| 查看: 555 | 回复: 1 | ||
JOE_橙痕银虫 (小有名气)
|
[求助]
英文摘要求大神修改，给出指点意见
|
|
本实验采用氨态氮与亚硝态氮耦合、亚硝态氮与盐度耦合和氨氮与pH耦合三组环境胁迫对凡纳滨对虾的生长及摄食进行亚慢性毒理实验。氨态氮梯度设置为0、5、10 mg/L三个水平，亚硝态氮水平梯度为0、5、10 mg/L，pH梯度设置为7.6、8.2、8.8，盐度的梯度设置为5、15、25三个水平。通过每天都给予恒定剂量的氮，连续培养7天后，对虾的特定生长速率、摄食率和饲料转化率均随着氨氮或亚硝态氮的增高而降低（P<0.05）。最高浓度的氨态氮（10mg/L）与亚硝态氮（10mg/L）组与对照组相比较，特定生长率、摄食率和饲料转化率分别下降了18.31%，14.68%和17.49%。当氨态氮作为氮添加的情况下，pH7.6和pH8.8的参数均要低于pH8.2（P<0.05）。但高pH能进一步加剧氨态氮的毒性，pH8.8的存活率显著低于pH7.6和8.2（P<0.05），且pH8.8和氨态氮10 mg/L的对虾在实验第二天全部死亡。当亚硝态氮作为氮添加时，盐度对摄食率并无显著影响（P>0.05），但对特定生长率和饲料转化率影响显著（P<0.05）。在亚硝态氮10 mg/L时，盐度15和25的特定生长率、饲料转化率和存活率均高于盐度5。结果表明高盐度能够缓解亚硝态氮对于对虾生长的抑制，而高pH则会加剧氨态氮对于对虾的毒性。 In this study, sub-chronic toxicological experiments were carried out on the growth and feeding of Litopenaeus vannamei by coupling ammonia-nitrogen with nitrite-nitrogen, coupling with nitrite-N and salinity, and coupling with ammonia-N and pH. The gradient of ammonia-N is set to 0, 5, 10 mg/L, the gradient of nitrite is 0, 5, 10 mg/L, the pH gradient is set to 7.6, 8.2 and 8.8, and the gradient of salinity is 5, 15, 25. After 7 days of culture, the growth and feed intake parameters decreased as the increasing concentration of nitrite-N or ammonia-N under nitrite-N and ammonia-N treatments (P<0.05). Comparing with control treatment, the specific growth rate, feed intake and feed conversion rate decreased 18.31%, 14.68% and 17.49% in highest concentration of ammonia-N and nitrite-N, respectively. In the culture with ammonia-N as exclusive N source addition, the parameters of pH7.6 and pH8.8 were significantly lower than that of pH7.6 (P<0.05). Furthermore, the survival rate of pH8.8 was lower than both of pH 7.6 and pH8.2 (P<0.05), and all individuals died on the second day in the pH 8.8 and 10 mg/L ammonia-N treatment, suggesting that high pH value will enhance the negative effects induced by ammonia-N to L. vannamei. In the culture with nitrite-N as exclusive N source addition, the salinity had no influence on feed intake (P>0.05), but had significant effects on the specific growth rate and feed conversion (P<0.05). when the concentration of nitrite-N reached 10 mg/L, the specific growth rate, feed conversion and survival rate of both salinity 15 and salinity 25 were higher than that of salinity 5 (P<0.05). The result showed that high salinity could alleviate the inhibition of nitrite-N on growth, while high pH value would exacerbate the toxicity of ammonia-N to L. vannamei. |
回复此楼» 猜你喜欢
材料调剂
已经有9人回复
-
321求调剂
已经有12人回复
-
调剂求助
已经有4人回复
-
22408 266求调剂
已经有3人回复
-
266分，一志愿电气工程，本科材料，求材料专业调剂
已经有4人回复
-
279求调剂
已经有5人回复
-
一志愿华南师范大学-22408计算机-292分-求华南师范大学调剂
已经有3人回复
-
材料与化工306分找调剂
已经有10人回复
-
环境工程297分求调剂一志愿杭高院
已经有16人回复
-
296材料专硕求调剂
已经有12人回复
2楼2017-05-06 12:03:42
10