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在室内不用药、不换水条件下,采用150、350、550和850 ind.m-34种布苗密度,通过60 d淡水养殖试验,探讨了密度对凡纳滨对虾成活率、生长特征与水质的影响以及养殖的合适密度。结果表明,随密度增加水质逐步下降,如DO由6.65 mg.L-1降至6.18 mg.L-1,pH由8.31降至8.15,TNA由0.313 mg.L-1升至0.538 mg.L-1,CODMn由14.36 mg.L-1升至23.29 mg.L-1,各组上述指标除NO2--N间无差异外(P>0.05),其余相应指标间均存极显著(P<0.01)或显著差异(P<0.05);成活率随密度增加而下降,由90.5%降至24.2%,但第3、4(35.4%、24.2%)无显著差异(P>0.05),其余组间差异极显著(P<0.01),但各组水质指标基本均在幼虾生长合适范围;第1~第3组增长量(6.07~6.23 cm)、增重量(4.042~4.575 g)与增长率(430.3%~551.1%)无显著差异(P>0.05),与第4组存在极显著(P<0.01)或显著差异(P<0.05);养殖产量第3组最高(799.6 g.m-3,为最低的第4组的1.8倍;试验虾体长与养殖天数间具线性相关(L=at+b)(a,0.075 1~1.044 0;b,0.897 9~1.189 3),体重与体长间呈幂函数关系(W=aL3)(a,0.011 6~0.013 9);据养殖综合效果,室内封闭式淡水养殖凡纳滨对虾可据自身条件,布苗密度可参考350~550 ind.m-3确定。
The density of 150, 350, 550 and 850 ind.m-34 seedlings was used indoors without changing the water condition, and then the freshwater aquaculture test for 60 days was conducted to investigate the effects of density on the survival rate, growth characteristics and The impact of water quality and the appropriate density of culture. The results showed that with the increase of density, the water quality decreased gradually, such as the DO decreased from 6.65 mg.L-1 to 6.18 mg.L-1, the pH decreased from 8.31 to 8.15, and the TNA increased from 0.313 mg.L-1 to 0.538 mg.L- 1, the CODMn increased from 14.36 mg.L-1 to 23.29 mg.L-1, the above indexes in all groups except NO2 - N showed no significant difference (P> 0.05) ) Or significant difference (P <0.05). The survival rate decreased from 90.5% to 24.2% with the increase of density, but no significant difference was found between the third and fourth groups (35.4%, 24.2%, P> 0.05) (P <0.01), but the indexes of water quality in each group were all within the appropriate range of growth of juvenile shrimp. In the first to the third group, the growth rate (6.07 ~ 6.23 cm), the weight gain (4.042 ~ 4.575 g) and the growth rate 430.3% -551.1%) (P> 0.05). There was a significant difference between the third group and the fourth group (P <0.01) or the significant difference (P < (L = at + b) (a, 0.075 1 ~ 1.044 0; b, 0.897 9 ~ 1.189 3), body weight and body length According to the comprehensive effect of culture, indoor closed freshwater culture of Litopenaeus vannamei can according to its own conditions, the density of cloth seedlings can refer to 350 ~ 5 (a, 0.011 6 ~ 0.013 9) 50 ind.m-3.