The effect of density on the intake of dried forage pellets by young ruminants

Abstract

SUMMARYDried grass pellets of high density (1·3 g/ml) were fed ad libitum to British Friesian male calves 5 to 7 mo old (Experiment 1) or 2 to 5 mo old (Experiment 2). All eight animals in Experiment 1 and eight out of 12 in Experiment 2 were fitted with rumen fistulae. In some subperiods of both experiments, pellets were broken down in water and administered as a slurry directly into the rumen at a level equivalent to approximately one-third that of voluntary intake. Intake per os was significantly reduced by this treatment but total intake (per os+per rumen) was not affected.In Experiment 3 pellets of high (1·24 g/ml) or medium (1·14 g/ml) density were fed ad libitum to 40 9-mo-old Suffolk × Scottish Halfbred wether sheep, either alone or with access limited to 3 hr a day, in which case chopped hay was always available. Pellet density did not affect total intake, but when offered as supplements to hay the consumption of medium-density pellets was higher than that of high-density pellets. In all three experiments animals required 2 or 3 weeks to reach maximum intake of pellets. Over the 42 days of Experiment 3 the proportion of pellets in the feed consumed by animals given pellets as supplements to hay increased from 60 to 80%.