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A 430 m3 full-scale anaerobic sequencing batch reactor has been operating continuously for the last two years at the Oklahoma State University Swine Research and Education Center. In August of 2008 the digester was started using a cold start technique. Startup of the reactor was accomplished without the use of a seed sludge only dilute swine manure as received from the pit recharge swine buildings. The ASBR was initially operated at a minimum temperature of 23C, 20 day HRT, and one cycle per day. After one year of operation, the HRT was incrementally reduced from 20 days to 5 days, and the cycles per day was increased from one to two. Effluent and mixed liquor sampling indicate that startup without the use of seed sludge is possible. Reactor stability was maintained during the two year startup period and no pH adjustments were required. Operational parameters have been examined with regard to settling, solids retention, and mixing within the reactor.