The physical limitation of rumen capacity frequently restricts forage intake of ruminants to be within that needed to achieve their nutrient requirements for maintenance and production. It has been observed that, in some circumstances, supplementation can enhance the intake of forages, particularly those of low digestibility, while forage intake will reduce at high levels of supplementation, but in ways which are difficult to predict (Weston, 1982).

In a previous trial it was observed that in sheep with an adequate supply of protein, barley supplements caused a decline in hay intake equivalent to 1:1 on a dry matter basis (Eayres el al, 1988). The present study was designed to investigate further the influence of barley and protein supplements on the intakes of hay and straw by sheep.

Thirty two wether sheep (12 months old; Greyface) were placed in individual pens with wire floors and offered chopped hay ad libitum for 21 days in order to allow adaptation to the pens and to a forage based diet.