蚂蟥与螺蛳耗氧率、窒息点相关性及最适投喂方式的研究

采用静水呼吸室法测定不同质量蚂蟥和螺蛳的耗氧量、耗氧率和窒息点,生物量测定法研究不同投喂方式对蚂蟥生长的影响。结果表明:25℃条件下,蚂蟥和螺蛳耗氧量与质量呈正相关(P0.05),窒息点随质量增大而增大(P0.05)。蚂蟥耗氧率与质量呈负相关,螺蛳耗氧率随质量增大呈先增大后减小趋势。投喂方式对蚂蟥终末质量、SGR,WGR和死亡率影响不显著,对进食比例影响显著(P0.05)。蚂蟥最适投喂频率为3 d投喂1次,应根据蚂蟥和螺蛳各阶段耗氧量及窒息点,结合养殖密度、水体面积以及换水频率,科学合理计算出螺蛳的投喂量。

Study on correlation of oxygen consumption rate and suffocation point of Whitmania pigra and Bellamya purificata and optimum way of feeding Whitmania pigra

The oxygen consumption, oxygen consumption rate and suffocation point of different quality Whitmania pigra and Bellamya purificata were determined by hydrostatic breathing room method. The effects of feeding modes on growth of W.pigra were determined by biomass. The results showed that the oxygen consumption correlated positively with the weight of W.pigra and B. purificata(P < 0.05), suffocation point increased with the increases of the weight(P < 0.05).Oxygen consumption correlated negatively with the weight of W. pigra, the oxygen consumption rate of B.purificata first increased and then decreased with the increasing of the weight. Feeding modes had no significant effects on the finial weight, SGR, WGR, death rates of W. pigra. Feeding modes had significant effects on eating ratio. It suggested that the optimum feeding frequency of W. pigra was once every three days. Scientific and reasonable feeding amount of B. purificata should be calculated based on oxygen consumption and suffocation point of W.pigra and B.purificata at every period. Meanwhile, stocking density, water area and water exchanging frequency should be taken into consideration.