Previous studies (e.g. Galbraith, McCulloch, Scalfe, Keeling and Atkinson, 1987) showed that differences in growth and metabolic responses Were obtained in sheep offered diets based on barley compared with those offered sugar beet pulp. At similar intakes of dry matter, barley based diets gave faster live-weight gain and heavier carcasses Which contained greater Weights of crude protein and fat and a higher proportion of fat in the carcass than those based on sugar beet pulp. The differences in fat and protein deposition in the carcass are of particular interest particularly in the context of the greater content of cellulose and hemi-cellulose in the fibre component of sugar beet-based diets. The objective of the present study Was to investigate the response to diets based on sugar beet pulp and supplemented With varying proportions of barley. It was Intended to study the utilisation of the diets which differed in the content of fibre and starch and to provide information on whole body, carcass and selected metabolic and endocrine parameters.