Reproductive rate of Brachionus calyciflorus under the influence of salinity, temperature, feed type and feed concentration

Abstract

The impact of salinity, temperature, feed type and feed concentration on reproductive rate ‘r’ of Brachionus calyciflorus were examined in the present study. Three salinity levels (0.5%, 5.0% and 10.0%) and three temperature regimes (25 ± 1 oC, 29 ± 1 oC and 35 ± 1 oC) were evaluated. Four microalgal diets, Chlorella ellipsoidea, Ankistrodesmus convolutes, Scenedesmus protuberans and Chlorococcum infusorium at a concentration of 1x 106, 2x 106, 3x 106, 4x 106, 6x 106, 8x 106, 10x 106 and 12x 106 were tested in the experiment. The findings showed that all these parameters have significant influence on reproductive potential of Brachionus calyciflorus. The optimum salinity and temperature required for rmax for B. calyciflorus were of 0.5% and 29 ± 1 oC, respectively. The intrinsic rate of reproduction of B. calyciflorus for the best salinity x feed concentration with C. ellipsoidea (8 x 106 cell mL-1), A. convolutus (6 x 106 cells mL-1), C. infusorium (8 x 106 cells mL-1) and S. protuberans (4 x 106cells mL-1 ) at the optimal salinity and temperature were 1.91, 1.83, 1.77 and 1.62. Based on the study, the maximum reproductive potential of B. calyciflorus can be achieved by feeding with C. ellipsoidea at a salinity and temperature of 0.5% and 29 ± 1 oC, respectively for the larviculture of fishes.