A low-cost method of rearing multiple batches of fish

Experimental studies based on inferential statistics typically require the rearing of many batches of eggs or fish separately, If this is done with co nventional fish rearing methods, the need for laboratory space and equipmen t are normally very high. This may prevent many researchers from experiment ally approaching problems in fish genetics or ecology, especially if treatm ent differences are expected to be small. We have developed and successfull y tested a new procedure with Coregonus sp. fry. Eggs were hatched in Petri dishes kept at 6 degreesC. Yolk-sac fry were reared in a hanging bag syste m at 15 degreesC with continuous water exchange. We estimate that our new f ry-rearing method reduces space needs, infrastructure and material costs by a factor of 10 or more, while beings comparable to previously described me thods with respect to animal welfare requirements and the experimenter's wo rking time. (C) 2001 Elsevier Science B.V. All rights reserved.