kinetics data were in line with previously published data in both
mature and growing horses, but did not indicate that threonine was
limiting when the horses were receiving the Basal diet in either
study.
In yearlings, when threonine intake was increased from 94 to
113 mg/kg BW/day, girth circumference increased (Graham et al.,
1994). The study that found improved muscle mass scores when
aged and mature horses were supplemented with threonine and
lysine had a smaller difference in threonine intakes between the
basal and supplemented groups (range 65–102 mg/kg BW/day)