Live feeds cultures

Therefore, a better technique seems to be to try to replace the existing, potentially pathogenic microllora by one that is harmless or even beneficial to the fish or shrimp larvae, by applying probiotic mixtures to the live feed cultures, eventually preceded by an initial disinfection treatment. Several studies (e.g. Skjermo and Vadstein, 1999 Gatesoupe, 2002) proved that this is feasible sometimes with enhanced performance of the predator larvae. 

This chapter reviews currently used techniques to culture, harvest, treat and preserve these three groups of live feed. New trends are identified and possibilities for future research and development are set out. 

Ground-breaking new developments on formulated feed are not common. Progress tends to be stepwise whUe, in addition, the degree of successful replacement of live feed varies with the species. It is well known that for most commercially farmed freshwater fish, with their relatively larger larvae, complete substitution is possible there, the whole culture can... 

CUTTS c J (2002) Culture of harpacticoid copepods potential as live feed for rearing marine fish. Advances in Marine Biology 44 295-316. 

MCKINNON A D, DUGGAN S, NICHOLS P D, RIMMER M A, SEMMENS G and ROBINO B (2003) The potential of tropical paracalanid copepods as live feeds in aquaculture. culture 223 89-106. 

A few studies have analysed the bacterial community associated with live feeds. Molecular studies have shown that bacterial communities associated with Artemia can be highly variable with time (McIntosh et al, 2008 Bjornsdottir et al, 2009) and it is possible that this is the situation in most commercial hatcheries. Nevertheless, V. alginolyticus has consistently been reported as the dominant member of the culturable bacterial community of Artemia (Villamil et al, 2003 Thomson et al, 2005 H0j et al, 2009). A... 

MCINTOSH D, II B, FORWARD B S, PUVANENDRAN V, BOYCE D and RITCHIE R (2008) CultUre-independent characterization of the bacterial populations associated with cod Gadus morhua L.) and live feed at an experimental hatchery facility using denaturing gradient gel electrophoresis. Aquaculture, 275,42-50. 

With the development of the aquaculture industry and the need by hatcheries to rear larval and juvenile aquaculture animals came the need for production of microalgae as live feeds. While some hatcheries grow microalgae in multiples of relatively small scale culture containers, for example 20 litre carboys, it is more common for miCToalgal cultures to be grown in disposable plastic bags (200-1000 litres is typical) that are either supported vertically (Plate 9.1b) in metal frames or lie horizontally. 

Provision of live foods is currendy necessary for the early stages of many aquaculture species because acceptable prepared feeds have yet to be developed. Algae is routinely cultured for the early stages of molluscs produced in hatcheries. Once the molluscs are placed in growout areas, natural productivity is depended upon to provide the algae upon which the shellfish feed. 

There are also some active steps that you can take to avoid cultural problems. To reduce the chances of hitting a tree with a mower or trimmer, plant a groundcover or apply mulch around the base of the tree so you won t have to trim close to the trunk. During the winter, though, pull the mulch away from the base of the tree otherwise, the mulch will provide a great place for mice to live and feed on the bark and roots. 

Figure 4.6. The two MBR types for bioartificial organs, a separate plasma and cells configuration. 1 plasma or culture medium feed, 2 oxygen feed, 3 oxygen exit, 4 plasma or culture medium exit, 5 living cells and medium, b perfusion MBR, 6 hollow fibers for oxygen feed, 7 external shell, 8 spirally wound polyester film, 9 anchored cells in a 3D matrix. Adapted from Legallais et al. [4.41].

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