Investigation on Suitability and Safeness of Water hyacinth for Animal Feed, from Lake Ziway

Abstract

Water hyacinth is a free-floating aquatic plant native to the Amazon Basin in South America and the most dangerous and worst aquatic plant in the world including Ethiopia. The objective of the current study was to evaluate water hyacinth found in Lake Ziway for its suitability and safe as animal feed. Suitability of the water hyacinth was determined based on its nutrient content, while safety was determined based on the level of selected heavy metals, and pesticides. Three sites were selected for sampling purposively based on the types of land use and potential sources of water pollution around the Lake. Water hyacinth samples were collected from the selected sites and the level of selected heavy metals, 21 organochlorine, and 14 organophosphate pesticides were analyzed using atomic absorption spectrometry and Gas Chromatography-Mass Spectrometry (gc-ms), respectively. The proximate analysis in the water hyacinth were also determined using the standard method of analysis. The results obtained demonstrate that the level of heavy metals found the ranged from nd to9.0 mg/Kg for cadmium; nd to 30.44 mg/Kg for chromium; 118.1 to 518.8 mg/Kg for manganese; 6.78 to 57 mg/Kg for copper; 34.28 to 884.19 mg/Kg for iron; 2.84 to 37.02 mg/Kg for nickel nd to 21mg/kg for lead and 25.67 to 89.9 mg/Kg for zinc. All pesticides levels were below the limits established by European council regulation for plants used as animal feed which is <0.001mg/Kg.  The proximate analysis of the water hyacinthsamples of the leaves parts was moisture content 9.32%, crude protein 18.03%, crude fat 1.42%, crude ash 17.04%, crude fiber 31.04% carbohydrate 22.30%and energy 174 Kcal. The result of the stem revealed the presence of 3.96 moisture content, 2.17% crude protein, 0.47% crude fat, 5.23% crude ash, 6.70% crude fiber, 81.47% carbohydrate, and 338.79 Kca energy. Based on the results of this study, water hyacinth in the Lake Ziway can be potentially used for animal feed.