Barley feed fractions from integrated ethanol-starch process in diets of pigs

Abstract

The nutritive value of feed fractions of barley obtained from integrated ethanol-starch production was evaluated in a feeding trial and five digestibility and balance trials with growing pigs. The products examined were barley protein, (375 g CP/kg), barley fibre (166 CP and 653 NDF), barley molasses (298 CP) and distillers solubles (333 CP); their respective digestibilities for OM were 0.895, 0.633, 0.864 and 0.834 and for CP 0.910, 0.577, 0.809 and 0.851. Barley protein fortified with pure lysine gave a nitrogen balance similar to that of the isonitrogenous soybean-barley diet. In the growth trial, one third and two thirds of soybean meal protein were replaced with barley protein and barley was replaced with 200 g/kg barley fibre or processed fibre. There was no significant difference in performance between the control and treatment groups, the mean growth rate being 795 g/d and the feed conversion rate 2.9 FU/kg gain. Carcass quality was inferior (P<0.05) in pigs fed barley protein but higher in pigs receiving barley fibre diets. Hydrothermal or multienzyme treatments of barley fibre did not improve its feed value for growing pigs. The overall results of these experiments indicate that the feed fractions, rich in protein have good potential as protein supplements in pig diets. The satisfactory feed conversion when barley fibre was used as an energy source was in line with the results of the digestibility trial.