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Influence of straw quality and level of concentrate in a completely mixed diet on intake and growth rate in steers

Published online by Cambridge University Press:  02 September 2010

E. R. Ørskov
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
G. W. Reid
Affiliation:
Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
M. Kay
Affiliation:
Scottish Agricultural College, School of Agriculture, 581 King Street, Aberdeen AB9 1UD
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Abstract

Three types of straw were used, a spring barley (variety Corgi) untreated (UC), ammonia-treated Corgi (AC) and an ammonia-treated winter wheat (variety Longbow) (AW). Each straw was included in a complete diet containing either 350 (L), 450 (M) or 550 (H) g/kg straw. The other principal ingredients were rolled barley, molassed sugar-beet pulp and fish meal. Hereford cross steers approximately 16 months old and weighing 350 kg live weight were given the diets ad libitum in both a main trial lasting 80 days, to assess intakes, live-weight gains and food efficiency, and in a subsidiary trial to measure in vivo apparent digestibility.

The live-weight gains during 80 days for steers given the UC diet at L, M and H inclusion were 117, 102 and 0·70 kg/day respectively. The respective live-weight gains for AC were 1·32, 1·27 and 1 02 kg/day and for AW 1 ·26, 1 ·20 and 0·95 kg/day.

While experimental comparisons were terminated at 80 days when the first steers were slaughtered, all except five with the lowest growth rate reached the target fat class for slaughter before 6 months on the diets. While differences in intake and performance between steers given the straws closely reflected differences in degradation characteristics determined by in sacco measurements, the increase in in vivo apparent digestibility between untreated (0·510) and treated (0·545) was small. It is concluded that a large proportion of high quality or treated straw can be incorporated and utilized in diets for finishing cattle.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1991

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References

REFERENCES

Brockway, J. M., McDonald, J. D. and Pullar, J. D. 1977. Calorimetric facilities at the Institute and the techniques employed to measure energy metabolism. Annual Report, Rowett Research Institute, Vol. 33, pp. 106119.Google Scholar
Davidson, J., Mathieson, J. and Boyne, A. W. 1970. The use of automation in determining nitrogen by the Kjeldahl method, with final calculations by computer. Analyst, London 95: 181193.CrossRefGoogle ScholarPubMed
Istasse, L., Smart, R. I. and Ørskov, E. R. 1986. Comparison between two methods of feeding concentrate to sheep given a diet high or low in concentrate with or without buffering substances. Animal Feed Science and Technology 16: 3749.CrossRefGoogle Scholar
Meat and Livestock Commission. 1975. Progress on beef carcase classification. Marketing Meat Trade Technical Bulletin No. 22. Meat and Livestock Commission, Bletchley.Google Scholar
Ørskov, E. R. and McDonald, I. 1979. The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage. Journal of Agricultural Science, Cambridge 92: 499503.Google Scholar
Ørskov, E. R., Reid, G. W. and Kay, M. 1988. Prediction of intake by cattle from degradation characteristics of roughages. Animal Production 46: 2934.Google Scholar
Ramanzin, M., Ørskov, E. R. and Tuah, A. K. 1986. Rumen degradation of straw. 2. Botanical fractions of straw from two barley cultivars. Animal Production 43: 271278.Google Scholar
Reid, G. W., Ørskov, E. R. and Kay, M. 1988. A note on the effect of variety, type of straw and ammonia treatment on digestibility and on growth rate in steers. Animal Production 47: 157160.Google Scholar
Tuah, A. K., Lufadeju, E., Ørskov, E. R. and Blackett, G. A. 1986. Rumen degradation of straw. 1. Untreated and ammonia-treated barley, oat and wheat straw varieties and triticale straw. Animal Production 43: 261269.Google Scholar