Abstract:
This research was divided into 2 parts. The first part was aimed to study the effect of water reduction according to the clean technology principle on pig health (pig weight). The second part was aimed to study the effect of solid contents in the performance of the combined 2-stage reactor. The finishing pigs were fed in 2 separated housings. There were 20 pigs each. The washing procedure in controlled group was as usual. The procedures following the clean technology (CT) guidelines in the other housing was called clean technology (CT) group. It was found that the control group consumed the water for dairy use and for washing higher than the CT group for 17.4 and 56.2%, respectively. However, the water consumption for drinking in the control group is less than the CT group for 32.0%. In feeding for 105 days before sale, the pig weight in the control group was in the range of 92 132 kg/head. That in the CT group was in the range of 97 136 kg/head. It was found that the total solid, volatile solid and suspended solid in wastewater from the control group were 11,200 15,600, 5,000 7,250 and 7,300 8,390 mg/L, respectively. Those from CT group were 22,340 31,360, 9,860 17,765 and 12,480 18,139 mg/L, respectively. The methane production rates from the combined 2-stage reactor at steady stage during experimental day of 81-90 at total solid contents of 5, 2.5, 1 and 0.5 were 3.46±0.04, 2.03±0.01, 1.13±0.02 and 0.48±0.02, respectively.