ABSTRACT
The external surface is the location of the majority of the bacteria associated with rotifers, since the number of bacteria culturable from homogenised rotifers by the spread-plate method was comparable to that visible on the external surface of the rotifers by scanning electron microscopy. Several methods of decontaminating rotifers were investigated. Most of the chemical agents tested were toxic to rotifers or were ineffective in reducing the rotifer bacterial load. A method is described whereby ultra-violet radiation caused a >99% reduction in the bacterial load without any apparent effect on the rotifers themselves.
