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稻蟹共生系统河蟹放养密度对水稻和河蟹的影响 总被引:1,自引:0,他引:1
采用稻田陆基围隔方法,研究了成蟹放养密度对水稻产量、河蟹生长以及产量的影响,并对稻田放养不同密度的河蟹进行了经济效益分析。结果表明,河蟹的放养密度对稻田土壤化学指标影响不显著(P0.05);河蟹的放养密度对河蟹的产量影响极显著(P0.01);放养不同密度河蟹对水稻产量影响不显著(P0.05);经济效益分析的结果表明,0.75只/m2稻田养蟹的净利润最高,而其他各组差异显著(P0.05)。稻田养殖成蟹的最佳放养密度为0.75只/m2左右。 相似文献
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黄颡鱼健康养殖放养密度试验 总被引:1,自引:1,他引:0
对黄颡鱼池塘养殖进行不同放养密度效果的对比试验,结果表明:在普通养鱼池塘,放养平均规格22.7g/尾的黄颡鱼冬片鱼种,放养密度以4.5万尾/hm2为宜,此时,黄颡鱼养殖成活率80%以上,平均出池规格150g/尾以上,池塘养殖平均产量4 500kg/hm2以上。 相似文献
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为研究中华绒螯蟹(Eriocheir sinensis)幼蟹生长和蜕壳与有效积温的关系,在河蟹生态养殖池塘中放置网箱养殖中华绒螯蟹;温度记录仪探头入水深度为20 cm,且每周清理一次,每次记录时间间隔为20 min,每天至少早晚各查看一次。每口网箱放养中华绒螯蟹大眼幼体500只,以水花生为隐蔽物,保持生长环境尽量相同且适宜生长。经过158 d的养殖,幼蟹蜕壳11次长成蟹种,平均成活率为28.43%±4.61%,平均水温为(24.4±0.05)℃,总有效积温为(3 040.4±244.16)℃·d,且随着中华绒螯蟹蜕壳,有效积温增长趋势最接近指数函数y=40.942e0.2655x(R2=0.9904),累计有效积温增长趋势最接近多项式y=33.336x~2-115.05x+196.14(R2=0.997 8);特定生长率随有效积温的变化曲线最接近幂指数增长关系y=20.926e-0.005x(R2=0.933 3);累计有效积温对壳长、壳宽、体高的相关性极为显著,壳长、壳宽、体高随累计有效积温的增长均呈幂指数增长关系。 相似文献
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2012—2013年,在安徽蓝田特种龟鳖有限公司采用龟二级快速养殖方式养殖乌龟,将当年繁殖的稚龟进行温室培育,1年后进行室外池塘生态养殖,结果表明:当年繁殖的体重5 g左右的稚龟,温室放养密度100只/m2,经过12个月温室培育,出池规格达到350 g左右,成活率82.51%;室外池塘生态养殖池面积0.33 hm2,放养密度1.5万只/hm2,10月底起捕上市,成活率94.56%。平均规格550 g/只,销售乌龟2 600.4 kg,价格110元/kg,收入286 044元,生产成本125 000元,实现利润161 044元,平均483 132元/hm2。 相似文献
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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
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对传统河蟹池塘主养模式和藕-蟹-鱼生态养殖模式的养殖结果及水体营养状况进行了评价.结果表明,河蟹主养模式河蟹平均规格为102 g/只,经济效益为33 750元/hm2,投入产出比为1∶2.12,藕-蟹-鱼套养模式河蟹平均规格为133g/只,经济效益为56 350元/hm2,投入产出比为1∶3.94,藕-蟹-鱼套养模式比河蟹主养模式经济效益增加22 600 元/hm2,经济效益提高66.96%;河蟹主养模式池塘6、7、8月份水体为中度富营养类型,藕-蟹-鱼生态养殖模式池塘水体6月份为中营养类型,7、8月份为轻度富营养类型,总体而言,藕-蟹-鱼生态养殖模式池塘水体营养状况均好于传统的河蟹主养池塘2~3个数号级. 相似文献
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《农业科学与技术》2016,(3)
A total of 15 pools were selected from a greenhouse, and they were randomly and evenly divided into three groups. In each group, one stocking density of Eriocheir sinensis was arranged. The results showed that after 45-d culture, the crab number per kilogram reached about 300 with survival rate of about 20%; the initial stocking density had significantly effect on the body size of E. sinensis on sel , instead on the survival rate of E. sinensis larvae. Therefore, it is feasible to conduct the culture of E. sinensis larvae in a pool in greenhouse. 相似文献
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为探究辽河和长江水系及其杂交种中华绒螯蟹在成蟹阶段的生长性能和养殖效果差异,在相似的池塘条件下将辽河和长江水系及其杂交种扣蟹养殖至成蟹。本文系统地比较了在养殖过程中的生长、生殖蜕壳率和性腺发育情况,进一步评价了成活率、产量、饲料系数和最终体质量分布等差异。结果表明:(1)在生长阶段,四组中华绒螯蟹平均体质量、增重率(WGR)和特定生长率(SGR)均无显著性差异(P> 0.05)。雌体生殖蜕壳高峰出现在7月25日到8月25日,雄体生殖蜕壳高峰则出现在8月25日到9月25日。人工养殖辽河水系成蟹生殖蜕壳时间与长江水系成蟹基本一致,并无二龄早熟性状。9~11月,雌雄个体的肝胰腺指数(HSI)逐渐下降,性腺指数(GSI)显著上升。(2)四组中华绒螯蟹在成活率、产量和饲料系数等方面存在显著性差异(P< 0.05)。最终养成成蟹雌体体质量集中于100.00~175.00 g,雄体体质量集中于175.00~225.00 g。综上,长江与辽河水系杂交组生长性能与自交组并无显著性差异(P> 0.05),辽河水系中华绒螯蟹在长江流域经适应性养殖后,生长性能得以提高,二龄早熟性状消失,而以长江水系中华绒螯蟹作为母本的杂交种则成活率和产量杂种优势明显。 相似文献
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为了对从国外引进的Kona Bay、OI、SIS和环球4种品系凡纳滨对虾Litopenaeus vannamei 1代虾苗的养殖效果进行评估,分别在150、300尾/m2两种养殖密度下进行56 d的养殖试验,对各品系的养殖参数,包括存活率、总增重、特定生长率、饵料系数、体质量变异系数进行分析。结果表明:两种养殖密度下,Kona Bay品系综合养殖效果最好,低、高养殖密度养殖皆宜;环球品系与OI品系在高养殖密度条件下的存活率显著低于低养殖密度条件下(P0.05),且养殖密度增加对其总增重影响不明显(P0.05),OI品系甚至出现负增长,表明两者不适合高密度养殖;高养殖密度对SIS品系成活率、总增重、饵料系数影响均不显著(P0.05),但高养殖密度有利于其养殖后质量变异系数的降低,SIS品系比较适合高密度养殖。 相似文献
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为了探索盐碱地稻蟹种养中河蟹适宜的放养密度,在黄河口盐碱地进行为期180天的稻蟹共作试验(雌蟹:雄蟹=1:1),研究了不同放养密度(1.5 inds/m2、0.75 inds/m2和0.38 inds/m2,分别记为D150,D075,D038组)对河蟹生长和养殖性能、可食组织系数、生化组成、生理代谢、饵料贡献和经济效益的影响。结果显示:(1)随着养殖密度的降低,河蟹的增重率、特定生长率和成活率显著升高,而产量和饵料系数显著降低(P < 0.05)。(2)各密度组的河蟹可食组织系数和总可食率无显著差异。(3)随着养殖密度降低,雌、雄蟹肌肉中粗蛋白含量显著降低,而雌蟹的肝胰腺总脂肪含量显著增加(P < 0.05)。(4)就生理指标而言,雌蟹肝胰腺中碱性磷酸酶(ALP)、酸性磷酸酶(ACP)活力随养殖密度降低而显著升高,而血清中总抗氧化能力(T-AOC)和丙二醛(MDA)含量呈显著下降趋势;类似地,雄蟹肝胰腺中ALP活力在D038组最高(P < 0.05),而肝胰腺中MDA含量和血清中T-AOC显著降低,在D038组最低(P < 0.05)。(5)不同放养密度下河蟹的第一食物来源均为饲料(39.39 % ~ 52.33 %),且随养殖密度的降低,食源中饲料占比呈上升趋势,而食源种本底蟹占比呈下降趋势。(6)各组的部分总收入和部分总利润无显著差异,D038组的投资回报率显著高于其他密度组。综上所述,虽高密度组获得最高的产量和收入,但低放养密度组的河蟹取得最佳的生长性能和健康状况,且利润和投资回报率最高。因此,在本实验条件下,黄河口盐碱地的稻蟹模式中河蟹适宜的放养密度为0.38inds/m2。 相似文献
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《农业科学与技术》2016,(5):1238-1242
The Chinese soft-shel ed turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China. This study in-vestigated the effects of stocking density on water quality, growth performance and economic return of Pelodiscus sinensis cul-tured in ponds. P. sinensis were stocked at densities of 1 ind./m2 (LD: low stocking density) and 2 ind./m2 (HD: high stocking density) in 3 000-m2 ponds, with three replicate ponds for each density. P. sinensis juveniles were fed with a commercial dry pel et feed of 46% crude protein and minced fil et of silver carp ans cultured for 122 days. The results showed that the levels of total nitrogen (TN), total phosphorous (TP), Chlorophyl-a (Chl. a) and turbidity in LD treatment were significantly lower than those in HD treatment (P<0.05). The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment, respectively. Mean survival rates, final weight, average growth rates and PER were significantly higher in LD treatment compared with the HD treatment (P<0.05), respectively. Production was significantly af-fected by stocking density, which was higher in HD treatment, but the net income was higher in LD treatment. The results sug-gest that turtles with mean weight 55.6 g rearing at a low stocking density (1 ind./m2) in ponds had a positive effect on overal economic return and was effective at improving turtle growth performance and water quality. 相似文献
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《(《农业科学与技术》)编辑部》2016,(5)
The Chinese soft-shelled turtle Pelodiscus sinensis is a high-valued freshwater species cultured in China.This study investigated the effects of stocking density on water quality,growth performance and economic return of Pelodiscus sinensis cultured in ponds.P.sinensis were stocked at densities of 1 ind./m~2(LD:low stocking density) and 2 ind./m~2(HD:high stocking density) in 3 000-m~2 ponds,with three replicate ponds for each density.P.sinensis juveniles were fed with a commercial dry pellet feed of 46% crude protein and minced fillet of silver carp ans cultured for 122 days.The results showed that the levels of total nitrogen(TN),total phosphorous(TP),Chlorophyll-a(Chl.a) and turbidity in LD treatment were significantly lower than those in HD treatment(P<0.05).The mean TN and TP concentration in LD treatment was 29.3% and 35.7% lower compared to the HD treatment at the end of the experiment,respectively.Mean survival rates,final weight,average growth rates and PER were significantly higher in LD treatment compared with the HD treatment(P<0.05),respectively.Production was significantly affected by stocking density,which was higher in HD treatment,but the net income was higher in LD treatment.The results suggest that turtles with mean weight 55.6 g rearing at a low stocking density(1 ind./m~2) in ponds had a positive effect on overall economic return and was effective at improving turtle growth performance and water quality. 相似文献
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养殖密度对哲罗鱼稚鱼生长和存活的影响 总被引:1,自引:0,他引:1
试验设置了5个养殖密度,分别为1 000、2 000、3 000、4 000、5 000尾/缸,经过70 d的养殖和观察,发现养殖密度对哲罗鱼稚鱼的存活率、肥满度、特定生长率和变异系数的影响并不显著.各密度组的存活率分别为87.7%、94.25%、92.95%、91.45%和91.12%,肥满度为0.728~0.793,特定生长率平均值为3.11%,体质量变异系数为0.49%~18.73%.研究结果表明,哲罗鱼稚鱼完全可以在较高的养殖密度下进行培育. 相似文献