Abstract:
The present work evaluates the effectiveness of nine brands of artificial larval diets manufactured by different process technologies, in the form of microparticulate, spray dried formulations, and microencapsulated feeds. These diets have been investigated to evaluate their physical characteristics in laboratory feed trial with Penaeus monodon (Fabricius) larvae. Larval growth and survival rates were recorded to assess diet performance. Highest growth and survival of shrimp larvae were obtained using microencapsulated feed in conjunction with 10 cells /1-1 of microalgae. Results indicate that the composition of a few of most artificial larval diets alters dramatically within a few hours of immersion in seawater, causing significant changes both to food particle size and to the culture water environment. Unstable feeds leach dietary compounds into culture water enhancing microbial growth, producing ammonia and nitrite which rapidly reach toxic levels. There is a general decline in both larval survival and growth with increasing levels of these toxicants, although it is unlikely that they can be responsible for the poor performance on some diets. Analysis shows that feed stability in culture water over the first 24 h after feeding is the most critical factor. It is concluded that if artificial larval diets are used as total replacement of all live feeds in penaeid shrimp hatcheries, feed technology must concentrate on the production of stable low leach diets, of acceptable particle sizes.
Page(s):
135-142
DOI:
DOI not available
Published:
Journal: Pakistan Journal of Zoology, Volume: 24, Issue: 2, Year: 1992