Metabolisable energy content of diets based on oats grain

Abstract

The metabolisable energy (ME) content of a range of oats-based diets, encompassing a wide range in dry matter digestibility of oat grain, was measured at maintenance in sheep. Dry matter digestibility was 66-82% and ME content was 11.4-15.9 MJ/kg DM for the range of oats-based diets studied. Chaffed lucerne hay, used as a control diet, had a dry matter digestibility of 61% and ME content of 9.7 MJ/kg DM. The ratio of ME to digestible energy content of oats diets was 0.88, compared with 0.81 for chaffed lucerne hay. The difference between the diets based on oats grain and chaffed lucerne hay was accounted for by increased urine energy and nitrogen loss on the lucerne diet and not by reduced methane output on oats-based diets. Cell wall organic matter and lignin content of the oats-based diets were strongly correlated with diet digestibility (r2 = 0.79-0.90).