Alimento complementar adicionado às culturas de Daphnia similis e Ceriodaphnia dubia: efeitos da levedura e da digestão da ração

Over ten years the diet consisting of green algae (Pseudokirchneriella subcapitata) and a suspension of digested fish flake food plus yeast was employed in culturing daphnids, Daphnia similis and Ceriodaphnia dubia in the Aquatic Ecotoxicology Laboratory of CETESB (Companhia Ambiental do Estado de Sao Paulo, SP, Brazil). However, oscillations in the quality of cultures, with adverse effects on adult survival, were attributed to the addition of this complement. For this reason, experiments were conducted to evaluate the supplying of such mixture with the presence and absence of yeast and, later on, with and without digestion of fish flake food. The results showed that a diet including algae and the suspension of non digested (solubilized) fish flake food, permitted the attainment of the quality criteria for Daphnia similis and Ceriodaphnia dubia cultures, established in the respective standard procedures.