A note on the effect of feeding frequency on nitrogen use in growing boars given diets with varying levels of free lysine

Abstract
The effect of frequency of feeding on the efficiency of utilization of L-lysine hydrochloride supplements was studied in 30- to 60-kg pigs. The feeding regimes were: (A) once daily, (B) twice daily, (C) four times daily between 08.30 and 20.30 h, (D) four times daily at 6-h intervals. The response criterion was urinary-nitrogen (N) excretion during 5-day periods. Linear improvements in N utilization were seen in response to lysine supplementation: (a) of a mineralized barley diet (4·0 g lysine per kg to levels of 5·0 and 6·0 g/kg (trial 1)), and (b) of a barley-soya diet (5·5 g lysine per kg to levels of 6·8 and 8·1 g/kg (trial 2)). In both trials the efficiency of N use averaged over the three diets was significantly poorer with once-daily feeding than for the other three treatments, which did not differ significantly from each other.