口虾蛄幼体开口饵料及早期生长的初步研究

A Preliminary Study on First Feeding and Early Growth of Larval Oratosquilla oratoria

【目的】研究不同开口饵料对口虾蛄(Oratosquilla oratoria)幼体存活和生长的影响。【方法】选用轮虫、轮虫+卤虫无节幼体、卤虫无节幼体、枝角类、小球藻等为开口饵料培养口虾蛄幼体20d。用卤虫无节幼体作为单一饵料进行口虾蛄幼体的早期生长研究。【结果】幼体开口后6 d(Z4期),单独投喂小球藻、轮虫、枝角类的口虾蛄幼体成活率为0%,而投喂轮虫+卤虫无节幼体、卤虫无节幼体的口虾蛄幼体成活率则相对较高,分别为89%和87%,两组间差异无统计学意义(P>0.05);在实验7～19 d内(Z5-Z8期),轮虫+卤虫无节幼体组成活率最佳,达71%,卤虫无节幼体组幼体成活率则为50%。单一投喂卤虫无节幼体0～15 d(Z2―Z7期)内口虾蛄幼体持续生长,15 d(Z7期)后口虾蛄不再生长,其体长与头胸甲长、腹部长、尾扇长等存在显著的线性回归关系(P<0.01)。【结论】基于实验结果和口虾蛄幼体的摄食特性,建议口虾蛄幼体的开口投喂方案为幼体开口后的0～15d内(Z2―Z7期)主要投喂轮虫+卤虫无节幼体饵料,15 d后(Z7期)逐渐转至其他生物饵料。

【Objective】To study the effects of first feeds on survival and growth of larval Oratosquilla oratoria.【Method】Oratosquilla oratoria larvae were fed with rotifera, rotifera ＋ artemia nauplius, artemia nauplius, cladocerans, chlorella for 20 days, and the larvae were fed with artemia nauplius only to study the early growth.【Result】On the 6th day （Z4 phase） after larva opened the mouth, the survival rate of larval O. oratoria fed with chlorella, rotifera and cladocerans were 0%, but the survival rate of larvae O. oratoria feeding rotifera ＋ artemia nauplius, artemia nauplius larvae was higher, at 89% and 87% respectively, without significant difference between the two groups （P 〉 0.05）; During the 7 – 19 days （Z5 – Z8 phase） of the experiment, the survival rate of the group feeding rotifera ＋ artemia nauplius was the highest, up to 71%, the survival rate of the group feeding artemia nauplius was 50%. Using artemia nauplius as a single bait for the early growth study of juvenile O. oratoria, the results showed that the growth and development of juvenile O. oratoria were normal at the first 0 – 15 days （Z2 – Z7 phase）, and the biological indicators began to decline after the 15th day （Z7 phase）. There was a linear correlation relationship between the body length and the length of the head cuirass, abdomen and the tail fan. The test showed that the relationship between them was significant （P 〈 0.01）. 【Conclusion】The feeding characteristics based on the test results suggested that the optimal feeding strategy was to feed the juvenile O. oratoria with rotifera ＋ artemia nauplius within 0 – 15 days （Z2 – Z7 phase） after larvae opened the mouth and gradually transferred to other biological bait.