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71.
以体重0.672~4.827g的日本沼虾(Macrobrachium nipponense)和3.678~43.163g的克氏原螯虾(Procambarus clarkii)为试验对象,研究这两种虾的胃容量及其与体长、体重间的关系。结果表明,日本沼虾和克氏原螯虾胃容量随着体重和体长的增加而增加;将日本沼虾、雄性克氏原螯虾和雌性克氏原螯虾的胃容量(y)和体重(x)进行回归分析,分别得方程式:y=0.021 5x+0.006 5(r2=0.948 5),y=0.044 7x-0.008 5(r2=0.964 8),y=0.043 6x+0.0519(r2=0.978 7);3.009~4.827 g的日本沼虾比胃容量显著小于0.672~2.811g的个体,12.967~42.071g的雄性克氏原螯虾比胃容量显著小于3.678~9.754 g的个体,不同规格的雌性克氏原螯虾比胃容量差异不显著。 相似文献
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克氏原螯虾苗种规模化繁育技术 总被引:1,自引:0,他引:1
为解决克氏原螯虾苗种规模化供应短缺问题,以洪泽湖地区克氏原螯虾为研究对象,在研究、掌握本地区克氏原螯虾繁殖习性的基础上,设计并建设了由700 m2大棚产卵池和50 m2加温孵化温室及若干特制网箱组成的苗种规模化繁育设施.2007年9月分批次将16 443只成熟的克氏原螯虾亲虾放入大棚产卵池特制网箱,通过降低光照、微孔增氧、循环流水等措施,先后获得抱卵虾6 053只,平均抱卵率为45.7%;抱卵虾移入温室后,在控温、流水条件下孵化,获得了平均体长0.88 cm的稚虾76.9万尾,平均孵化率为81.1%. 相似文献
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对克氏原螯虾(Procambrusclarkii)的耗氧率、二氧化碳排出率及氨氮排泄率进行了测定,并研究了能源物质的供能比。结果表明,体重(22.25±14.35)g的克氏原螯虾在水温(20.0±0.5)℃时,耗氧率为(0.191±0.081)mg·g-1·h-1,CO2排出率为(0.207±0 085)mg·g-1·h-1,NH3-N排泄率为(0.669±0.199)μg·g-1·h-1,能耗率为(2.94±1 19)J·g-1·h-1;试验虾代谢中蛋白质、碳水化合物和脂肪提供的能量比为2.7∶29.9∶67 4;耗氧率(R0)与体重(m)负相关,关系式为R0/(mg·g-1·h-1)=1.3565(m/g)-0.6882。 相似文献
78.
溴氰菊酯对克氏原螯虾肌肉组织的毒性研究 总被引:1,自引:0,他引:1
为研究溴氰菊酯对克氏原螯虾的毒性效应及致毒机制,实验将克氏原螯虾成虾暴露于农药溴氰菊酯0.5、0.1和0.005μg/L三个浓度的药液中24h后,采用透射电镜观察克氏原螯虾肌肉组织超微结构损伤情况,并以细胞色素氧化酶活力(CCO)、乳酸脱氢酶活力(LDH)和乳酸(LD)含量为生物标志物评价溴氰菊酯对克氏原螯虾肌细胞呼吸产能功能的影响。结果显示,三个浓度的溴氰菊酯都会造成肌细胞超微机构不同程度的损伤,且浓度越大损伤越严重,损伤主要表现为肌原纤维断裂、肌浆网溶解,线粒体溶解。此外,三个浓度的溴氰菊酯都会对CCO活力、LDH活力和LD含量产生影响。其中0.1 μg/L的溴氰菊酯在6~24 h的暴露处理过程中会对肌肉的CCO活力产生极显著的抑制作用(P<0.01), LDH活力增强,乳酸含量上升。研究表明,0.5、0.1和0.005μg/L溴氰菊酯可以造成克氏原螯虾肌细胞超微结构损伤,激活细胞的厌氧呼吸,在组织中产生大量的乳酸,乳酸的蓄积会对造成细胞酸化而加重对细胞的毒性。 相似文献
79.
Shiyu Jin Lisa Jacquin Yan Ren Jixin Yu Wei Li Sovan Lek Jiashou Liu Zhongjie Li Tanglin Zhang 《Aquaculture Research》2019,50(3):934-943
Overfeeding in aquaculture can lead to suboptimal growth and increased production costs. Red swamp crayfish, Procambarus clarkii, is one of the most noteworthy species cultured in China, but little information is available on the optimal feeding levels of this species, especially in ponds cultured with macrophytes. In this study, we tested the effects of five different feeding levels (20%, 40%, 60%, 80% and 100% satiation) of an artificial diet on growth performance and muscle composition of juvenile P. clarkii in 15 concrete ponds cultured with the macrophyte Hydrilla verticillata (three replicates for each treatment). The results showed that growth performance decreased only when feeding levels were below 60% satiation. Muscle composition analysis revealed that the moisture and ash contents of muscle did not vary significantly with feeding levels but that the lipid and protein contents of muscle significantly decreased when P. clarkii was fed to 40% satiation. Stable isotope analysis suggested a shift in crayfish diets to easily available H. verticillata when feeding levels decreased. With this study, we hope to encourage crayfish farmers to reduce feeding levels and increase natural food items such as macrophytes in cultured ponds to maximize crayfish yields and reduce production costs. 相似文献
80.
Jinghao Li Jiayao Li Wei Li Ying Sun Xiaofei Liu Mingming Liu Yongxu Cheng 《Aquaculture Research》2019,50(7):1834-1843
A 60‐day study comparing the growth performance; proximate composition and the digestive, immune and antioxidant enzyme activities of juvenile red swamp crayfish (Procambarus clarkii) reared using biofloc technology (the biofloc group) or a commercial diet (the control group) in zero‐water exchange indoor tanks was performed. A commercial diet was fed to both groups, and the daily feeding amount in the biofloc group was 40% less than that in the control group. Wheat bran and glucose were used in the biofloc group to ensure a C/N ratio >15 and the same feeding energy as that given to the control group. After 60 days of feeding, the final weight, weight gain and specific growth rate in the biofloc group were significantly higher than those in the control group. Furthermore, proximate composition analysis showed that the total hepatopancreatic lipid and ash contents of the biofloc group were significantly higher than those of the control group, and the intestinal and hepatopancreatic pepsin activities in crayfish in the biofloc group were higher than those in crayfish in the control group. Moreover, higher hepatopancreatic lipase and cellulase activities were observed for the biofloc group than for the control group. Biofloc technology promoted the health of the crayfish in terms of their immune and antioxidant enzyme activities. Based on the results of this study, biofloc technology is more effective than traditional commercial diets for the farming of juvenile crayfish. 相似文献