Abstract:
Juvinile abalone, Haliotis asinina Linne. were reared in series of 37 x 25 x 38 cm3 floating cages in 2.80 x 1.20 x 0.69 m3 ponds with flow-through sea water system. All 2 trials were conducted at EMDEC. Abalones used for the experiment were about 1-2 months old. The first trial (October-December 1992) was designed to compare types of feed, pelleted and coated on plastic PVC using Nosan no.3 as control diet (formulae 5). The second trial (March April 1993) was designed to examine 4 pelleted formulae. All experimental treatment had 3 replications. In the first trial, after 8 weeks coated feeds on plastic PVC gave better weight gain compared to pelleted feeds. The average weights, average shell lengths, the feed conversion efficiency and the survival rate of juvenile abalones fed diet 1, 2, 3, 4, 5 were 6.41, 14.48, 12.75, 9.94, 41.61 mg/day, 40.28, 46.23, 57.60, 49.08, 117.45 um/day, 0.20, 0.36, 0.59, 0.37, 0.93, and 100, 100, 98.33, 100%, respectively. In the second trial, the average weights and average shell lengths of juvenile abalone fed diet formulae 6, 7, 8, 5, were 8.30, 1.96, 2.38, 23.57 mg/day and 44.28, 20.89, 17.32, 98.75 um/day, respectively. Survival rates of formulae 6, 7, 8 and 5 were 100%, 95 %, 98.33 %, 98.33 %, while feed conversion efficiency were 0.23, 0.03, 0.08, 0.61, respectively. Water quality during the trials was in normal levels. It was concluded that both coated and pelleted diet were suitable for juvenile abalone but coated diet seemed to provide a better growth than the pelleted diets.