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91.
水温 饵料 投饵率对河蟹生长和饵料转化率的影响 总被引:3,自引:0,他引:3
在实验室条件下研究了水温、饵料和投饵率对河蟹生长的影响。结果表明,在10~26℃水温范围内,河蟹对不同饵料的摄饵率和特定生长率均与水温呈正相关关系;相比之下,用配饵投喂,河蟹对温度的变化较为敏感,但配饵的饲养效果明显次于螺蛳。随着水温的升高,当螺蛳的投饵率由半饱增至全饱时,河蟹的湿重生长率增长不明显,而体蛋白量则增加了13%~28%。在适温范围内,适当降低投饵率可提高饵料转化率和蛋白质利用率,可是蟹体蛋白量的增加则明显下降。 相似文献
92.
The effects of different diets (natural or pellets) on growth, survival, and moulting interval of juvenile spider crabs, weighing
between 0.011–1.56 g and up to 17.6 mm in carapace length, were tested over a period of 90 days. During experiment I, five
diets were tested: (1) frozen shrimp—Paleomonetes sp., (2) fresh mussels—Mytilus sp., (3) white fish fillets—Merlucius merlucius, (4) blue fish fillets—Sardina pilchardus, and (5) commercial crustacean pellets. Spider crabs fed fresh mussels grew larger (0.98 ± 0.69 g) and had higher growth
rates (4.0 ± 0.7 %BWd−1) compared to the other four diets. The crabs fed shrimp pellet and frozen shrimp grew to intermediate sizes and were smaller
than the ones fed fresh mussels, but they were larger than spider crabs fed either blue or white fish fillets (0.46 ± 0.63
and 0.26 ± 0.13 g, respectively) compared to the ones fed white fish fillets (0.12 ± 0.04) and blue fish fillets (0.04 ± 0.02 g).
The spider crabs fed blue fish fillets only lasted until day 60 of the experiment, after this day none of the 20 fed this
diet were left. During experiment II, two diets were tested: (1) white and blue fish fillets and (2) commercial fish pellet.
There were no differences in growth both in weight or carapace length (2.9 ± 1.8 and 2.1 ± 1.5 g in weight, and 18.9 ± 5.0
and 17.7 ± 3.3 mm, respectively) at the end of the experiment. Similarly, there were no differences in growth rates in weight
between the two diets (1.2 ± 0.4 and 0.9 ± 0.3 %BWd−1, respectively) or in carapace length (0.4 ± 0.1 and 0.4 ± 0.2 %BWd−1, respectively). Fresh mussel appears to be a very good diet to culture the early stages of this species, while shrimp pellets
also deliver acceptable results. On the contrary, frozen shrimp, fish fillets either from blue or white species (much higher
lipid content in the blue species), and fish pellets were found to be bad diets for the culture of the early stages of M. brachydactyla. 相似文献
93.
在解剖、测量性成熟和未成熟中华绒螯蟹外部形态和性腺之基础上,试用“双百分率法”和“差异显著性检测法”对中华绒螯蟹的副性征进行了研究。结果表明,性成熟后的雌、雄中华绒螯蟹均具有较明显的副性征。 相似文献
94.
95.
Daily food intakes, optimal feeding regimes and food concentrations for laboratory reared Paralithodes camtschaticus (Tilesius, 1815) larvae were investigated. Artemia nauplii hatched at standard conditions were used as food. Daily food intakes of zoeae I–IV at 7–8 °C comprised 11.3, 22.4, 33.2, and 41.8 nauplii individuals (ind)?1 day?1, respectively, taking into account that wet weight of Artemia nauplii used for the experiments constituted 0.026 mg, dry weight 0.0042 mg. Optimal initial Artemia nauplii concentrations for feeding zoeae I–IV was determined as 400–600, 600–800, 800–1000 and 1000–1200 nauplii L?1 respectively. Recommendations on using Artemia nauplii as food for red king crab larvae were outlined on the basis of experimental results. Growth, development and survival rates of zoeae I–IV reared in recycling water system at 7–8 °C and fed Artemia nauplii according to these recommendations were described. 相似文献
96.
Veronica R Alava Emilia T Quinitio Jennete B de Pedro Flora Mae P Priolo Zenith Gaye A Orozco & Mathieu Wille 《Aquaculture Research》2007,38(14):1468-1477
Wild‐caught and pond‐reared female mud crab Scylla serrata at different stages of ovarian maturation were collected from Samar and Capiz, Philippines. Crabs were categorized into five stages according to the external morphological and microscopic appearance of the most advanced oocytes. The ovaries, hepatopancreas, muscle and newly spawned eggs (NSE) were analysed for lipid class components and fatty acids. Total lipid was higher in pond‐reared than in wild‐caught crabs but increased with ovarian maturation in both groups. Ovarian lipid peaked at the fully mature stage, coinciding with a decline in hepatopancreatic and muscle lipids. Lipid levels declined significantly in spent females. The tissues contained elevated highly unsaturated fatty acids such as arachidonic (20:4n‐6), eicosapentaenoic (20:5n‐3) and docosahexaenoic (22:6n‐3) acids, but at higher levels in late maturing and fully mature ovaries and in NSE. The type of lipid class and fatty acid components in mature ovaries as well as in NSE are generally considered to be indicative of their importance in reproductive physiology and embryonic and larval development. 相似文献
97.
Wang?Gui-zhongEmail author Li?Shao-jing Zeng?Chao-shu Lin?Shu-jun Kong?Xiang-hui Ai?Chun-xiang Lin?Qiong-wu 《Aquaculture International》2005,13(5):459-468
This is an initial paper in a series of overviews of biological research and aquaculture development of the mud crab, Scylla serrata, in China. Results of experimental ecological studies on mud crabs are reported here. As a result of these experimental studies, results that are important for mud crab culture were also discovered and these include, methods to condition and manage broodstock, determination of ecological conditions that are suitable for embryonic development, and the influence of temperature, salinity, diet and larval density on development and survival of larvae. Results of this work will be useful in establishing a good method for artificial mass culture of larvae. 相似文献
98.
99.
从池塘修建、河蟹放养规格、时间、密度、生产管理和疾病防治等方面探讨了宁夏银川地区池塘养殖河蟹技术,试验养殖的河蟹产量达6 393.0 kg/hm2、平均135.3 g/只,经济效益达18 840元/hm2,具有较好的开发前景。 相似文献
100.
长江野生中华绒螯蟹育苗性能的初步研究 总被引:1,自引:0,他引:1
2011年11月,从安徽省无为县选择野生长江中华绒螯蟹亲本1 388只,到江苏省如东县进行天然海水生态育苗,其中雄蟹350只,总重80.05 kg;雌蟹1 038只,总重194.05 kg。在面积为2.5亩的池塘中,进行对比育苗试验,繁育盐度保持在19‰~26‰,pH变化范围在8.28~8.90,比较野生长江中华绒螯蟹与普通蟹之间繁育性状的差异。结果表明,野生亲本的体重和卵重均高于普通亲本,差异极显著;野生亲本与普通亲本的成熟系数和相对繁殖力差异不显著;野生蟹产卵率(52.85%)高于普通蟹产卵率(30.91%);野生蟹亲本组幼体发育较普通幼体发育为快,幼体个体较大,共产大眼幼体苗6.5 kg,大眼幼体规格137 848个.kg-1,平均125.3只.g-1;普通亲本组大眼幼体共产23 kg,规格为156 468个.kg-1,平均156.5只.g-1。 相似文献