Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-27T19:18:57.619Z Has data issue: false hasContentIssue false

Cereal processing and food utilization by sheep. 3. The effect of replacing whole barley by whole oats on food utilization and firmness and composition of subcutaneous fat

Published online by Cambridge University Press:  02 September 2010

E. R. Ørskov
Affiliation:
The Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
W. R. H. Duncan
Affiliation:
The Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
Constance A. Carnie
Affiliation:
The Rowett Research Institute, Bucksburn, Aberdeen AB2 9SB
Get access

Summary

1. Forty-eight early-weaned lambs were used in an experiment in which whole barley was gradually replaced by whole oats in order to produce different types of rumen fermentation.

2. The type of rumen fermentation promoted by whole barley did not give rise to excessively soft fat in female lambs; in males, however, some carcasses were unacceptable. An increase in the proportion of propionic acid in the rumen liquor was associated with an increased proportion of odd- and branched-chain fatty acids and a decreased proportion of stearic acid in carcass fat. When the molar proportion of propionic acid in the rumen liquor was above 30%, three out of every five carcasses from the entire male lambs had excessively soft fat.

3. Assessment of food utilization was complicated by lower daily intakes of digestible organic matter (DOM) when more than about 15% of barley was replaced by oats and also influenced by changes in gut contents. With 100% whole barley the mean gut fill was 4·7 kg while with 100% oats it was 9·4 kg.

Assuming a maintenance requirement of 100 kcal metabolizable energy/kg0·75, it was calculated that the digestible organic matter of oats was utilized more efficiently than that of barley to produce empty-body gain. Most of the differences in utilization disappeared if an adjustment was made for differences in gut contents. The results indicate that the maintenance requirement/kg0·75 decreases with increasing gut content.

Type
Research Article
Copyright
Copyright © British Society of Animal Science 1975

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Andrews, R. P. and Ørskov, E. R. 1970. The nutrition of the early weaned lamb. 1. The influence of protein concentration and feeding level on rate of gain in body weight. J. agric. Set, Camb. 75: 1118.Google Scholar
Davidson, I., Mathieson, J. and Boyne, A. W. 1970. The use of automation in determining nitrogen by the Kjeldahl method with final calculation by computer. Analyst, Lond. 95: 181193.CrossRefGoogle ScholarPubMed
Duncan, W. R. H., Ørskov, E. R., Fraser, C. and Garton, G. A. 1974. Effect of processing of dietary barley and of supplementary cobalt and cyanocobalamine on the fatty acid composition of lamb triglyceride with special reference to branched chain fatty acids. Br. J. Nutr. 32: 7175.Google Scholar
Duncan, W. R. H., Ørskov, E. R. and Garton, G. A. 1974. Effect of different dietary cereals on the occurrence of branched chain fatty acids in lamb fats. Proc. Nutr. Soc. 33: 81A.Google Scholar
Fell, B. F., Kay, M., Whitelaw, F. G. and Boyne, R. 1968. Observation on the development of ruminal lesions in calves fed on barley. Res. vet. Sci. 9: 458466.CrossRefGoogle ScholarPubMed
Garton, G. A., Hovell, F. D. Deb. and Duncan, W. R. H. 1972. Influence of dietary volatile fatty acids on the fatty acid composition of lamb triglycerides with special reference to the effect of propionate on the presence of branched chain components. Br. J. Nutr. 28: 409416.Google Scholar
Ørskov, E. R. 1973. The effect of not processing barley on rumenitis in sheep. Res. vet. Sci. 14: 110112.CrossRefGoogle Scholar
Ørskov, E. R. and Fraser, C. 1972. Effect on type of rumen fermentation and digestibility of feeding whole as opposed to processed barley to sheep. Proc. Nutr. Soc. 31: 101A.Google Scholar
Ørskov, E. R., Fraser, C. and Gordon, J. G. 1974. Effect of processing of cereals on rumen fermentation, digestibility, rumination time and firmness of subcutaneous fat. Br. J. Nutr. 32: 5969.CrossRefGoogle ScholarPubMed
Ørskov, E. R., Fraser, C. and McHattie, 1.1974. Cereal processing and food utilization by sheep. 2. A note on the effect of feeding unprocessed barley, maize, oats and wheat on food utilization by early weaned lambs. Anim. Prod. 18: 8588.Google Scholar
Ørskov, E. R. and McDonald, I. 1970. The utilization of dietary energy for maintenance and for protein and fat deposition in young growing sheep. In Energy Metabolism of Farm Animals (ed. Schurch, A. and Wenk, C.), EAAP Publ. No. 13.Google Scholar
Tait, R. M. and Bryant, R. G. 1973. Influence of energy source and physical form of all concentrate rations on early weaned lambs. Can. J. Anim. Sci. 53: 8994.CrossRefGoogle Scholar
Van Es, A. J. H. 1972. Maintenance. In Handbuch der Tiererndhrung (ed. Lenkeit, W., Breirem, K. and Crasemann, E.), pp. 154. Verlag Paul Parey, Hamburg and Berlin.Google Scholar