Cysts, in particularArtemiacysts, are incubated the in a hatching medium so that a portion of the cysts hatch and release free swimming live food organisms. The free swimming live food organisms have subsequently to be separated from the cysts which have not hatched. Before incubating the cysts, magnetic particles are applied onto the cysts so that these cysts can be attracted magnetically, in particular in the liquid hatching medium. This enables to separate the unhatched cysts and the empty cyst shells, coated with the magnetic particles, effectively from the free swimming live food organisms which do not have magnetic particles applied onto their outer surface. The invention also relates to the coated cysts.一種卵囊，尤其是豐年蝦卵囊，被培育於孵化培養基因而一部分卵囊孵化並釋出自由泳動活體飼料有機體。此自由泳動活體飼料有機體隨後必須與未孵化卵囊分離。培育此卵囊之前，將磁性顆粒施予至卵囊上因而此等卵囊可被磁力吸引，尤其於液體孵化培養基。其能夠有效地自未被覆磁性顆粒於其外表面之自由泳動活體飼料有機體分離出被覆磁性顆粒之未孵化卵囊及空卵囊殼。本發明亦係關於此經被覆卵囊。
