| Contents |
|
In the Mekong delta water spinach stems are used for making pickles for human consumption, while the leaves are as wastes. This study aimed to utilize them as valuable feeds for the rabbits. Two experiments were carried out in the experimental farm of Cantho University to evaluate the effects of para grass replacement by water spinach leaves (WSL) at levels of 0, 25, 50, 75% (DM basis). Both experiments were complete randomized designs with four treatments, three replicates and two rabbits (balanced for sex) per experimental unit. The first trial was done on growing crossbred rabbits at 8 weeks of age to evaluate feed utilization, growth rate and economic return. The second one was applied on the twelve weeks old rabbits to measure the feed digestibility and nitrogen retention. In Exp. 1, the results showed that the DM intake (g /kg BW) was highest (p<0.001) on the diet with para grass only (WSL0), and lowest on the WSL75 diet (p<0.001). The consumption of OM, NDF, ADF per kg weight gain significantly decreased (p<0.01) with increasing levels of WSL in the diets. The highest daily gain was found for the WSL75 treatment (p<0.01). Lower feed cost and higher income per rabbit resulting in higher profit were found for the WSL50 and WSL75 diets. In the Exp. 2 the apparent digestibility (%) of DM significantly increased (p<0.05) for the diets included WSL, with the highest on the WSL75 diet. The nitrogen retention tended increase with increasing levels of WSL, and the highest on the WSL75 diet. The conclusion was that the replacement of para grass with WSL at levels of 50 and 75% gave the highest daily gain and better economic return.