Influence of Hibernation and Dehydration on the Hatching Percentage of Artemia Cyst Collected from Solar Saltpan

The brine shrimp Artemia franciscana is an important live feed for fin and shell fish larval culture. Cysts of Artemia are naturally found in a wide variety of harsh environments where they are exposed to different changing environmental conditions. Artemia cysts are also exposed to different hydration/dehydration (H/D) conditions during the post-harvest processing period in the Artemia processing industry. India has enormous quantity of cyst production every year from solar saltpans. But due to the lack of proper post-harvest processing technology, most of the cyst are sold to very low price to larval rearing industries. The aim of the present study was to find out the effect of different rate of dehydration, and different preservation temperatures for enhancing cyst hatchability. The cysts were collected from Thamarikulam saltpan in Kanyakumari District, Tamilnadu, India. The collected cysts were dehydrated to different percentages and preserved at 0º, -10˚ and -20˚C for different durations. The study disclosed that the cyst required 1.3h for full hydration in 30ppt saline water and reached full dehydration at 16h in saturated saline solution. Among the three preservation conditions, the maximum hatching percentage (77.95%) was observed in the cyst that preserved at -20˚C for 400days.Among the different rate of dehydration and hibernation, the 40% dehydrated cyst allowed to hibernate at -20˚C had the maximum hatching percentage. From this study, it is concluded that the optimum of all dehydration percentage, level of chillness and duration of cold storage had equally influenced in the improvement of cyst quality.