Biogas was produced by fermentation of pig slurry in a lab. digestor (75 L) at 37 degrees C for 9, 12 and 15 days. A paddle stirrer (47 rpm) was used. The shortening the time to 9 days was of an advantage. The biogas yield was above 60 L/day and the MeH content was quite high (66%). The high concn. of H2S (2952 ppm) was of disadvantage.