| Popis: |
Aquaculture is currently the fastest growing sector of protein production, and is expected to overtake the harvest of wild fisheries. Limitations in nutrition, specifically fatty acid nutrition, are preventing even more dramatic growth of many species of commercial importance. Currently, much of the research involving fatty acids examines requirements as being correlated to thermal guilds (warm vs. cool water) or salinity tolerance (marine vs. freshwater). However, recent studies have revealed the potential for trophic level to be as much, if not more, influential in determining fatty acid requirements of a species. As such, two feeding trials were conducted to determine the requirements of two species of different trophic levels (Oreochromis niloticus and Trachinotus carolinus) based on C18 PUFA vs. LC-PUFA. Nile Tilapia, O. niloticus, exhibited similar growth regardless of the inclusion of C18 PUFA or LC-PUFA, however, tissue fatty acid profiles were influenced per the diet provided. As such, it was concluded that Nile Tilapia exhibit the capacity to effectively synthesize LC-PUFA from C18 PUFA as is seen in many species that occupy low trophic levels. Florida Pompano, T. carolinus, did not exhibit any significant differences in growth regardless of the diet provided, but numerical differences indicated benefits towards inclusion of dietary LC-PUFAs. Similar to O. niloticus, tissue fatty acid profiles were significantly affected by dietary treatment. Based on numerical differences in growth performance and significant differences in tissue fatty acids, it was concluded that Florida Pompano show a typical carnivorous requirement for LC-PUFA. |
