Abstract

PETERS. D, Ramón R.; MORALES. A., Ever D.; MORALES, S, Nerva M.  and  HERNANDEZ. R., Jim L.. Feeding Quality Evaluation of Lemna obscura Meal as Ingredients in the Elaboration of Food for Red Tilapia (Orechromis spp.). Rev. Cient. (Maracaibo) [online]. 2009, vol.19, n.3, pp.303-310. ISSN 0798-2259.

The present work was carried out with the purpose to evaluate the nutritional quality of duckweed (Lemna obscura) meal as ingredient in the food elaboration for red tilapia (Oreochromis spp.). Three diets were prepared with inclusion levels of 15% (diet A), 25% (diet B) and 35% (diet C) and a control diet free of Lemna meal. The diets were isocaloric and isonitrogenous with 30% of protein. Furthermore, commercial diet (diet D) with 40% protein was used to compare with experimental diets. The fingerlings were fed during 10 weeks consecutive and fourteen days, were evaluated the most important parameters as weight gain, consumed food, feed convertion ratio (FCR) and the protein efficiency ratio (PER). The statistical comparison revealed that there were no significant differences (P>0.05) in the values of final results of convertion among diets control, A, B, C and D. In relation to weight average final there were significant differences (P<0.05) among the fish fed with the diet B with respect to the control diet and commercial diet. There were no significant differences among experimental diets (P>0.05). This study showed that diet with inclusion level 25% resulted to be more efficient in how much to the evaluated parameters that the diet control. The excesses of Lemna grown in the Maracaibo lake or cultivated can be used as meal in the diets for red tilapia and represents one alternative to reduce the feeding costs, as long as it used in combination with other ingredients of high protein content.

Keywords : Lemna; diets; tilapia; Oreochromis spp.