DIGESTIBILITY AND PERFORMANCE OF WATER HYACINTH MEAL IN THE DIETS OF Clarias gariepinus (BURCHELL, 1822). | DIGESTIBILIDAD Y COMPORTAMIENTO DEL BAGRE AFRICANO (Clarias gariepinus; BURCHELL, 1822) CON DIETAS DE JACINTO DE AGUA

English. Water hyacinth meal (WHM) as an alternative protein source was investigated in this study. Whole water hyacinth plant meal (WPM), water hyacinth leaf meal (WLM) and soya bean meal (SBM) were used to compound three isoproteic (40% crude protein) fish diets. Catfish of 11.2 ± 0.3g average weight were used for the 70-day digestibility study. Data were collected forthnightly on fish growth performance and water qualities (dissolved oxygen, pH, ammonia and temperature). Fish, feeds, and faecal wastes were analyzed. Fish fed SBM-based diet had superior performance over those fed WHM-based diets with respect to Mean weight gain (MWG), Specific growth rate (SGR), Protein efficiency ratio (PER), Feed conversion ratio (FCR), Nitrogen metabolism (Nm) and digestibility coefficients (ADC).  Fish fed all diets exhibited marginal difference in total feed intake but growth performance and nutrient utilization were significantly higher in fish fed WLM than fish fed WPM probably as a result of high fibre content present in WPM. Extremely low value of ammonia was recorded in water under WPM treatment (0.18±0.06 mg/l) while water under WLM and SBM treatment had significantly higher values of ammonia 0.46± 0.13 mg/l and 0.71± 0.10 mg/l respectively. These observations may be due to the presence of significantly higher fibre content in the WPM than other meals. Consequently this could be responsible for its poor digestibility values but high potential for waste water purification. Water hyacinth leaf meal (WLM) would therefore serve a better option for adoption in ensuring maximum utilization potentials of the aquatic plant both for profitable and sustainable fish production.

Spanish; Castilian. Se evaluó el uso de harina de jacinto de agua (WHM) como una fuente alternativa de proteína. Harina de planta completa (WPM), de hoja (WLM) y pasta de soya (SBM) fueron empleados para elaborar 3 dietas isoproteicas (40% proteína cruda). Se emplearon bagres de 11.2 ± 0.3g de peso para un estudio de digestibilidad de 70 d. Se recolectó información en crecimiento y calidad del agua (oxígeno disuelto, pH, amonía y temperatura). Se analizaron los peces, alimentos y residuos fecales. Los peces alimentados con SBM tuvieron un mejor desempeño que aquellos alimentados con WHM. Los consumos fueron marginalmente diferentes, pero el crecimiento y utilización de nutrientes fue mayor en WLM que en WPM probablemente como resultado del alto nivel de fibra de WPM. Se observó un nivel muy bajo de amonia en WPM en comparación con WLM y SBM (0.18±0.06, 0.46± 0.13 y 0.71± 0.10 mg/l respectivamente). La harina de hoja de Jacinto de agua puede ser una buena opción rentable para la producción de peces.Â