Phytoplankton as Rich Food for <i>Oreochromis niloticus</i> (LINN.) in Nigeria

Abstract

Scenedesmus quadricauda could be produced in large amount as alternative fish food. Four batch outdoor cultures using three 10m3 concrete tanks fed with baker's yeast (Saccharomyces cerevisaeM)(yist), inorganic fertilizer (inorg.) and chicken manure (ckm) were carried out to mass produce S. quadricauada. Average peak cell densities of 11.73 x 106, 15.00 x 106, 15.02 x 106 S. quadricauda cells per mL were realized using inorg, yist and ckm, respectively. Gross primary production, carbon and energy analysis put ckm above yist and inorg with average values of 36.4, 20.8 & 7.6 kgO2/ha/d, 6.7, 6.7 &2.2 kgC/ha/d and 0.38, 0.24 & 0.07 kJ/ha/d, respectively. Plankton productivity measured through chlorophyll a yielded 6.434, 4.101 and 0.982 kg/ha/d for ckm, yist and inorg, respectively, with perfect correlation (r =1.0) between O. niloticus growth and Chl-a. ANOVA test indicated highly significant (p<0.001) growth of S. quadricauda cultivated using ckm and yist in comparison with inorg but non-significant difference (p>0.05) between ckm and yist in cell density, primary production and chl-a analysis.

Keywords: Oreochromis niloticus, Scenedesmus quadricauda, Algal nutrients, Mass culture

Tropical Freshwater Biology Vol. 16 (1) 2007: pp. 89-98