共查询到20条相似文献，搜索用时 46 毫秒
1.
褐菖鲉生长缓慢，在浙江南麂海域2001年4月30日放养0．9g的苗种，至2001年6月7日达8.3g，当年底达24.8g，2003年6月26日达112.3g。总养殖成活率20．1％，平均日增重0．14g，平均增重率0．62％。秋末至夏初低水温期是其主要生长期。冬春季养殖成活率高于秋夏季，第一年夏季养殖成活率低，仅28．1％。饵料系数为3．6，食性为杂食性，对网箱具有明显的清洁作用。在9～13％低水温期亦会摄食与生长。适温下限在7．2℃以下，适温上限在25．6℃以下。养殖方式以混养为宜，生产安排以10月份收购502左右的苗种养至翌年6月达100g以上规格出售为好，该养殖模式能避开台风期与高温期。褐鲉鲇肉质细嫩，味道鲜美，近年颇受人们欢迎，其经济价值高，且我国沿海褐菖鲇苗种资源丰富，养殖开发前景良好。 相似文献
2.
为研究鲈鲤(Percocypris pingi)苗种的生长特性,开发鲈鲤育苗技术,采用水泥池流水单养模式,在自然水温条件下,开展了10日龄至110日龄鲈鲤苗种培育试验。经过100 d的培育,鲈鲤鱼苗体质量从(46.45±4.03)mg增加到(2600.09±105.18)mg,平均体长从(16.22±0.46)mm增长到(50.78±2.97)mm,平均成活率为82.00%;体质量变异系数在4.05%~24.80%,体长变异系数在2.49%~7.32%,体质量变异系数大于体长变异系数;体质量变异系数整体呈现先升高后降低的变化趋势,体长变异系数整体变化较为平缓,在整个培育阶段,鲈鲤种群生长离散呈现从加剧到减弱的变化规律;体质量特定生长率在(0.91±0.49)%/d~(7.75±2.18)%/d,体长特定生长率在(0.47±0.29)%/d~(1.94±1.46)%/d,体质量特定生长率大于体长特定生长率;在水温16.8~23.0℃条件下,鲈鲤生长状况良好,特定生长率相对较高,当水温高于23.0℃之后,特定生长率呈降低趋势,表明16.8~23.0℃是鲈鲤鱼苗适宜的生长水温范围;肥满度变化范围在(1.09±0.10)~(2.85±0.18)g/cm^3,肥满度变化呈现先升高后降低的变化趋势;体长(x)和体质量(y)的拟合方程为y=0.0015x^3.7566(R^2=0.9806),b值为3.7566;全长(y)和体长(x)的拟合方程为y=1.223x-0.5055(R^2=0.9908)。试验结果表明,鲈鲤苗种在水泥池流水单养模式及自然水温条件下生长状况良好,16.8~23.0℃是鲈鲤苗种的适宜生长水温。 相似文献
3.
断斑石鲈卵和仔鱼的发育 总被引：5，自引：0，他引：5
断斑石鲈是一种近海浅水底栖鱼类,个体较大,生长也快,可选做为发展近海增养殖的鱼种之一。本文通过人工授精方法,对鱼卵及仔鱼的发育做了观察,在水温23.7—25.00℃的海水中培养,受精卵经过约20个小时,可全部孵出仔鱼。并与三线矶鲈的卵和仔鱼发育的特征作了比较,以便在早期发育阶段采苗育种时做为参考依据。 相似文献
4.
5.
6.
本文是从1963年4月25日至同年5月25日,在海南岛儋县洋浦湾用52GG筛绢制成的卫生鱼卵网拖取鱼卵标本16次,其中有5次是在晚7～9点;一次在中午,其余10次都是在上午7时30分～10时。 现将整理出的8种,内隶属鲱科 Clupeidae的 4种即脂眼鲱 Etrumenus micropus、玉鳞角Kowala coval、斑鰶Clupanodon punctatus、无齿鰶 Anodontoma chacunda;鱚科Sillagidae 的多鳞鱚 Sillago sihama;裸颊鲷科 Lethrinidae 的线棘裸颊鲷 Lethrinus nematacanthus;石鲈科 Pomadasyidae的三线矶鲈,paraprisipoma trilineatum;(鱼衔)科Callionymidae的一种Callionymus sp。 就该8种鱼卵、仔鱼拖到的时间及当时水温、盐度和孵化时间等归纳以下几个问题: (1)这些鱼类的卵及其仔鱼除三线矶鲈外,其他7种在本海区尚属第一次报道。 (2)该8种鱼卵均属圆球形,无色透明,彼此分离,天然受精卵浮于水面。在发育过程中有色素胞出现,脂眼鲱、玉鳞鱼、斑鰶、无齿鰶和三线矶鲈的卵黄有泡沫状龟裂,而(鱼衔)属的一种卵膜具有整齐的六角形龟裂纹(卵径0.61～0.68毫米),是其主要特征,与其他7种卵子极易区别。在16次采样中,它们分布在水温28～30℃、盐度30.70～31.62％之间。 (3)它们在湾内的产卵期均在4～5月前后,根据卵内的发育时间推测,其放卵时间均应 相似文献
7.
最近,浙江南麂岛海洋投资公司又在南麂岛海域的人工鱼礁区增殖放流了大黄鱼、黑鲷、真鲷、花尾胡椒鲷等珍贵海水鱼类的苗种150万尾.迄今为止,该公司累计放流体长在5cm以上的鱼种500万尾,成为国内民营企业向大海放流鱼类苗种最多的单位. 相似文献
8.
本文就2005~2006年从山东引进的半滑舌鳎苗种的养殖概况进行了总结。半滑舌鳎苗种在工厂化条件下,养殖水温16.7℃~27℃,盐度20~25,经9个月养殖雌鱼体重可达500g,养殖15个月时,雌鱼体重可达1500g,雄鱼体重约300~500g。2005年引入的苗种总体成活率达99.6%,2006年引进的苗种养殖成活率为89.8%。购入的全长8~16cm,体重3~20g的半滑舌鳎苗种,经15个月的养殖可达到第一次性成熟。另外,探讨了水温对半滑舌鳎生长的影响和以防为主的疾病防治技术,并对半滑舌鳎全雌鱼养殖及国产化优质配合饲料的生产等方面作了初步的讨论。 相似文献
9.
本文就2005-2006年从山东引进的半滑舌鳎苗种的养殖概况进行了总结。半滑舌鳎苗种在工厂化条件下,养殖水温16.7℃-27℃,盐度20-25,经9个月养殖雌鱼体重可达500g,养殖15个月时,雌鱼体重可达1500g,雄鱼体重约300-500g。2005年引入的苗种总体成活率达99.6%,2006年引进的苗种养殖成活率为89.8%。购入的全长8-16cm,体重3-20g的半滑舌鳎苗种,经15个月的养殖可达到第一次性成熟。另外,探讨了水温对半滑舌鳎生长的影响和以防为主的疾病防治技术,并对半滑舌鳎全雌鱼养殖及国产化优质配合饲料的生产等方面作了初步的讨论。 相似文献
10.
根据海洋调查规范,对围网敷设海域温州平阳南麂岛海域的水文条件、海域情况进行了调查和监测,并以水文条件为参考,分析了大潮差条件下的防网衣纠缠技术、水流和波浪条件下的防逃贴底技术与抗风浪技术,以期为给浅海围网养殖技术的完善和推广提供理论依据.监测结果:调查海域的水温变化范围为10.3～29.5℃;盐度垂向分布总体较均匀,变化范围为27.63 ～33.91;营养盐比较丰富,水色以绿至浅蓝为主,透明度一般大于2 m;水流速度小于1 m·s-1,最大潮差6.13 m,波浪以0～3级为主.结果表明,温州平阳南麂岛海域适合开展大黄鱼浅海围网养殖. 相似文献
11.
Association between the interannual variation in the oceanic environment and catch rates of bigeye tuna (Thunnus obesus) in the Atlantic Ocean 
下载免费PDF全文
下载免费PDF全文 The environmental processes associated with variability in the catch rates of bigeye tuna in the Atlantic Ocean are largely unexplored. This study used generalized additive models (GAMs) fitted to Taiwanese longline fishery data from 1990 to 2009 and investigated the association between environmental variables and catch rates to identify the processes influencing bigeye tuna distribution in the Atlantic Ocean. The present findings reveal that the year (temporal factor), latitude and longitude (spatial factors), and major regular longline target species of albacore catches are significant for the standardization of bigeye tuna catch rates in the Atlantic Ocean. The standardized catch rates and distribution of bigeye tuna were found to be related to environmental and climatic variation. The model selection processes showed that the selected GAMs explained 70% of the cumulative deviance in the entire Atlantic Ocean. Regarding environmental factors, the depth of the 20 degree isotherm (D20) substantially contributed to the explained deviance; other important factors were sea surface temperature (SST) and sea surface height deviation (SSHD). The potential fishing grounds were observed with SSTs of 22–28°C, a D20 shallower than 150 m and negative SSHDs in the Atlantic Ocean. The higher predicted catch rates were increased in the positive northern tropical Atlantic and negative North Atlantic Oscillation events with a higher SST and shallow D20, suggesting that climatic oscillations affect the population abundance and distribution of bigeye tuna. 相似文献
12.
13.
In this experiment, a feeding trial was performed to determine the effects of fructooligosaccharide (FOS) on growth performance, digestive enzyme activity and immune response of Japanese sea bass, Lateolabrax japonicus juveniles (initial weight 38.3 ± 0.5 g), and the fish were examined following feeding with six levels of FOS (0, 0.5, 1, 2, 4 and 6 g/kg) for 28 days. Significant enhancement of weight gain (WG) and specific growth rate (SGR) was found in fish fed 1 g/kg FOS incorporated diets (p < .05), while the feed conversion ratio (FCR) in the 1, 2 g/kg FOS groups reduced significantly compared with the control (p < .05). Besides, the crude lipid in the 4, 6 g/kg FOS groups increased significantly compared with the control (p < .05). On the other hand, the erepsin and lipase activities significantly elevated in intestine of fish fed 2 g/kg FOS (p < .05) and the lysozyme activity in serum of fish fed 2 g/kg FOS were significantly higher than that in the control (p < .05). Moreover, the alkaline phosphatase activities in serum of fish fed 0.5, 1, 2 g/kg FOS were significantly higher than in control (p < .05). Regression analysis showed that the relationships between dietary FOS levels and either SGR, FCR, erepsin or lysozyme activities were best expressed by regression equations, and the optimal inclusion levels are 1.37, 1.80, 3.06, 3.11, 1.93 and 1.80 g/kg for SGR, FCR, erepsin, lipase, lysozyme and total superoxide dismutase activities, respectively. Overall, this study revealed that FOS incorporated diets could beneficial for L. japonicus culture in terms of increasing the growth, digestion and immune activities. Under the present experimental condition, the optimal supplementary level of FOS in the diet of L. japonicus is 1–3 g/kg. 相似文献
14.
Liping Li Rui Wang Wanwen Liang Xi Gan Ting Huang Yan Huang Jian Li Yunliang Shi Honglin Luo Ming Chen 《广西水产科技》2014,(1)
Previously, we reported 10 PEGE types of 85 tilapia Streptococcus agalactiae(GBS), which shifted from Streptococcus iniae in China, by using PEGE method. Presently, larger and more representative tilapia GBS were isolated, for the ?rst time in China, to characterize their serotypes and genetic diversities more precisely than had done before. 168 GBS strains were distributed in ?ve provinces of China, in which Guangdong, Guangxi and Hainan were the major ones, holding36.9%(62/168), 37.5%(63/168) and 19.6%(33/168), respectively. Serotypes, Ia, Ib and III, were observed in these strains and the most predominant one was Ia(95.2%), which mainly distributed in Guangdong, Guangxi and Hainan. Ia initially occurred in 2009, it shoot up to 32.1% in 2010,but decreased to 16.1% in 2011 before went up to 45.2% in 2012. Ib sporadically occurred during2007–2011, III onlyoccurred in 2012. 14 different PFGE types, including 4 new types(N, O,P and Q), were observed, in which B, D, F and G were the predominant types, holding 83.9%(141/168) of the total GBS strains. Ia corresponded to 11 PFGE types(A–H, N–P), in which type D predominated(51%). Ib represented 3 genotypes(I, J and Q) and III harbored only 2genotypes(N and F). Type N and Fsynchronously presented in Ia and III. In summary, the genetic diversity of tilapia GBS varied by serotypes and changed with geographical locations and years.Although Iastillpredominated, new rareserotypeIII alreadyoccurred in China. 相似文献
15.
16.
Iciar Martinez Amaya Velasco Ricardo Pérez-Martín Eskil Forås Michiaki Yamashita Carmen G. Sotelo 《Journal Of Aquatic Food Product Technology》2013,22(4):289-297
The purpose of this work was to evaluate the suitability of a method based on the presence of two restriction sites (for Hae III and Hindf I) in the mitochondrial NADH dehydrogenase subunit 5 (mt ND5) gene to identify Scomber species. The evaluation was performed on 144 reference and market samples by sequencing of the entire 505-bp fragment of the mt ND5 gene and of a 464-bp fragment of the Kocher fragment of the cytochrome b gene (mt Cytb). Sequence analysis of any of the two fragments allows the identification of each of the four Scomber species, but S. japonicus and S. colias had the same restriction sites at the ND5 amplicon and would not have been differentiated by this analysis. Similarly, loss of the Hae III site in some S. scombrus individuals would have misidentified them as not being Scomber. All the market products were correctly labeled except one acquired in Spain labeled as originating in the Atlantic and containing S. japonicus. 相似文献
17.
Growth hormone (GH) and reproduction: a review 总被引：5，自引：0，他引：5
Florence Le Gac Odile Blaise Alex Fostier Pierre-Yves Le Bail Maurice Loir Brigitte Mourot Claudine Weil 《Fish physiology and biochemistry》1993,11(1-6):219-232
Interaction between growth and reproduction occurs in many vertebrates and is particularly obvious at certain stages of the life cycle in fish. Endocrine interactions between the gonadotropic axis and the somatotropic axis are described, the potential role of GH being emphasised. A comparative analysis of these phenomena in mammals, amphibians and fish, suggests a specific role of GH in the physiology of puberty, gametogenesis and fertility. It also shows the original contribution made by studies on the fish model in this field of investigations. 相似文献
18.
Two gonadotropins (GtH; Qa and Qb) were purified by gel filtration and ion exchange chromatography from the pituitaries of Indian walking catfish (Clarias batrachus). The presence of GtH during purification was assessed by in vitro oocyte maturation and in vivo steroidogenic activity, and their identities were determined by elution profiles, molecular weight, biological activities and yield. The molecular weights of Qa and Qb were 37 and 42 kDa, respectively, and composed of distinct subunits (Qa: 20 and 14 kDa and Qb: 26 and 18 kDa). Polyclonal antibodies raised against Qa immunostained Qa, Qb and pituitary GtH cells. A competitive Qa‐ELISA was developed whose sensitivity was 6.25 ng mL?1 (1.25 ng well?1) with intra‐ (3.5%) and inter‐ (12.4%) assay coefficients of variation. Displacement curves parallel to the standard were obtained with plasma and pituitary extracts of catfish, Qb and carp GtHII. The assay was validated by measuring the plasma Qa levels after LHRH treatment and in relation to ovarian growth in the female catfish during different reproductive phases. Based on the results, Qa and Qb corresponded to fish LH and FSH respectively. The findings will increase the knowledge of the mechanisms controlling fish reproduction and identification of sensitive phases in fish in captivity for hormonal manipulation. 相似文献
19.
20.
Qin-Cheng Huang Di‐Gen Qin Bei‐Ping Tan Tao Du Yuan-Zhi Yang Qi-hui Yang Shu‐Yan Chi Xiao-hui Dong 《Aquaculture Research》2020,51(2):816-827
A 5 × 3 factorial growth trial was conducted to evaluate optimal dietary protein and lipid levels (dietary protein level, DP; dietary lipid level, DL) for juvenile Sillago sihama (S. sihama) (2.0 ± 0.02 g, initial weight). Fish were fed 15 diets containing 5 DPs (350, 400, 450, 500 and 550 g/kg) and 3 DLs (60, 90 and 120 g/kg) for 8 weeks. The interaction between proteins and lipids significantly influenced the feed conversion ratio, condition factor, body composition, antioxidant indices and lipase activity (p < .05). DP 450 g/kg showed the highest average final body weight. DPs 500 and 550 g/kg significantly decreased the protein efficiency ratio (p < .05). DL 120 g/kg showed the highest percentage weight gain. The low feed conversion ratio was found in diets P45L12, P55L9 and P55L12. Diet P45L12 showed high superoxide dismutase activities. DP 450 g/kg showed the lowest average malondialdehyde content. Lipase activity was increased by increasing DP (p < .05) with a fall at DP 550 g/kg. Under the present experimental conditions, the optimal DP for S. sihama was 450 g/kg under the DL 120 g/kg. 相似文献