Low temperature pre-treatment of domestic sewage in an anaerobic hybrid or an anaerobic filter reactor

The ability of pigs to use nitrogen and energy in Bermuda grass was evaluated in order to assess whether Bermuda grass harvested from spray fields could be fed to pigs as a means to recycle nitrogen. Digestibility of Bermuda grass incorporated into corn-soybean meal diets was evaluated in heavy finishing pigs and gestating sows. Results suggest that Bermuda grass digestibility is negative in animals not adapted to a high-fiber diet. Enzymes improve this digestibility, but even with enzymes, nitrogen digestibility was poor. Pigs fed a diet containing 10% Bermuda grass required a one week adaptation period for maximal digestion; following adaptation, pigs can digest approximately 40% of the energy in Bermuda grass but none of the nitrogen. Feeding Bermuda grass to pigs as a means of recycling nitrogen is thus not recommended.