特异性免疫和抗氧化能力的影响。选取凡纳滨对虾[初始体质量（15.82±0.08）g],平均分为2组,对照组投喂基础饲料（Y0）,实验组投喂添加了3%酵母水解物的实验饲料（Y3）,在室内养殖15d后分别放入盐度为4‰（S4）和28‰（S28）的水体中进行盐度胁迫实验,每组6个重复,每个重复30尾虾（根据饲料和盐度不同组合,分组命名为Y0S4、Y0S28、Y0S3、Y0S28）。结果表明：饲料中添加3%酵母水解物对凡纳滨对虾血清酚氧化酶（PO）、总一氧化氮合成酶（TNOS）活性没有显著影响,但低盐度胁迫1h时,Y3S4组PO、TNOS活性显著高于Y0S4组;盐度因素对PO、TNOS活性产生显著影响,低盐度胁迫1h时,S28组PO、TNOS活性显著高于S4;饲料中添加3%酵母水解物显著提高了凡纳滨对虾肝胰腺超氧化物歧化酶（SOD）活性;盐度因素对酸性磷酸酶（ACP）活性产生了显著影响,S28组ACP活性显著高于S4。由此可见,在饲料中添加酵母水解物能够提高凡纳滨对虾肝胰腺SOD活性,提高对虾的抗氧化能力;在遭遇低盐度胁迫时,对虾能迅速恢复PO、TNOS活性至正常水平,从而提高凡纳滨对虾的抵抗不良环境的能力。 相似文献
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为研究新型抗菌物质凹凸棒土对凡纳滨对虾生长性能、消化能力、抗氧化能力和肠道菌群的影响。实验选取初始体质量为（0.17±0.01）g的幼虾，分别投喂0% (对照)、0.1% (S1)、0.2% (S2)、0.4% (S3)、0.8% (S4)含量的凹凸棒土饲料，以及含有0.2%恩诺沙星抗生素对比组饲料(E)，养殖8周。凹凸棒土处理组对虾增重率均未见显著提升，但S1、S2组对虾存活率显著高于对照组，与E组没有显著差异。相比于对照组，凹凸棒土添加组提高了幼虾肠道淀粉酶活性，以及肝胰腺中脂肪酶活性。S2组对虾血清酸性磷酸酶和碱性磷酸酶活性显著高于对照组和E组。S3和S4组对虾的肝胰腺超氧化物歧化酶活性显著高于其他组。肠道菌群α多样性分析显示，S2组肠道微生物丰富度Chao1指数有所下降，但是覆盖度显著提高。与对照组相比，S2组部分属的丰度调节作用与恩诺沙星类似。根据代谢通路差异分析与种间关系作图，与E组相比，凹凸棒土能够上调牛磺酸、谷胱甘肽、半乳糖和脂肪酸代谢的4条通路，并增加肠道微生物种间合作能力。在饲料中添加0.1%~0.2%的凹凸棒土能够显著提高凡纳滨对虾的成活率、消化能力和肝胰腺抗氧化能力，并在调节对虾肠道部分菌群丰度方面起到类似于恩诺沙星的作用，能改善肠道菌群结构和相应功能。 相似文献
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为比较不同养殖盐度下凡纳滨对虾(Litopenaeus vannamei)抗氧化活力及非特异性免疫状态,将平均体长为(10.6±1.7)cm的对虾分为高盐度组(20‰)和低盐度组(5‰),饲养2周后,测定肝胰腺和血清中的抗氧化酶及免疫相关酶活力。结果显示,凡纳滨对虾在低盐度下肝胰腺中谷胱甘肽过氧化物酶(GPx)、超氧化物歧化酶(SOD)活力及总抗氧化能力(T-AOC)均显著低于高盐度组,丙二醛(MDA)含量高于高盐度组;在低盐度下,血清中GPx活力、T-AOC显著低于高盐度组,MDA含量高于高盐度组;低盐度下,对虾肝胰腺谷丙转氨酶(GOT)和谷草转氨酶(GPT)活力显著下降,而血清GOT和GPT活力显著升高;低盐度下,血清和肝胰腺中的酸性磷酸酶(ACP)和碱性磷酸酶(AKP)活力均显著低于高盐度组。结果表明,低盐度条件下凡纳滨对虾血清和肝胰腺的抗氧化活力和免疫酶活力均受到抑制,脂质过氧化程度升高,肝胰腺受到一定程度的损伤。 相似文献
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饲料中黄曲霉毒素B1对凡纳滨对虾生长、肝胰腺和血淋巴生化指标及肝胰腺显微结构的影响 总被引：1，自引：1，他引：0
实验设置黄曲霉毒素B1(AFB1)为0、400、800、1200,1600、2000μg/kg6组饲料,饲养初始体质量为(0.3±0.02)g的凡纳滨对虾,经过8周的生长实验观察饲料中AFB1对凡纳滨对虾生长、体营养成分组成、肝胰腺显微结构以及血淋巴和肝胰腺生化指标的影响。实验结果表明:随着饲料中AFB1的增加,各组全虾粗蛋白量无显著性差异,1600μg/kg组和2000μg/kg组的全虾粗脂肪量高于其他组。AFB1为1200μg/kg时对虾增重率最低(304.67%),2000μg/kg时增重率显著高于其他组,但成活率最低(58.33%)。随着饲料中AFB1的升高酶活性普遍呈下降趋势。2000μg/kg组肝胰腺中总抗氧化能力(T-AOC)显著下降(P<0.05),1600μg/kg组肝胰腺中谷胱甘肽S转移酶(GST)、超微量ATP酶和超氧化物歧化酶(SOD)酶活力最低,但血淋巴中GST显著高于其他各组(P<0.05)。从凡纳滨对虾肝胰腺的组织切片可观察到,饲料中含有的AFB1越高,肝胰腺被破坏程度越高。随着饲料中AFB1含量增加,对虾肝胰腺中AFB1残留量逐渐增加,2000μg/kg组对虾肝胰腺中AFB1含量最高(95.49μg/kg),各实验组肌肉中无AFB1残留。 相似文献
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饲料中添加核苷酸对凡纳滨对虾幼虾生长、肠道形态及抗氧化酶活力的影响 总被引：2，自引：1，他引：1
本实验旨在研究外源核苷酸混合物对凡纳滨对虾(Litopenaeus vannamei)幼虾生长性能、体组成、中肠肠道形态和抗氧化酶活力的影响。选取960尾初始体质量为(1.01±0.02)g的凡纳滨对虾,随机分为8组,分别投喂基础饲料和添加5种核苷酸混合物(5′-腺苷酸∶5′-胞苷酸∶5′-尿苷酸二钠∶5′-肌苷酸二钠∶5′-鸟苷酸二钠=1∶1∶1∶1∶1,mix-NT)的实验饲料,各实验组添加量分别为0.1、0.2、0.4、0.6、0.8、1.0和1.2 g/kg饲料,养殖期为7周。结果显示,饲料中添加5种核苷酸混合物对凡纳滨对虾的特定生长率(SGR)和饲料系数(FCR)影响不显著(P>0.05)。外源核苷酸显著影响凡纳滨对虾全虾水分含量(P<0.05),但对全虾粗蛋白、粗脂肪和灰分含量影响不显著(P>0.05)。肝胰指数(HSI)随饲料中核苷酸添加量的增加而显著升高(P<0.05),在0.6 g/kg组达到最高。0.4 g/kg组的肝胰腺谷草转氨酶(GOT)和谷丙转氨酶(GPT)活力及尿酸(UA)含量最低,但与对照组相比差异均不显著(P>0.05)。中肠肠壁厚度和肠绒毛高度均随着核苷酸添加量的增加呈先升高... 相似文献
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家蝇蛆粉替代鱼粉对凡纳滨对虾消化酶、转氨酶活性和肝胰腺组织结构的影响 总被引：2，自引：0，他引：2
试验采用28%鱼粉饲料为基础,以家蝇蛆粉分别替代20%、40%、60%、80%和100%的鱼粉配制5种试验饲料,投喂初始体质量为0.56 g的凡纳滨对虾（Litopenaeus vannamei）45 d,研究了蝇蛆粉对凡纳滨对虾消化酶、转氨酶活性和肝胰腺结构的影响。结果显示,替代组对虾肝胰腺、胃和肠道消化酶活性与对照组相比差异不显著（P＞0.05）。替代组对虾肝胰腺谷丙转氨酶（ALT）、谷草转氨酶（AST）活性均低于对照组,但差异不显著（P＞0.05）;随着替代水平的增加,血清ALT活性在100%替代组、AST活性在60%-100%替代组显著降低（P＜0.05）。与对照组相比,20%-60%替代组肝胰腺上皮细胞中空泡增多,并且出现未知物质;替代水平高于60%时肝胰腺结构损伤严重。结果表明,蝇蛆粉替代水平在60%以下时,对凡纳滨对虾消化酶和转氨酶活性没有显著影响,对肝胰腺结构损伤不明显。 相似文献
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植物乳酸杆菌对凡纳滨对虾生长、消化酶活性和肠道组织形态的影响 总被引：1，自引：0，他引：1
将体质量(8.10±0.13)g的凡纳滨对虾放养在室内500L玻璃纤维水桶中,以不同剂量(0、0.5%、1.0%和2.0%)的植物乳酸杆菌菌液(密度109 cfu/mL)拌料投喂,观察凡纳滨对虾的生长、消化酶活性和肠道组织结构的变化。结果显示,投喂15d后,0.5%和1%菌液组对虾的平均体质量、质量增加率和特定生长率均显著高于对照组(P0.05),饲料系数显著降低(P0.05);0.5%菌液组对虾肝胰腺消化酶和肠道消化酶活性显著增强(P0.05),对虾肠上皮细胞高度显著增加(P0.05)。研究结果表明,投喂0.5%植物乳酸杆菌可显著提高凡纳滨对虾消化酶活性和肠上皮细胞高度,促进对虾生长。 相似文献
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[目的]本实验旨在研究低鱼粉饲料 中添加羟基蛋氨酸硒(HMSe)对凡纳滨对虾(Litopenaeus vannamei)生长性能、抗氧化能力及抗亚硝酸盐胁迫的影响。[方法]实验选用初始体质量为(0.90±0.05)g的凡纳滨对虾,分别投喂HMSe添加水平为0.000、0.375、0.750、1.500和2.250 mg/kg的实验饲料,命名为HMSe0 、HMSe1、HMSe2、HMSe3和HMSe4,每组3个重复,养殖8周。养殖实验结束后,进行12 h 的亚硝酸盐胁迫实验。[结果]结果表明,凡纳滨对虾的终末体质量(FBW)、增重率(WG R)和饲料效率(FE)随着饲料中HMSe水平的增加呈现先升高后下降的趋势,并在HMSe2组达到峰值。随着饲料中HMSe水平的提高,对虾全体和肌肉中的硒含量均显著增加,而全虾粗蛋白和粗脂肪的含量呈现先升高后降低的趋势,并分别在HMSe2组和HMSe1组达到最大值。HMSe4组中凡纳滨对虾的血清谷胱甘肽过氧化物酶(GSH-Px)和肝胰腺过氧化氢酶(CAT)活性显著高于HMSe0组。亚硝酸盐胁迫显著影响凡纳滨对虾的存活率。与胁迫前比较,胁迫后对虾肝胰腺中MDA含量升高,GST、CAT和T-SOD的活性降低,而补充适量的HMSe可减轻这些负面影响。根据凡纳滨对虾胁迫后成活率的二次多项式回归分析,低鱼粉饲料中凡纳滨对虾的HMSe最适添加量为1.350 mg/kg。[结论]综上所述,在低鱼粉饲料中添加0.750~1.350 mg/kg HMSe,能够提高凡纳滨对虾的生长性能、饲料利用率和抗亚硝酸盐胁迫的能力。 相似文献
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Shun Watanabe Jun Aoyama Seishi Hagihara Bunpei Ai Rhodora V. Azanza Katsumi Tsukamoto 《Fisheries Science》2013,79(3):375-383
Anguilla luzonensis and A. huangi were each described in 2009 using eels obtained from northern Luzon Island. We examined the taxonomic status of these two groups of eels using morphological and molecular genetic characters. There were no significant differences in two vertebrae counts between eels of A. luzonensis and A. huangi. Mitochondrial 16S ribosomal RNA and cytochrome b genes sequences were obtained and compared among 28 specimens of A. luzonensis, the holotypes of A. luzonensis and A. huangi, and one specimen of the other 15 anguillid species. The specimens of A. luzonensis exhibited almost identical sequences, including the holotype, with only a few site differences, and the genetic difference between the holotypes of A. luzonensis and A. huangi was within the range of differences of specimens of A. luzonensis. The other anguillid species were genetically very different from A. luzonensis and A. huangi, although A. interioris is a closely related species. It is clear that A. luzonensis and A. huangi are the same species, and according to the principle of priority in zoological nomenclature, A. luzonensis Watanabe, Aoyama, and Tsukamoto, 2009 is the valid species name, and A. huangi Teng, Lin, and Tzeng, 2009 is a junior synonym of A. luzonensis. 相似文献
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The effects of exposing the eggs of Pacific threadfin and amberjack eggs (AEs) to different concentrations of hydrogen peroxide for 5 min on hatch rate and survival were assessed in a series of experiments using a petri dish model rearing system. Despite significant inter‐batch variation in hatch rate, it was shown that eggs of both species could be safely exposed to up to 11 340 mg L−1 H2O2 for 5 min. Exposure to 34 230 mg L−1 H2O2 for 5 min was shown to be lethal to AEs at a late stage of development. In two further experiments, it was demonstrated that Pacific threadfin eggs were resistant to all tested concentrations of a range of polyvinylpyrrolidone iodine (PVP‐I) concentrations and contact times (up to 1000 mg L−1 PVP‐I for 10 min). The level of bacteria adhering to the eggs of both species was highly variable. Where eggs were heavily colonized (>104 cfu egg−1), hydrogen peroxide concentrations of at least 11 340 mg L−1, or PVP‐I concentrations higher than 500 mg L−1 for 10 min, were required for effective sterilization. In less colonized batches, rinsing in sterile seawater or exposure to lower (550 mg L−1) concentrations of H2O2 was sufficient to result in high apparent levels of surface sterility (<1 cfu egg−1). 相似文献
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Nuhman Usman Bambang Irawan Agoes Soegianto 《Journal of the World Aquaculture Society》2013,44(4):547-556
The purpose of this study was to evaluate the acute toxicity of lead for different life stages of shrimp, Litopenaeus vannamei, and to determine the effect of its sublethal concentrations on osmoregulatory capacity (OC) as well as the possible histological alteration in the gills of juvenile shrimp. The 24‐, 48‐, and 96‐h LC50 values for lead to L. vannamei increased progressively with increasing life stage, from nauplii < zoeae < mysis < postlarvae < juvenile. After 15‐d exposure to 3.25, 6.50, and 9.75 mg Pb/L, the OC values of exposed shrimp were reduced by 39, 73, and 157%, respectively compared to control animals. Compared to controls, the lead concentrations in gill tissues increased significantly by 127,500, 137,500, and 141,000% in shrimps exposed to 3.25, 6.50, and 9.75 mg Pb/L, respectively. After lead exposure, hemocytic congestion in efferent vessels and multiple hyperplasia were observed in gill filaments, resulting in narrowed hemolymphatic lacuna. The histopathological effects increased with increasing Pb concentration. 相似文献
14.
对驼背鲈(Chromileptes altivelis)的胚胎发育及仔、稚、幼鱼的形态特征进行了详细的观察与研究,描述了从受精卵到仔、稚、幼鱼各发育期的时间和形态特征变化。结果表明,在水温25-26℃、盐度30的海水中,受精卵历时27 h 25 min完成整个胚胎发育过程,经历从卵裂、囊胚、原肠、神经胚到肌节形成、各器官的逐渐形成、变化、完善等一系列的胚胎发育和变化过程;根据其卵黄囊消长情况、鳞片的覆盖状态、体色发生的不同变化以及第二背鳍和腹鳍的消长,将胚后发育分为仔、稚、幼鱼3个阶段。在水温22-26℃、盐度29-31、DO≥5 mg/L的条件下,2-3 d仔鱼卵黄囊消失,开口摄食;生长发育至31 d,仔鱼已变态进入稚鱼期;培育至57 d,稚鱼完成变态,成为幼鱼。第二背鳍棘和腹鳍棘的生长与收缩等石斑鱼类早期发育的共性生长特征及其体表特性体色变化特征为驼背鲈胚后发育过程中最明显的特征。 相似文献
15.
Effect of Temperature on Growth,Energy Budget,and Physiological Performance of Green,White, and Purple Color Morphs of Sea Cucumber,Apostichopus japonicus 
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下载免费PDF全文 Yucen Bai Yan Chen Yang Pan Libin Zhang Shilin Liu Xiaoshang Ru Lili Xing Tao Zhang Hongsheng Yang Jing Li 《Journal of the World Aquaculture Society》2018,49(3):625-637
As an intertidal species, Apostichopus japonicus is subject to diel and seasonal temperature fluctuations. Color variation is a distinct characteristic of A. japonicus, and a new color morph, purple A. japonicus, was recently found on the coast of Rushan, Weihai City. This study was conducted to compare the performance of green, white, and purple color morphs of A. japonicus at different water temperatures to help improving aquaculture technology and management. In this study, green, white, and purple color morphs of juvenile A. japonicus (1.5 ± 0.1 g) were cultured at 10, 14, 18, 22, and 26 C for 60 d, according to the suitable temperature range for sea cucumber growth. Temperature was shown to have a significant effect on growth, energy budget, and physiology of sea cucumbers (P < 0.05). Specific growth rates, feed conversion efficiencies, and the proportion of energy allocated to growth of all three color morphs were optimal at 18 C. Activities of the enzymes related with oxidative stress, immune response, and digestion were determined. Superoxide dismutase (SOD) and trypsin activities generally reached a maximum in all three color morphs at 18 C. The purple color morph of A. japonicus was higher in growth rate, food conversion efficiency, and proportion of energy allocated to growth than green and white color morphs at 18 and 22 C, consistent with its higher trypsin and SOD activity, indicating the mutual effect of growth and physiology. At 18, 22, and 26 C, the green color morph had the highest level of lysozyme activity and purple color morph had the lowest, indicating possible infection by external pathogens of green color morph, which might be caused by high temperature. These results suggested that the optimum temperature for culture of the three color morphs was approximately 18 C, the purple had a better adaption to high temperature, and the green and white color morphs may be more susceptible to thermal stress than the purple color morph. 相似文献
16.
Mulloway (Argyrosomus japonicus) occur in estuarine and coastal waters surrounding Australia, Africa, India, Pakistan, China, Korea and Japan, where they are important in fisheries. This study identified that mulloway in south-eastern Australia had similar growth rates, but matured at smaller lengths and younger ages, to those in South Africa and Western Australia. Growth of both sexes was similar to about 5 years, after which females grew faster and attained a greater maximum length than males. Female mulloway matured at 4–5 years of age with a L50 of 68 cm, whereas males matured at 2–3 years of age with a L50 of 51 cm. The commercial fishery in New South Wales was characterised by declining catches and a reduction in the proportion of mulloway of mature lengths in landings. During 2002–2005 commercial landings were dominated (83%) by fish within 15 cm of the current minimum legal total length of 45 cm and aged 2 and 3 years (>80%), even though mulloway can attain lengths of 200 cm and live >30 years. Estimates of the rates of instantaneous total mortality ranged between 0.34 and 0.45, whilst the rate of instantaneous natural mortality (M) was estimated to be approximately 0.12. Yield-per-recruit analyses indicated that mulloway in New South Wales are being growth overfished and substantial increases in yield could be achieved by increasing the length at first harvest. Values of the spawning potential ratio were below 0.2 under a range of mortality estimates, suggesting that mulloway are at risk of recruitment overfishing. These results suggest that the spawning stock of mulloway in south-eastern Australia has been depleted and that remedial management action is required to protect this iconic species. 相似文献
17.
Charles C. Mischke Matt J. Griffin Terrence E. Greenway David Wise 《Journal of the World Aquaculture Society》2013,44(2):288-292
Mosquitofish, Gambusia sp., have been spread throughout the world to biologically control mosquitoes. However, the fish has gained a reputation as an invasive species and has been implicated in displacing native aquatic species. Gambusia affinis are native to the southeastern United States and commonly occur in commercial channel catfish, Ictalurus punctatus, production ponds. We investigated effects of mosquitofish presence on zooplankton populations, water quality, disease occurrence, and fish production in experimental ponds. There were no differences between ponds with or without mosquitofish in numbers of calanoid copepods, cyclopoid copepods, total copepods, Bosmina sp., Ceriodaphnia sp., Moina sp., Daphnia sp., or total cladocerans. There were also no differences in copepod and cladoceran sizes. Copepod nauplii were more numerous during the summer months in ponds with mosquitofish. There were no differences in water quality variables (soluble reactive phosphorus, nitrate, nitrite, ammonia, total nitrogen, total phosphorus, pH) or phytoplankton density between ponds stocked with and without mosquitofish. Catfish production and disease occurrence were also similar between ponds with and without mosquitofish. Although mosquitofish may cause problems when stocked outside their native range, there does not appear to be any adverse effects of mosquitofish presence in catfish production ponds. 相似文献
18.
Recruitment strategy of swimming crab, Portunus trituberculatus, in Hiuchi-Nada, Japan 总被引：2，自引：0，他引：2
The recruitment strategy of swimming crabs, Portunus trituberculatus, was investigated by field observations and numerical experiments in Hiuchi-Nada, Japan. Calculated dispersal patterns of zoeal and megalopal stages in a three-dimensional numerical model reproduce observed patterns accurately. The temporal change of vertical migration patterns between the 1st and 2nd zoeas and the 3rd and 4th zoeas plays an important role in the process of recruitment of P. trituberculatus from spawning ground to nursery ground. 相似文献
19.
This study aimed to find out if dietary carotenoid (CD) supplement could make differences in survival, growth, pigmentation, and antioxidant capacity of characins Hyphessobrycon callistus, an ornamental fish. Two types of CD and its combination (AX — astaxanthin, BC — β-carotene, MX — 1:1 combination of AX and BC) at three concentrations (10, 20, and 40 mg/kg) were used resulting in nine pigmented diets. A diet without CD supplement served as control. No differences in growth and survival of the fish among treatments were found after 8 weeks rearing. Disregarding the types of dietary CD, AX dominated (> 98%) the body CD, indicating that this fish converted most dietary BC into body AX for storage. Body AX and BC content increased with increasing dietary CD concentration. Body AX in BC-fed fish was lower than that in both AX- and MX-fed fish. No difference in body AX was found between AX- and MX-fed fish, and in body BC in all pigmented fish. Serum total antioxidant status [TAS], serum antioxidant enzymes (superoxide dismutase [SOD], glutathione peroxidases [GPx]) and serum transaminases (alanine aminotransferase [ALT], aspartate aminotransferase [AST]) were chosen as indices of fish antioxidant capacity. Antioxidant activities changed with dietary CD type and concentration. Pigmented fish had lower SOD, GPx and ALT than control fish; dietary CD types only affected SOD and ALT in fish. AX-fed fish had the lowest SOD. Dietary AX had more numbers of negative correlations with antioxidant parameters in fish than BC. 相似文献
20.
《Journal Of Applied Aquaculture》2013,25(4):89-93
Abstract Effects of salinity on embryonic development and growth of African catfish, Clarias gariepinus, eggs and larvae were studied. Eggs were incubated at 27-29°C in 2,4,6,8, and 10 ppt sodium chloride. Rate of embryonic development was delayed in all salt solutions by 15, 15,28 and 30 minutes, in 2,4,6, and 8 ppt sodium chloride, respectively, when compared with the control group (0% salt); total mortality occurred at 12 hours after gastrula stage in the 10 ppt concentration. Percentage hatching was 45.1,47.7, 59.5,49.2, and 26.6% while percentage deformity was 10.4, 16.1, 52.0, 28.6, and 71.6% in 0, 2, 4, 6, 8, and 10 ppt salt treatments, respectively. There were significant differences (P <0.05) in the hatching percentage and in deformity percentage between 4, 6, and 8 ppt. Rate of yolk absorption was significantly faster in the control and 2 ppt salt treatments, but slower in 4, 6, and 8 ppt. Rate of increase in length was slower with increasing salinity. The optimum salinity for African catfish eggs and was between 0-2 ppt and acceptable up to 6 ppt. The results suggest that increasing salinity delayed hatching and development of African catfish eggs and larvae, respectively, as well as increased the deformity of the larvae. 相似文献