Studies on the reduction of environmentall road in the waste water from rotifer culture by the introduction of Chemostat System

目前，从法律的角度来看，孵化场的废水已经失控。然而，从“生态系统共存”的角度来看，“零排放”应该在不久的将来实施。本节目通过对“食物向轮虫的氮素转化效率”、“物料流”、“轮虫品质”等方面的精密实验，探讨了最新发明的“chemostat -轮虫-生产系统”与典型的普通生产系统batch -culture system的优势。在批培养体系中，游离氨的增加影响和降低了L型轮虫和S型轮虫的食物转化效率，导致水中未同化食物的爆发。因此，与收获的轮虫数量相比，有机物质的浓度较高。在恒化系统中，测定生产效率（轮虫氮除以同化食物氮）。l型轮虫的最大值为40%，高于s型轮虫的30%。总体而言，Chemostat体系的氨排放量低于batch -culture体系，不到batch -culture体系的四分之一。以碳、氮含量作为评价采伐轮虫活力的指标。间歇式培养体系的细菌数量远低于恒化培养体系，这可能是由于随着时间的推移，间歇式培养的环境条件逐渐恶化所致。

Waste waters from hatcheries are out of control in the eye of the law at present. "Zero-emission" should be imposed, however, from the view point of "Exist together Ecosystems" in the near future. In this program, we discussed advantages of "Chemostat-rotifer-production-system, the newest invention" after precision experiments on "nitrogen (N) conversion efficiency from food provision to rotifer", "material flow" and "rotifer quality" in comparison with Batch-culture-system, the typical ordinary production system.In Batch-culture-system, increasing unionized-ammonia affected and lowered the food conversion efficiency in both L and S type rotifers, which induced an outbreak of unassimilated food in water. As a result, the concentration of organic substances was high compared by the amount of harvested rotifers.In Chemostat system, production efficiency (rotifer N divided by assimilated food N) was examined. The maximum value in L-type rotifer was 40% that was higher than the 30% in S-type rotifer. Collectively, ammonia emission from Chemostat system was lower than that from Batch-culture-system, and it was less than quarter of Batch-culture-system.As an index of the activity of harvested rotifers, carbon and nitrogen contents were evaluated. Those from Batch-culture-system were far less than the ones from Chemostat system, which may because of the worsening environmental conditions in Batch-culture as time elapsed.