Composition and nutritive value of some grasses, plants and aquatic weeds tested as diets

The composition and nutritive value of different diets, namely the aquatic weeds—Hydrilla verticillata (L.f.) Presl., Lemna gibbs (L.) Pistia stratiotes (L.), grasses—Guinea grass Panicum maximum Jacq., Napier grass Pennisetum purpureum Schum. and plants—sweet potato leaves Ipomaea batatas L. and tapioca leaves Manihot utilissimus Pohl. were determined and compared. The diets contained 13.5 to 30.48% protein; 1.89 to 9.60% fat; 3.94 to 23.13% ash; 5.42 to 26.70% fibre and 24.87 to 46.27% carbohydrate. Most of the minerals determined in the aquatic weeds were higher than those in grasses and plants. The feeding of Hydrilla, Napier grass and tapioca leaves to grass carp Ctenopharyngodon ideltus (V.) showed a different growth rate and the results obtained indicated the superiority of Hydrilla diet over Napier grass and tapioca leaves.