The digestibility of dried microbial cells grown on methanol in diets for growing pigs

Abstract

Summary A microbial cell product was compared with fish meal at three levels of dietary inclusion, using barley as the basal diet. Digestibility coefficients for flash-dried microbial cells (DMC) were calculated to be 0·85 for gross energy and 0·91 for N. Digestible energy (DE) values were 18·8 MJ DE/kg D.M. for DMC and 16·5 MJ DE/kg D.M. for the fish meal. Digestible nitrogen (DN) values were 119 g DN/kg D.M. for the DMC protein and 108 g DN/kg D.M. for the fish meal. The metabolizable energy (ME) values for diets containing DMC were similar to those for diets containing fish meal; ME/DE for diets containing about 16·5% crude protein was 0·96. Microbial N was less efficiently utilized than fish meal N; this was largely attributed to the different contents of nucleic acid N.