Bacterial Protein Grown on Natural Gas as Feed for Pigs

Bacterial protein meal (BPM) produced by a mixture of Methylococcus capsulatus (Bath), Alcaligenes acidovorans, Bacillus brevis and Bacillus firmus grown on natural gas, was studied as a protein source for pigs. Three growth trials were conducted, one with weanling pigs (Expt 1) and two with growing-finishing pigs (Expts 2 and 3). In Expt 1, 64 appetitefed weanling pigs (10.4 kg average initial weight) were used to determine the effect of adding BPM (0 g, 40 g, 80 g and 120 g kg^-1) to diets replacing traditional protein feedstuffs on growth performance. During week 0-2, adding BPM to diets increased average daily gain (ADG) (linear P < 0.03). During week 0-2 and week 0-4, the 120 g kg^-1 BPM diet increased (P < 0.01) average daily feed intake compared with the control and the 50 g kg^-1