해산 자치어의 먹이생물로써 섬모충 Euplotes sp.의 평가

Abstract

This study was carried out to evaluate the ciliates Euplotes sp. as a live food for marine fish larvae. The ciliates and the rotifers Brachionus plicatilis, which were cultured with the baker's yeast Saccharomyces cerevisiae and the <TEX>$\omega$</TEX>-yeast emulsified with cuttle fish liver oil, were supplied to the larvae of flounder Paralichthys olivaceus and grouper Epinephelus akaara. Considering the size difference between the ciliates 68 <TEX>$\cdot$</TEX> 7 <TEX>$\mu$</TEX>n and the rotifers 160 <TEX>$\cdot$</TEX> 20 <TEX>$\mu$</TEX>n, the rotifers and ciliates were supplied to the larvae tank with the density of 2 inds./mL and 20 inds./mL, respectively. The survival rate and growth in length of the flounder larvae fed on rotifer were significantly higher than those on Euplotes sp.. In grouper larvae which have a small mouth diameter, even the survival rate of the larvae fed on the ciliates was better than that on the rotifers, it was very low less than <TEX>$20\%$</TEX>. Therefore, Euplotes sp. seem to be incongruent as a live food for marine fish larvae.