Annual methane emission from pig manure in Korea is less than the estimate of Intergovernmental Panel on Climate Change.

OBJECTIVE: An accurate estimation of methane (CH4) emissions from pig manure is important to effectively manage greenhouse gases from pigs. The present work aimed to estimate annual CH₄ emissions from market pig manure in Korea based on the energy utilization of growing pigs and to compare the values with the estimate of Intergovernmental Panel on Climate Change (IPCC). METHODS: Data on energy utilization in growing pigs fed corn-soybean meal-based diets were obtained from 4 experiments reported in 3 research articles. The average body weight (BW) in each experiment was 30.8, 64.3, 73.8, and 74.5 kg, respectively. The Gompertz model was employed to estimate BW of the pigs based on age. Daily metabolizable energy (ME) intake was calculated based on BW. The daily gross energy (GE) output consisted of daily fecal and urinary GE output was calculated as the difference between daily GE intake and daily ME intake. Daily volatile solid (VS) excretion from market pigs was calculated based on daily GE output and dietary organic matter content using the IPCC equation. The annual CH4 emissions were calculated based on daily VS excretion using the IPCC model. RESULTS: The ME:GE of the diets ranged from 0.84 to 0.91. The representative daily GE output of a market pig was 24.4 MJ/d, which corresponded to the BW of 37.9 kg at 85.1 d of age. The daily VS excretion of a market pig was 0.14 kg/d, and the annual CH₄ emission from market pig manure was 3.80 kg/yr (standard error = 0.09) in Korea, which was less (p<0.001) than 8.0 kg/yr suggested by the IPCC. CONCLUSION: Based on the actual energy utilization of growing pigs in Korea, the annual methane emission from market pig manure was 3.80 kg/yr which is less than the estimate suggested by the Intergovernmental Panel on Climate Change.