THE FEED VALUE OF A BY–PRODUCT OF THREONINE PRODUCTION BY FERMENTATION IN CATTLE FEEDING

Effects of mother liquor (a by-product of threonine production by fermentation) as a potential feed component for cattle were evaluated in an experiment with Holstein-Friesian steers. Experimental animals were surgically equipped with rumen cannula, and two were equipped with duodenum cannula in order to facilitate sample collection. The experiment consisted of a control and three consecutive experimental phases, each lasting 5 days and separated by 10-day pre-feeding periods. Composition of daily ration of control and experimental phases was identical except for the following supplementations in the different experimental phases: 1.0 kg mother liquor, 1.5 kg mother liquor, and 1.5 kg mother liquor with 1.0 kg molasses, respectively. The experimental supplements increased bacterial activity in the rumen resulting in a significant (P