Potential Use of Water Hyacinth (Eichhornia Crassipes), to Reduce Production Cost in Tilapia Culture at Small and Median Scale

Abstract

Tilapia farming is increasing in the US, Mexico and other countries; but anywhere, the cost of food is the big problem. Therefore, to reduce production costs, the water hyacinth aquatic plant, was used as a food supplement. Dehydrated water hyacinth was assorted with cane molasses and anaerobically fermented with (Lactobacillus sp.). The fermented product was mixed with cornmeal and commercial food (Purina®), at proportions of 30-20-50 respectively. Then mixture was extruded and dried, to be used as a feed supplement for tilapia. Juveniles tilapia between 5-7 g were obtained from a commercial hatchery and fed with Purina®, until fishes reached 24-26 g; then, tilapias were separated into two groups; the experimental and the control groups. The experimental group, 40 tilapias, was transferred to a 4032 L pond, while control group,15 tilapias were distributed in 5 ponds of 300 L; in this way, the socking density was around (10 fish/m3) in all ponds. The experimental group was fed with water hyacinth supplemented food, while the control group with Purina®. Tilapia from both groups were weighed every 2 weeks for 3 months; moreover, the water quality parameters pH, O2, T (oC), TSS and total ammonia were recorded in all the ponds. To know the tilapia growth from both groups, several growth parameters, such as: weight gain, relative growth rate, feed conversion ratio and specific growth rate were calculated. Results showed that tilapia weight gain fed with supplemented water hyacinth food, was 8.6 % higher than tilapias fed, with Purina®. Also, the food cost of tilapias fed with water hyacinth supplemented feed, were 15.37 % lower than tilapia fed with Purina®. Therefore, it can be concluded that tilapia aquaculture at small and medium scale, can developed satisfactorily using water hyacinth supplemented feed.