Methane production of growing and finishing pigs in southern China

Methane from enteric fermentation and manure decomposition from livestock contributes to greenhouse gas (GHG) emissions. Research on CH4 production from enteric fermentation has mainly focused on ruminant livestock. However, CH4 production from enteric fermentation in pigs may be important due to the large global pig population. This experiment measured enteric CH4 from growing and finishing pigs in China. Five 58.9 ± 1.15 kg and five 89.4 ± 0.85 kg Duroc × Landrace × Large Yorkshire female pigs were randomly selected from a commercial farm in Shenzhen, Guangdong province (China). The pigs were transferred to individual 2.0 m × 1.0 m × 1.2 m respiration chambers located on the same farm and continued to be fed the commercial diets of their respective weight group on the farm. After 3 d of adaptation to the respiration chambers, daily CH4 emissions were measured from the 10 pigs for 3 d. The CH4 production of the 60 and 90 kg pigs was 1.13 and 2.01 g pig/d, respectively, with that of 90 kg pigs higher than the 60 kg group (P<0.05). When the values are adjusted/kg DM feed intake (i.e., 0.70 g/kg DM versus 0.82 g/kg DM) and per kg body weight (19.01 g/kg versus 22.47 g/kg) for the 60 and 90 kg groups, there were no differences. Using these values, estimated annual CH4 production from the 60 and 90 kg pigs was 0.41 kg and 0.73 kg, respectively, values which are lower than the 1 kg pig/year adopted by the Intergovernmental Panel on Climate Change. The high variation in CH4 emission among our pigs, and those in the literature, suggest that differences in CH4 emission exist among pigs within the same herd housed under similar nutritional and husbandry management. rticle is part of the special issue entitled: Greenhouse Gases in Animal Agriculture – Finding a Balance between Food and Emissions, Guest Edited by T.A. McAllister, Section Guest Editors; K.A. Beauchemin, X. Hao, S. McGinn and Editor for Animal Feed Science and Technology, P.H. Robinson.