Optimum Fertilizer Media and Plant Substrates: (Musa paradisiaca L. Peels, Carica papaya L. Peels and Brassica oleracea var. capitata L. Leaves) for the Growth of Freshwater Rotifer (Brachionus calyciflorus Pallas, 1766)

The aim of this study was to search for a cheap source for the mass production of Brachionus calyciflorus Pallas, 1766 which is a good substitute for artemia in the culture of C. gariepinus hatchlings. Poultry manure (1.25 g/L), soya bean (1.25 g/L), groundnut cake (1.25 g/L) and single super phosphate (0.04 g/l) were used exclusively and in combinations as fertilizer media in the culturing of Brachionus calyciflorus Pallas, 1766 used in feeding C. gariepinus hatchlings. The four fertilizer media were combined to give four treatments with two replicates. Three fresh plant substrate (Carica papaya L. Peels, Musa paradisiaca L. peels and Brassica oleracea var. capitata L. leaves) were introduced into treatments labeled A (Poultry manure, soya bean, groundnut cake, single super phosphate and banana pills), B (Poultry manure, soya bean, groundnut cake, single super phosphate and Carica papaya L. Peels), C (Poultry manure, soya bean, groundnut cake, single super phosphate and cabbage slice) with D(Poultry manure, soya bean, groundnut cake, single super phosphate) as the control. A total of 20 Individuals/mL of Brachionus calyciflorus Pallas, 1766 were inoculated into each treatment and the culturing lasted for 12 days. At the end of the culturing period, the best doubling time (tD) were observed in treatment A and B with a doubling time of 2.89 on the 10th day.

Result of the study showed medium B and C to be sig. different (P< 0.05) and performing better than A and D in the early stages of the study. There was an initial lull in production using the C medium, as it had the least performance. By day eight, it had picked up and there was no sig. difference (P>0.05) in production of B. calyciflorus Pallas, 1776 using the four culture media. Thus any of the media can be used for mass production of B. calyciflorus. Use of media B and C is however, recommended because they had a higher carrying capacity and can sustain production over a longer period using a giving quantity compared to the other two media.