| || || Lal, Monal M.|
| || || Spawning and larval rearing of the monkey river prawn macrobrachium lar (Fabricius, 1798) (crustacea : decapoda : caridea : palaemonidae)|
Author:Lal, Monal M.
Institution: University of the South Pacific.
Call No.: pac In Process
Copyright:Over 80% of this thesis may be copied without the authors written permission
Abstract: The Monkey River Prawn Macrobrachium lar (Fabricius, 1798) is a large palaemonid prawn indigenous to a number of Pacific Island Countries and Territories (PICTs). Because of its size, relatively fast growth rates and a number of other favourable characteristics, it appears to have good potential for aquaculture except for one major constraint; namely the availability of seed stock for grow-out which is severely limited by the inability to rear the larvae from hatch until metamorphosis into post-larvae (PL). A greenwater-type technique developed for M. lar larviculture is described here, and was successful in producing PL, representing possibly the first time that this has been reported for this species. The larvae of M. lar developed through 13 zoeal stages before metamorphosing to PL1, moulting within 22 – 31 or more instars at salinities of 30 ± 1.5 ‰ and temperatures of 28 ± 0.8 l of five post-larvae were produced, after 77, 78, 85, 101 and 110 days of culture respectively. Overall percentage survival to PL1 was very low, at 0.08 %. Larvae were observed to undergo mark-time moulting during development, especially during the later zoeal stages as metamorphosis approached, which lengthened overall culture duration. This is attributed to inappropriate culture conditions, especially in terms of larval nutrition and possibly salinity. A point of difference noted between the feed preferences of M. lar and other Macrobrachium spp. larvae was that the former showed a strong tendency to consume biofloc particles in preference to Artemia nauplii, when both were present in sufficient quantities. The embryonic development of M. lar appears very similar to that which has been described for other species of Macrobrachium. Ovigerous females of M. lar maintained in the laboratory displayed asynchronous and prolonged hatching, which resulted in relatively low larval yields at the commencement of rearing trials.