The effects of roughage type on the daily patterns of feed intake and eating behaviour in young sheep

SUMMARY The effects of roughage type on the daily patterns of feed intake and eating behaviour were investigated in young sheep, individually housed. A total of 24 young sheep were allotted in 4 equal groups according to the roughage type (barley straw, corn silage, alfalfa hay and sugar beet pulp) distributed ad libitum 6 times a day in 4 hours meal intervals. Roughage intake and eating behaviour were analysed using a camera recording system for 24 hours for 7 days. The intake of barley straw (characterized by the highest crude fiber and NDF contents) was significantly depressed compared to the other roughages leading to a significantly decreased body weight and sheep spent significantly less time and low frequently eating and they have presented significantly longer resting periods than others. Sheep have eaten significantly more alfalfa hay (crude fiber: 30.1% and NDF: 50.0%) than the other roughages, have spent frequently and long time eating and have rested frequently. In the group fed with sugar beet pulp (crude fiber: 17.5% and NDF: 46.0%), animals have preferred shorter but more frequent meals than with corn silage (crude fiber: 25.2% and NDF: 64.0%) and alfalfa hay including after midnight whereas sheep from the other groups were sleeping. These results show that the NDF and moisture contents of the roughage directly affected the ingestibility leading to some changes in the eating behaviour, particularly in the frequency and quantity of meals and in the duration of resting periods.