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1.
This study tested different tags for each size of farm-reared gilthead sea bream, Sparus aurata L. juveniles, used in enhancement programmes. The following tags were tested: dye mark, fingerling tag, opercular tag, anchor tag A (filament diameter of 1.20 mm) and anchor tag B (0.85 mm). Tag/mark retention, wounds produced by the tag, ease of application, ease of detection and cost were examined. Epidermal dye marks had poor retention and detection rates. Of the tags tested, retention was greater for the anchor tag A (80–100%) after 7 months; anchor tag B showed a retention rate of only 20% after 3 months. The fingerling tag had a retention rate of 27.5% after 12 months. The opercular tag had a retention rate of 44% after 20 days but fractured the opercular bone in many cases. Tag incisions and wounds persisted in some fish for the duration of the experiment.  相似文献   
2.
乌鳢苗种繁育及池塘高产养殖技术   总被引:1,自引:0,他引:1  
为探讨乌鳢的人工养殖技术,对乌鳢苗种繁育及池塘养殖阶段的关键环节:亲鱼培育、人工催产、鱼卵孵化、鱼种培育、成鱼养殖等进行了系统研究。并总结了一套实用的乌鳢养殖技术。实践证明,使用该技术能提高乌鳢鱼苗成活率和成鱼产量。  相似文献   
3.
黄颡鱼的生物学特性与养殖技术   总被引:6,自引:0,他引:6  
通过对黄颡鱼的生物学特性、繁殖技术、苗种培育技术、养殖技术、放养模式、病害防治技术的系统研究,探明了黄颡鱼的食性、溶氧需求、温度适应性、盐度耐受性等生物学特性,报道了黄颡鱼繁殖与苗种培育措施,提出池塘养殖所需配套技术及常见病害防治技术。  相似文献   
4.
ABSTRACT:   Three diets supplemented with taurine, β-alanine andGABA and a control diet were fed to juvenile and fingerling Japaneseflounder to investigate the effects of the diets on growth and metabolicchanges of free amino acids in whole body and tissues. In experimentI, three diets supplemented with 1% each of taurine, β-alanineand GABA and a control diet were fed to juvenile Japanese flounderwith an initial mean body weight of 0.4 g for 4 weeks at20°C. In experiment II, the taurine-supplemented diet anda control diet were fed to fingerling Japanese flounder with an initialmean body weight of 15 g for 4 weeks at 20°C.Only supplementation of taurine in the diet of juvenile flounderimproved their growth performance in experiment I, but fingerlinggrowth performance of experiment II was not significantly relatedto taurine supplementation in the experimental diet. These resultssuggest that there is a greater requirement for taurine for thegrowth of juvenile Japanese flounder than fingerling Japanese flounder.  相似文献   
5.
    
Hybrid striped bass fingerlings were grown in replicated indoor tanks for 42 days to evaluate progeny performance of two growth-related traits. Analysis of variance demonstrated significant differences in length and weight of fingerlings among paternal and maternal half-sib families and high estimates of heritability for dams and sires. Based on significant sire and dam effects and high heritabilities, a substantial portion of the selection differential could be expected to be gained in offspring from selected pure-line parents. As demonstrated by these results, a breeding program could be used to select parental lines that produce faster growing hybrid offspring.  相似文献   
6.
本文从病理组织学的角度,研究了罗非鱼鱼种肠炎病的发生与发展,为其诊断与防治奠定了理论基础。结果表明,该病病原体为产气单胞菌。  相似文献   
7.
本文对草鱼、鲢、鳙、团头鲂4种养殖鱼类在鱼苗期、1龄期、2龄期的RNA和DNA含量进行测定.结果指出RNA/DNA的变化规律与鱼类的生长情况一致,因此,RNA/DNA可以怍为评定这4种养殖鱼类在鱼种阶段生长的指标。  相似文献   
8.
[目的]降低草鱼池塘养殖生产成本,提高池塘水体利用率和综合养殖效益,增强养殖模式的抗风险能力以及示范推广作用.[方法]在江苏省宿迁市宿城区中扬镇开展了草苗种、泥鳅池塘双主养模式养殖试验.[结果]放养260尾/kg的泥鳅苗种180 000尾/hm2,放养2 000尾/kg的草苗种60 000尾/hm2的养殖模式,以及放养260尾/kg的泥鳅苗种120 000尾/hm2,放养2 000尾/kg的草苗种75 000尾/hm2的养殖模式,产出投入比均较高.[结论]放养260尾/kg的泥鳅苗种120 000尾/hm2,放养2 000尾/kg的草苗种75 000尾/hm2的养殖模式更容易被养殖者接受,更容易被大面积推广应用.  相似文献   
9.
池塘面积1067m^3,主养彭泽鲫鱼种,搭配团头鲂及鲢鳙鱼种,经156天饲养,共产鱼1029.6kg,折合667m^2产鱼643.5kg。其中每667m^2产彭泽鲫鱼种367.8kg,平均规格70g。每667m^2利润3498元。投入产出比为1:1.67。  相似文献   
10.
Since the demand of African Catfish (Clarias gariepinus) is on increase there is need to increase its production so as to meet the protein requirement of the populace. An investigation was conducted for six weeks feeding trial to determine the performance of African catfish (Clarias gariepinus) fingerlings feed diets containing varying replacement level of fish meal with pawpaw seed powder meal (Carica papaya). Fingerlings of Clarias gariepinus were subjected to five different dietary treatments with varying levels of pawpaw seed powder meal. The diets I-V contained 0, 20%, 40%, 60% and 80% replacement levels, respectively. The experiment was carried out in an 80 litres circular plastic bowls, the treatments were in triplicate. Each bowl contained 12 fingerlings. Feeding was done at 3% body weight per day and fishes were weighed every week. Growth parameters such as specific growth rate (SGR), weight gained (WG), food conversion ratio (FCR), protein efficiency ratio (PER) and mortality were determined. Therefore, it could be concluded that fish meal could be replaced up to 80% with pawpaw seed powder meal in the diet of Clarias gariepinus fingerlings to encourage growth, while at 40% pawpaw seed powder meal inclusion mortality was reduced.  相似文献   
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