Effect of food intake on productive variables of two species of cladocera, under laboratory conditions

Objective. Assess the effects of different types of food intake on the productivity of Diaphanosoma sp. and Alona sp. under laboratory conditions. Materials and methods. Young Diaphanosoma sp. and Alona sp. were planted in 20 L aquariums at a density of 6 org L-1 and maintained with constant aeration and a photoperiod 12:12 (light: dark). The organisms were fed with Saccharomyces cereviseae and Chlorella vulgaris at a concentration of 4 x 105 cells/ml in three combinations: 1. C. vulgaris, 2. S. cereviseae 3. C. vulgaris + S. cereviseae); 3 replicas were carried out for each treatment. To determine the population density, every 3 days over a 27 day period, the concentration of individuals per ml was measured using a Bogorov camera. Results. The best results were obtained in treatments with microalgae and yeast, with values of TCE=0.1323±0.07 and 0.1598±0.04 days-1, R=0.010±0.004 and 0.019±0.01 org ml-1 days-1, TD=5.2±0.5 and 4.3±0.38 days for Diaphanosoma sp., and Alona sp., respectively, but without significant differences (p>0.05). Conclusions. The mixed diet of yeast and microalgae produced greater productive efficiency in the studied species, constituting an alternative source of live feed for aquaculture.