FOOD UTILIZATION IN ARTEMIA FOR GROWTH, REPRODUCTION, AND MAINTENANCE

Using marine Chlamydomonas as food, the food requirement of bisexual b rine shrimp Artemia franciscana was estimated in terms of nitrogen in order to assist production. The ingested food was theoretically fracti onated to the maintenance, somatic growth and reproduction of nauplius and cyst. While feeding marine chlamydomonad (5 pg N/cell) to the shr imp (L mm), the daily maintenance ration was almost proportional to th e cube of body length (2.952) and was 2844 cells/shrimp/day for shrimp of 1 mm length at 28-degrees-C. On the basis of ingested food, the so matic food conversion efficiency was 67%. The efficiency of nauplius p roduction was 23% and that of cyst production was 44%, based on the fo od taken by a pair of shrimps. Including the reproductive products as growth, the gross conversion efficiency was 16% in the groups from whi ch the maintenance ration and somatic conversion factor were obtained, and 24% in the groups from which the reproductive conversion factors were obtained. The reproductive growth per total growth increased with the body length and the feeding rate, and was zero below 5.7 mm in le ngth and 1.0 times the daily maintenance ration.