K. Yoshimura, K. Usuki, T. Yoshimatsu, K. Tan aka, A. Ishizaki-1997
Suisanzoshoku, 45(2) : 171-177
Abstract:
For the reliable management of rotifer culture, it is most important to estimate the absolute quantities of food organisms provided and rotifer biomass, accurately, simply and rapidly. In this study we tested the usefulness of centrifugation method to measure the biomass of Chlorella regularis and Brachionus rotundiformis as packed volume (PV, ml/l) with a graduated capillary tube (hematocrit tube).
The optimal conditions for centrifugation were first determined as 2808 G (R.C.F.) and 30 minutes. Next, we compared the accuracy of estimation by the conventional direct-counting method under a microscope and by centrifugation using the same rotifer and Chlorella samples. As a result, the centrifugation method (coefficient of variation: 3.9% for Chlorella and 3.6% for rotifers) was found to be more accurate than the conventional counting method (coefficient of variation: 14.1% for Chlorella and 15.3% for rotifers) for estimating rotifer and Chlorella biomass in the medium.
(Genkai, Fukuoka 811-35, Japan)