This research aims to study the using cassava pit wastes mixed with cement to particle board walls. The Portland cement type1: fine sand: tap water ratio is equal to 1: 0.5: 0.416 by weight. The ratios of cassava pit wastes to cement are used following: 0.05 0.06 0.07 0.08 0.09 and 0.10 by weight. The cassava pit wastes are crushed by plastic plastics granulators (pass sieve no.4). The casting of particle board walls use the compression machine in room temperature (30 – 35 degree of Celsius) and control 0.75 g/cm3 of density. The TIS 878-2537 standard (cement bonded particle board: high density) is followed to test the properties of particle board wall. Resulting the cassava pit wastes mixed with cement can cast to particle board walls and have good properties especially the thermal insulation property.

This research aims to study the application of cassava fiber. The fibers are taken from cassava and pineapple Head that 3 ratios are used to all of fiber mixing. The fiberboard production use 130°C of temperature with 20 – 50 kg/sq.cm of compressive pressure with 10 minutes per piece of rate. Their fiberboards have 681 – 724 kg/cu.m of density and 7.1 – 7.6 % of moisture. Resulting the CF 05 ratio (cassava: urea is equal to 0.95:0.13) is suitable ratio which has good physical and mechanical properties.

The objective of this study was to determine the effects of malate level and yeast in concentrate on ruminal fermentation and digestibility of nutrients in heifers. The results revealed that rumen fermentation ruminal microorganisms and digestibility of nutrients were significantly different (P<0.05) as affected by malate level and yeast. In conclusion the combined use of concentrate containing high level of cassava chip at 70%DM with malate at 1000 g and yeast at 2000 g in concentrate could improve rumen fermentation and digestibility of nutrients in dairy heifers.