21 February 1997

Quality protein in, better lambs out

OFFERING ewes better quality protein in the last few weeks of pregnancy produces bigger lambs and reduces mortality.

Ewes fed a ration with 30% digestible undegradable protein (DUP) alongside ad lib hay in a trial at Harper Adams gained almost 2kg more than ewes on a 25% lower DUP diet, according to trial sponsor, Bibby.

The trial compared 40 twin-bearing Dorset cross ewes split into two groups and weighed every two weeks before lambing and again at lambing.

Lamb litters produced by ewes on the high DUP ration were 0.5kg heavier – a rise of 0.25kg a lamb – than those lambs from ewes on the lower DUP diet.

Using SAC costings, which show that each extra kg of lamb birth weight equates to a 10.6% cut in mortality, the high DUP diet is worth £93/100 ewes in extra lamb returns with lambs costed at £34 a head, says the company.n