Effects of Daphnia magna and Artemia nauplii on growth performance in Persian sturgeon Acipenser persicus larvae

This study was carried out in a completely randomized design 3×3×4 factorial arrangement in three periods of rearing in spring 1997. Density of 300 larvae was assigned for each oval tank with 0.1m2 surface area, 30cm deep, a volume of 20lit and 0.25 lit/min of water flow per minute at Shahid Rajaie fish breeding and culture center in Sari, north of Iran. The fries were divided into three groups according to their feeding regimes and fed with each of Artemia or D. magna speratley, and mixture of the two (50% Artemia+50% Daphnia) in ratioes of 80, 100 and 120% of their body weights in the first period and 30,50,70% of their body weights in the second and third period of rearing. Each period lasted 72 hours. The result indicated, significant differences (p