IN-VITRO EMBRYO CULTURE AND EFFECT OF SALINITY ON THE EMBRYONIC-DEVELOPMENT OF THE CULTIVABLE FRESH-WATER PRAWN MACROBRACHIUM-MALCOLMSONII (EDWARDS,H.MILNE)

Five culture media prepared by using varying quantities of NaCl, KCl, CaCl2, MgCl2, MgSO4 and NaHCO3, were used to test their feasibility fo r the embryo culture of Macrobrachium malcolmsonii. A reduction in inc ubation period (11 days) was obtained in the medium V, compared with o ther media (I to IV). The hatching percentage was higher in the medium V (69.7%) than in other media. Hence, medium V is suitable for in vit ro embryo culture of Macrobrachium malcolmsonii. In in vitro culture, eggs hatched on the 12th day had a survival of 66.7% in 0.5 ppt salini ty, whereas in 2, 4, 6, 8 and 10 ppt salinities mortality occurred in III, II and I stages of embryonic development, It was also noted that more than 35 eggs in a cluster lead to mortality.