Growth of early phyllosoma stages of the spiny lobster,Panulirus homarus fed with Artemia enriched with different species of microalgae was studied. Freshly-hatched phyllosoma were grown at a density of 10 L-1 in 60 L upwelling tanks supplied with flow-through sea water at 27±0.5° C. Artemia nauplii were enriched with one of three microalgae strains, Chlorella vulgaris (Chlorophyceae), Chaetoceros gracilis (Bacillariophyceae) and Spirulina platensis (Cyanophyceae). The nauplii were provided with microalgae at a concentration of 1.5 ×106 cell ml-1 for 6 hours for enrichment. A fourth group was maintained as a control and was fed unenriched Artemia nauplii. Survival rate of newly-hatched larvae cultured to Stage II with Artemia nauplii enriched with C. vulgaris, C. gracilis,S.platensis and unenriched Artemia were 58.89±1.11, 57.78 ±2.22, 66.11±0.56 and 40.0 ± 1.67% respectively. The survival rate from Stage I to Stage II larvae was significantly (p < 0.05) higher in all the groups fed with enriched Artemia nauplii. The highest survival rate (29.20 ±1.36%) from Stage II to Stage III instar 2/3 was obtained in the group fed with Artemia nauplii enriched with C. vulgaris. Similarly the shortest moult interval from Stage I to III instar 2 (19.5 ±1.44 days) was also observed in this feeding regime. The phyllosoma larvae fed with C. vulgaris enriched nauplii, attained Stage III instar 3 in 22-25 days whereas in the other groups the larvae were in Stage III instar 1/2 at the end of 30 days. The lowest range of total aerobic hetero trophic bacterial load (THB) (0.9 ×103 ±0.14 to 11.0×103±1.15) and
Vibrio spp. load (0.81 ×103 ±0.02 to 5.73 ×103 ±0.2 CFU, ml-1) from day 0 to day 30 in culture water was observed in the group fed with nauplii enriched C. vulgaris. Significant ( p <0.05) size differences were observed in different groups. Thus larval survival, size, moult interval and bacterial load of culture water were significantly influenced by the use of Artemia enriched with microalgae.

Panulirus homarus, phyllosoma, Artemia, microalgae, larval rearing