Blood Chemistry and Enzyme Activity of Oreochromis niloticus (Linnaeus, 1758) Fed Dietary Processed Lemna paucicostata (Hegelm) as a Replacement for Soybean Meal

This study evaluated the effect of replacing Glycine max with processed Lemna paucicostata on haematological parameters and enzyme activity of Oreochromis niloticus. The processing methods employed were blanching and sun-drying. Nine diets (D1-D9) were formulated using the least cost feed formulation software. Soybean meal was replaced by blanched and sun-dried L. paucicostata at 25%, 50%, 75% and 100% each. 27 nets measuring 1m2 each were used in outdoor concrete ponds of 5m x 3.5m (l × b) and depth of 1.5m each. Ten fingerlings of O. niloticus were stocked per Hapa and fed three times daily at 5% body weight. The fish fed 75% blanched L. paucicostata obtained the best concentration of the packed cell volume (32.01%) in the blood while a poor concentration of 27.01% was observed in the fish fed 100% blanched L. paucicostata. The fish fed 75% blanched L. paucicostata and 50% blanched L. paucicostata gave higher total enzyme activities of 4,675.13(TU) and 4,648.06(TU), respectively. While the fish fed 100% blanched L. paucicostata gave the lowest value of 3,558.33(TU). The digestive enzyme activities were observed to be the main factors that helped the experimental fish to digest the blanched and sun-dried Lemna paucicostata efficiently.