摘要
The concentration of volatile fatty acids （VFA） determined from a previous study was used to determine the concentration of carbon dioxide （CO2） and methane （CH4） in pig digesta using the model developed for ruminant animals. Digesta from the stomach, cecum and colon of pigs （n = 3 dietl） were used for the determination of VFA. The pigs were fed either a low fiber diet （LFD; 8.3% aNDF） as control, or one of the high-fiber diets （HFD, 22.4% aNDF; D1, D2 and D3） containing 1：2, 1：1 and 2：1, oats to barley ratios, respectively. Results indicated that the concentrations of CO2 and CH4 in pigs fed HFD were, on the average, 25.8 and 24.2%, respectively lower （P 〈 0.05） than pigs fed LFD. Pigs fed the highest oat to barley ratio also showed higher （P 〈 0.05） levels of CO2, （8.3%） and CH4 （5.1%）, compared to the average of the two lower ratios （CO2, 5.3% and CH4, 3.3%）. Molar proportions of VFA, CO2 and CH4 in the gut were in the order of VFA 〉 CO2 〉 CH4, at 53.0%, 28.6% and 18.4%, respectively, and CO2 and CH4 combined represented 47% of total gas.
