为探究体重、盐度和温度对不同规格的虎斑乌贼(Sepia pharaonis)幼体耗氧率、排氨率以及其窒息点的影响.采用单因子试验设计和密闭静水法,对不同体重下(0.212、0.385、0.476、0.597、0.754和0.946 g)虎斑乌贼幼体的耗氧率和排氨率,以及不同体重(0.476、0.673、1.341、3.873和4.205 g)幼体的窒息点进行了测定,同时研究了不同盐度(19‰、22‰、25‰、28‰和31‰)和温度(18、21、24、27和30℃)对不同规格[A:体重(0.366±0.042)g,B:体重(0.556±0.038)g,C:体重(0.844±0.051)g]的虎斑乌贼幼体耗氧率(RO)和排氨率(RN)的影响.结果表明:(1)虎斑乌贼幼体体重对耗氧率和排氨率均影响显著(P<0.05).随着幼体体重的增长,耗氧率和排氨率显著下降,个体越小耗氧率和排氨率越大;(2)盐度对幼体的耗氧率和排氨率有显著影响(P<0.05),均随着盐度的增加呈先下降后上升的趋势,其中,A规格和B规格的幼体在盐度25‰时,耗氧率和排氨率显著低于盐度19‰、22‰和31‰时的3个试验组(P<0.05),而与盐度28‰时无显著差异(P>0.05);C规格幼体的耗氧率在盐度28‰时显著低于盐度19‰组(P<0.05),而排氨率在盐度25‰时显著低于盐度19‰和31‰两组(P<0.05).盐度对A规格幼体的氧氮比(O/N)值有显著影响(P<0.05),而对B规格和C规格的幼体无显著影响(P>0.05).(3)温度对不同规格幼体的耗氧率和排氨率有显著影响(P<0.05),均随温度的增长,呈先上升后下降的趋势.其中,A规格和C规格幼体的耗氧率在27℃时,显著高于18和30℃两组(P<0.05),B规格的在水温24℃时显著高于18和30℃(P<0.05);A规格和B规格幼体的排氨率分别在24和27℃时,显著高于其他温度组(P<0.05),C规格的在温度27℃时,显著高于18和30℃两组(P<0.05);温度对A规格幼体的O/N值有显著影响(P<0.05),而对B规格和C规格的幼体无显著影响(P>0.05).(4)虎斑乌贼幼体的窒息点为0.84—1.62 mg/L,随着体重的增加而逐渐降低.%This research was conducted to explore the effects of body weight, salinity and temperature on oxygen con-sumption rates (OR), ammonia excretion rates (NR) and the suffocation threshold of juvenile Sepia pharaonis. The rela-tionship between OR and NR of juvenile S. pharaonis and body weights (0.212, 0.385, 0.476, 0.597, 0.754, 0.946 g), suffocation threshold and body weights (0.476, 0.673, 1.341, 3.873, 4.205 g) were studied. Meanwhile, the effects of various salinities (19, 22, 25, 28, 31), and temperature (18, 21, 24, 27, 30℃) for three sizes of cuttlefish (A: body weight 0.366±0.042 g, B: body weight 0.556±0.038 g, C: body weight 0.844±0.051 g) were revealed by using single-factor design and sealed hydrostatic method. The results were as follows: 1) body weights of juvenile S. pharaonis showed a significant effect on OR and NR (P<0.05), which decreased significantly with the increase of body weights. 2) Salinity had significant effects on the OR and NR (P<0.05), all of which were reduced with the increase of salinity, and then rose. For sizes A and B, the OR and NR of juvenile S. pharanis at salinity 25 were significantly lower than that at salinity 19, 22 and 31 (P<0.05), with the exception of salinity 28 (P>0.05). For size C, the OR of juvenile S. pharanis was significantly lower at salinity 28 than that at salinity 19 (P<0.05). Meanwhile, the NR was significantly lower at sa-linity 25 than at salinity 19 and 31 (P<0.05). The salinity had significant effects on O/N of juvenile S. pharaonis for size A (P<0.05), but not for sizes B and C (P>0.05). 3) The temperature had significant effects on the OR and NR (P<0.05), both of which were elevated with the increase of temperature, and then decreased. For sizes A and C, the OR of juve-nile S. pharanis were significantly higher at 27℃ than at 18℃ and 30℃ (P<0.05). For size B, the OR of juvenile S. pharanis were significantly higher at 24℃ than at 18℃ and 30℃ (P<0.05). For sizes A and B, the of juvenile S. phar-anis were significantly higher at 24℃ and 27℃ than at other temperatures (P<0.05). For size C, the NR of juvenile S. pharanis were significantly higher at 27℃ than at 18℃ and 30℃ (P<0.05). The temperature had significant effects on O/N of juvenile S. pharaonis of size A (P<0.05), but not of sizes B and C (P>0.05). 4) The suffocation threshold of ju-venile S. pharaonis was 0.84—1.62 mg/L, which decreased with increasing body weights.
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