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The effect of urea on digestion and voluntary intake by sheep of diets supplemented with fat

Published online by Cambridge University Press:  02 September 2010

E. R. Ørskov
Affiliation:
The Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
R. S. Hine
Affiliation:
The Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
D. A. Grubb
Affiliation:
The Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
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Abstract

Two experiments were conducted to determine whether the depression in fibre digestion caused by inclusion of fat in diets could be alleviated by addition of urea and whether the physical incorporation of fat in itself caused a reduction in rate of fibre digestion.

Early-weaned lambs were given dried grass containing either 65 or 130 g/kg of tallow with or without 15 g/kg of urea. Fat inclusion caused a linear depression in intake and fibre digestibility. The depression in intake was partly alleviated by urea inclusion, but urea did not affect fibre digestibility.

The physical incorporation of fat into dried grass did not in itself appear to depress rate of digestion. It is suggested that if coating of feed particles is important then this would be due to non-esterified fatty acids in the rumen and not to triglycerides.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1978

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References

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