@article{oai:ir.kagoshima-u.ac.jp:00000750,
 author = {HIRATA, Hachiro},
 journal = {鹿児島大学水産学部紀要=Memoirs of Faculty of Fisheries Kagoshima University},
 month = {2016-10-27},
 note = {The experiments were carried out preliminarily in order to know how to introduce an experimental microcosm to the water for mass culture of marine rotifer, Brachionus plicatilis. Round polycarbonate tanks (Pan-Light) with 30 liters were employed in the rearing experiments. About 10 liters of gravels crushed were set on the bottom as a filter. The water was recirculated by an air bubbling through a pipe-like an air lift pump located around the center of the tank. The air volume supplied was increased gradually from 3 to 13 or 15 liters per minute in process of yeast feeding. Marine type of Chlorella was innoculated at the beginning with 6.0 g of KNO_3, 0.6 g of KH_2 PO_4, 0.9 g of Clewat-32 and 0.1 g of Clewat-Ca in the tank. When the Chlorella grew up to the stationary phase, a small number of rotifer were transfered into the water. Frozen marine yeast were fed to the rotifer, after the majority of Chlorella cultured were taken up. The yeast were supplied at 6-hour intervals keeping with a certain amount of feed levels between 100 × and 2,000 × 10^4 cells per ml of yeast. The experiment was repeated three times; Exp. I, II and III, during February and May in a sunny exterior of the Laboratory. Each experiment showed a similar result on the population growth of the rotifer. The maximum density of rotifer cultured in Exp. I, II and III were 1,450, 1,170 and 1,270 individuals per ml, respectively. Higher feeding ratio, 140%, was found in lower temperature, 21.1°C. On the contrary, the lower ratio, 43%, was obtained when it was 27.6°C, the highest temperature through the experiments. It was clear that the feeding ratio, thus, was affected by the water temperature within those ranges. Furthermore, a negative relationships between feeding ratio and population density were also found in each experiment. Typical example on this relationship was obtained in Exp. II . Higher feeding ratio, 400%, was indicated in the cases of lower density, 10 or 25 individuals per ml. However, when the rotifer population grew up to 1,000 per ml, the feeding ratio decreased to 120%. Interesting results, concerning the growth of Chlorella cells in the tank, were observed in the final experiment, Exp. III. The Chlorella cells, which have been taken up once by the rotifer at the middle part of the experiment, grew again in the tank at the end of the rearing. This might be due to the reproduction mechanisms of phytoplankton in the closed-system like an experimental microcosm.},
 pages = {163--172},
 title = {An Attempt to Apply an Experimental Microcosm for the Mass Culture of Marine Rotifer, Brachionus plicatilis},
 volume = {23},
 year = {}
}