Maria Charles, P.
Abstract:
Egg production, energetics and larval survival of three successive spawns of the prawn Macrobrachium lamarrai (H. Milne Edwards) are presented. Females measuring 48+/- 8 mm total length lay an average of 85 +/- 35.80 +/- 29 and 72+/-26 eggs in three consecutive spawns.
The mean size of the freshly laid egg is 1.45 +/- 0.25 mm in length and 1.11 +/_ 0.18 mm width. However, the size of the egg varied between the observed clutches. The mean difference of the egg size was 0.23 mm length and 0.15 mm width, and 0.44 mm length and 0.23 mm width between the spawns I & II and I & III respectively.
The freshly hatched larva of the first spawn containing 1.336+/-0.05 calories of energy survives for 11 days on reserve yolk; where as the larvae of the second and third spawns have a mean difference of 0.2431 and 0.3645 calories less then that of the first spawn and hence could survive only for a period of 9 and 8 days respectively. This significant difference in the larval survivability among the three successive spawns suggests the aquacultural importance of the seedlings of the first spawn.
This study was funded as a Research Associateship award to PMC by the School of Energy, Madurai Kamaraj University, India.
(Department of Zoology, Government Arts College, Mandanam, Madras-600 035, India)
(to be continued)
---------------------------------------------------------------------------------