Abstract :
The influence of whole, crushed and ground barley and oats on intake, performance and
carcass characteristics of lambs was examined. A comparison of diets was conducted with
individually-fed male and female lambs in six groups. The study was repeated in three
successive years (1995–1997) using the same experimental design. A total of 192 lambs of
a mean initial age of 74 days (SD 13.0) and live weight 20.6 kg (SD 4.54) were daily fed their
respective concentrates, 72 g dry matter (DM)/kg metabolic live weight (kgW0.75), for 98
days from weaning to slaughter. Hay was provided ad libitum.
The lambs adapted more quickly to diets containing barley than to those containing
oats. Compared to oats, the total daily DM intake was higher on barley (1162 vs. 990 g
DM/lamb, 89 vs. 78 g DM/kgW0.75, P < 0.001). Hay consumption was significantly lower on
oats than on barley (182 vs. 344 g DM/day, P < 0.001). On oats the lambs experienced energy
and protein deficiencies with their energy and protein intakes being 20% below feeding
recommendations. On the barley diets the energy and protein requirements of the lambs
were satisfied. When processed cereals were offered, there was no increase in the total DM,
energy or protein intakes. Processing did not improve the organic matter digestibility of
barley or oats.
The growth rate (P < 0.01), carcass weight (P < 0.001) and slaughter percentage (P < 0.001)
were higher on a barley diet than on oats. A barley diet resulted in more kidney fat (P < 0.01)
and fattier carcasses. Processing had no positive influence on the live weight gain. On the
contrary, lambs receiving crushed or ground barley or oats had a lower final live weight than
those receiving whole grains (P < 0.001). The utilisation of whole grain was more efficient
than that of processed grain. There were no advantages in processing barley and oats for
the feeding of lambs.
