虎嘉鱼食性及食物消化的研究     

周仰景  吴万荣 《水产学杂志》1990,3(1):67-72

本文报导虎嘉鱼(Hucho bIeekeri K.)的食性及食物消化的研究结果,其食性以水生昆虫和鱼类为主食。虎嘉鱼是较有经济价值的鱼类,这一研究对虎嘉鱼的开发和利用及人工养殖提供了科学依据。  相似文献   

Evaluation of genetic diversity of eight grouper species <Emphasis Type="Italic">Epinephelus</Emphasis> spp. based on microsatellite variations   总被引：1，自引：0，他引：1  

Worawut Koedprang  Uthairat Na-Nakorn  Masamichi Nakajima  Nobuhiko Taniguchi 《Fisheries Science》2007,73(2):227-236

ABSTRACT:   Genetic diversity among eight species of grouper, Epinephelus bleekeri , E. coioides , E. malabaricus , E. ongus , E. akaara , E. maculatus , E. merra and E. fuscoguttatus , was studied using six microsatellite loci, Em-01 *, Em-03 *, Em-07 *, Em-08 *, Em-10 *, and CA-07 *, with the aim of exploring the feasibility of using microsatellite data for species identification. The results showed high levels of genetic differentiation among species ( F _ST  = 0.4403 and R _ST  = 0.4954). Species identification based on fixed allelic differences was possible between E. coioides , E. ongus , and E. fuscoguttatus at Em-01 * and between E. fuscoguttatus and E. ongus at Em-08 *. Private alleles were found in all species, except for E. ongus . Pairwise F _ST ranged 0.238–0.578 ( P  < 0.008 Bonferroni correction), and Nei's genetic distance ranged 0.433–2.710. Size homoplasy was observed at Em-03 * 157 allele, which was characterized by a T–C transition at the 119th nucleotide site of PCR products. The genetic assignment test unambiguously assigned each individual to the correct species. Thus, this test can be used for species identification of unknown individuals when the multilocus genotypes of the six microsatellite loci are available. The phylogenetic (neighbor-joining) tree, which was constructed based on the genetic distance matrix, separated the eight grouper species into two main groups.  相似文献   

Diurnal variation of tryptic activity in larval stage and development of proteolytic enzyme activities of malabar grouper (Epinephelus malabaricus) after hatching     

Aya Fujii  Yuko Kurokawa  Shin''ichiro Kawai  Kenzo Yoseda  Shigeki Dan  Aya Kai  Masaru Tanaka   《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):68-76

Diurnal variation in tryptic activity and developmental changes in proteolytic enzyme activities of malabar grouper larvae (Epinephelus malabaricus) were examined. Five different groups were prepared for the experiment of diurnal variation of tryptic activity in larvae: larvae were fed Thai-type rotifers Brachionus rotundiformis from the time of mouth opening, fed rotifers from 6 h after mouth opening, 12 h, 24 h and not fed rotifers (starved control). The experimental tanks were placed in temperature-controlled baths at 28 °C under 24 h light. Developmental changes in proteolytic activity of trypsin and pepsin-like enzyme were measured from hatching to 57 days after hatching (DAH).

The tryptic activity of all fed groups showed the same pattern, and the diurnal variation of tryptic activity was clearly observed from 3 to 6 DAH. The highest tryptic activities were found at 19:00, and the activities were lowest from 01:00 to 07:00. In contrast, that of non-fed larvae was low compared to the fed groups, however the diurnal variation of tryptic activity was shown same tendency to the fed groups. Interestingly, both groups (fed and non-fed) were exhibited a circadian rhythm under the 24 h light conditions and delaying of first-feeding. Tryptic activity of larvae notably increased from 40 to 45 DAH and markedly decreased at 52 DAH. In contrast to the tryptic activity, that of pepsin-like enzyme clearly increased from 47 to 51 DAH. The results suggest that a functional change of protein digestion occurs from 40 to 50 DAH related with metamorphosis in malabar grouper. These results could contribute to determining appropriate feeding schedules, such as feeding time, frequency and optimal time to change food items, in mass-scale production of the present species.  相似文献   

Quantitative l-lysine requirement of juvenile grouper Epinephelus coioides   总被引：3，自引：0，他引：3  

Z. LUO  Y-J. LIU  K-S. MAI  L-X. TIAN  X-Y. TAN  H-J. YANG  G-Y. LIANG  & D-H. LIU 《Aquaculture Nutrition》2006,12(3):165-172

An 8‐week feeding trial was conducted to determine the quantitative lysine requirement of juvenile grouper Epinephelus coioides (initial mean weight: 15.84 ± 0.23 g, mean ± SD) in eighteen 500‐L indoors flow‐through circular fibreglass tanks provided with sand‐filtered aerated seawater by feeding diets containing six levels of l ‐lysine ranging from 19.2 to 39.5 g kg^?1 dry diet in 4 g kg^?1 increments. The diets, in which 250 g crude protein kg^?1 diet came from fish meal and soybean protein concentrate, and 230 g kg^?1 from crystalline amino acids, were formulated to simulate the amino acid profile of 480 g kg^?1 whole chicken egg protein except for lysine. Each diet was assigned to three tanks in a completely randomized design. Grouper were fed to apparent satiation twice daily during the week and once daily on weekends. Weight gain and specific growth rate increased with increasing levels of dietary lysine up to 27.2 g kg^?1 (P < 0.05) and remained nearly the same thereafter (P > 0.05). Feed efficiency was the poorest for fish fed the lowest lysine diet (P < 0.05) and showed no significant differences among other treatments (P > 0.05). Survival could not be related to dietary treatments. Body composition remained relatively constant except for lipid contents in muscle and liver. Total essential amino acid contents in liver increased with dietary lysine level although there was a slight decline for fish fed the highest lysine level of diet. Plasma protein content increased with increasing dietary lysine level (P < 0.05), but cholesterol, triacylglycerol and glucose contents were more variable and could not be related to dietary treatments. Dietary lysine level significantly influenced morphometrical parameters (condition factor, hepatosomatic index and intraperitoneal fat ratio) of juvenile grouper (P > 0.05). Broken‐line analysis of weight gain indicated the dietary lysine requirement of juvenile grouper to be 28.3 g kg^?1 diet or 55.6 g kg^?1 dietary protein.  相似文献   

植酸酶在点带石斑鱼配合饲料中的应用   总被引：6，自引：0，他引：6  

阮成旭  袁重桂  石祥柱 《福建水产》2005,(1):13-16

在植物性饲料含量分别为12．7％和32．7％的点带石斑鱼的配合饲料中按比例添加植酸酶，通过32d的养殖，与对照组相比，结果显示添加植酸酶可以促进石斑鱼的生长，提高石斑鱼的相对增重率，降低饲料系数。  相似文献   

大川河水生生物与虎嘉鱼的生态位     

吴万荣 《水产学杂志》1989,2(1):23-33

本文提出对大川河永生生物与虎嘉鱼生态位的初步研究结果:①大川河水生生物中藻类植物53属,浮游动物21属,水生昆虫14属,鱼类8属(9种)。②虎嘉鱼的生态位在大川河水生生物中处于能量的终极,食物链的顶端。  相似文献   

福建南部养殖石斑鱼暴发性疾病流行调查   总被引：1，自引：0，他引：1  

龚艳清  陈信忠  王军  苏亚玲  俞秀霞  黄丽莎  苏永全 《福建农林大学学报(自然科学版)》2006,35(5):532-537

近年来福建南部网箱养殖石斑鱼常暴发急性传染病,经试验确认的传染病病原有神经坏死病毒、微孢子虫、本尼登虫以及多种弧菌.由神经坏死病毒引起的病毒性神经坏死病表现典型的神经症状,中枢神经组织和视网膜细胞严重空泡坏死;微孢子虫病表现为腹部、生殖腺、肝脏、肌肉等组织寄生大量孢子囊;本尼登虫主要寄生于石斑鱼的体表;感染的细菌主要有溶藻弧菌、副溶血弧菌以及河流弧菌等10种,这些菌多为条件致病菌.调查结果表明,病毒性神经坏死病是该地区养殖石斑鱼最常见危害也最大的传染病.  相似文献   

石斑鱼生长激素基因的合成及其在拟南芥中的表达   总被引：4，自引：0，他引：4  

肖生科  王磊  胡治球 《西北农林科技大学学报(自然科学版)》2004,32(9):57-60,65

为了使石斑鱼生长激素基因适合在植物中表达,重新合成了石斑鱼生长激素基因,对其密码子进行了优化,把合成的基因构建于植物表达载体pBI121上并转化模式植物拟南芥,获得了30个转基因抗性植株。对24株PCR阳性苗进行Northernblotting分析,结果表明,鱼类生长激素基因可以在转基因植物中表达,其表达在不同的转基因植株中存在明显差异,表达最强的植株与最弱的植株相比,二者表达量差异达到43倍。  相似文献   

逆转录聚合酶链式反应(RT-PCR)检测5种养殖石斑鱼的神经坏死病毒   总被引：9，自引：2，他引：9       下载免费PDF全文

陈信忠  苏亚玲  龚艳清  黄丽莎  俞秀霞  苏永全 《中国水产科学》2004,11(3):202-207

神经坏死病毒(Nervous necrosis virus)是导致多种海水鱼类神经性病害的致病原.发病及死亡的石斑鱼除了表现神经异常症状外,无明显的临床病症,体表及内脏组织也未发现明显病变及寄生虫感染.2003年4～8月,应用逆转录聚合酶链式反应(RT-PCR)技术从福建南部人工养殖的5种石斑鱼即紫石斑鱼(Epinephelus lanceolatus)、马拉巴石斑鱼(E. malabaricus)、青石斑鱼(E. awoara)、赤点石斑鱼(E. akaara)和云纹石斑鱼(E. moara)中检出5个神经坏死病毒分离株.检测了76份石斑鱼样品,这些石斑鱼NNV病毒的平均感染率约为90%.对这些病毒的RT-PCR产物421 bp核酸进行了测序和序列分析,其相同的序列超过99%.将这些序列与GenBank的石斑鱼(Epinephelus spp.)神经坏死病毒相关基因序列作比较,同源性在97%以上.对神经坏死病毒在石斑鱼体内的分布也进行了分析,在脑和眼组织的检出率最高,部分病鱼的肝、脾和肾组织也能检出病毒.结合流行病学特征,可确认神经坏死病毒为该传染病的主要致病原.RT-PCR方法是检测NNV等病原的一种理想的诊断方法.  相似文献   

赤点石斑鱼病毒性神经坏死症的组织病理和电镜观察   总被引：2，自引：3，他引：2  

林蠡 《水产学报》2005,29(4):519-523

用逆转录-聚合酶链式反应（RT-PCR）检测患病赤点石斑鱼苗，呈Beta诺达病毒阳性。光学显微镜下观察到病鱼的脑、视网膜、脊髓有空泡．在脑部，空泡主要分布在端脑、间脑和小脑。受感染的细胞明显收缩、致密变化和嗜碱性。包涵体常为圆形，大小不一。透射电镜下，在感染细胞的细胞质可观察到含有病毒粒子的致密体。病毒粒子呈等面体，无外膜，直径为25～28nm，随机分布在细胞质或在致密体内排列成品格状。致密体大小不一。偶尔观察到较大致密体的外膜已破裂，病毒粒子被释放到细胞质。  相似文献