In an experiment conducted on 96 male lambs (3 groups of 32) fattened from
19 to 39 kg on diets containing various levels of crude protein (16 vs 14%
in DM) and metabolisable energy (12.4 vs 12.7 MJ/kg DM) no significant diff
erences in daily liveweight gain were noted (272 to 279 g). Feed utilisatio
n was similar in all groups. A tendency (P>0.05) towards somewhat better pr
otein utilisation (586 vs 674 g/kg) from isoenergetic rations was observed
in lambs fed rations containing 14% CP than in those receiving 16% CP.
Slaughter performance, morphological and chemical composition of the lambs'
empty body weight, protein (18.3-19.8%) and fat (17.6-21.4%) deposition in
empty body gain did not differ significantly among groups.
Differentiating the level of protein (103-163 g/kg DM) in concentrates used
to feed suckling lambs had no effect on liveweight gain during fattening (
262-288 g daily).