Which live feed to use to grow the larvae? Not all live feed have the same nutritional value or functional value as others. This is particularly applicable to the phytoplankton used during the larval phases of fish and shrimp. In the case of zooplankton, the two most commonly used are rotifers and brine shrimp although others have been used and are used in particular situations. Nowadays, it is also possible to find algae concentrates in place of freshly produced algae.
Feeding of use of dry feed with respect to live feed use. Live feed carries a cost related to the culture and production of good quality organisms for feeding the larvae. In addition to the practical cost of this production, the process is more liable to variations in quality and in some cases market availability as well as being a potential source of bacterial loading. Dry feeds on the other hand should be of more consistent quality and are much easier to handle and manage and this has resulted into considerable effort being applied to reduce the use of live feed, particularly Artemia replacement, wherever possible and as much as possible.
Frequency and method of delivery of live feeds. Live feed feeding management can greatly influence the development of larvae. There are also practical implications to how often and how the live feeds are delivered to the larval tanks which can have a big impact on the economic success of the rearing.
Optimal larval development is often not achieved by the use of live feed alone. It is for this reason that both rotifers and Artemia are generally enriched with specialised products to enhance their nutritional composition prior to feeding to larvae in the rearing tanks. These enrichments can come in various forms and the strategy by which they are applied can vary from one product to the other.
Culture techniques applied to grow the live feed. There are many approaches to culturing live feed and these different techniques may or not have an impact on the nutritional quality of these organisms with regard to fish and shrimp larval development.
LF as Carriers
Live feed can also be used as carriers of beneficial materials, such as prebiotics, probiotics, digestion enhancers, growth enhancers, health enhancers and stress reducing compounds. How much of such materials are added to the live feed culture system and subsequently fed to the larvae will depend on the product being used.
Dry Feed Management
Feeding management of dry feed related to feed sizes, feeding frequency and quantities. The physical characteristics of a dry feed means that products can have various sizes, sinking, leaching and disintegration characteristics. All these parameters have to be considered when setting up a feeding regime for larvae in relation to larvae size and water quality of the tank.
Dry Feed Ingredients
Ingredients used in the dry feed. The choice of ingredients used in a dry formulated feed has a tremendous impact on the survival, quality and growth of fish and shrimp larvae. The quality of the ingredients both in terms of freshness but also nutritional composition are essential to the success of the final product.
Dry Feed Production
Production technology to make dry feed. Today there are many technologies available for the production of dry feeds for larvae. Processing can have a tremendous effect on the nutritional quality of the end product. However, nutritional quality is not the only aspect affected by processing, since the actual physical characteristics can be just as important and in some cases more important in determining the success of the dry feed.
Dry Feed & Water Quality
Effect of dry feed on water quality and general culture conditions. Good water quality is essential for the successful rearing of fish and shrimp larvae. Water quality is affected not only by the rate of exchange of water going into the tank, but also the nutritional inputs, particularly the dry feed. A proper cleaning management is essential especially when larger quantities of dry feed are being used.