Hostname: page-component-cd9895bd7-fscjk Total loading time: 0 Render date: 2024-12-26T07:43:11.418Z Has data issue: false hasContentIssue false

Microbially corrected amino acid composition of rumen-undegraded feed protein and amino acid degradability in the rumen of feeds enclosed in nylon bags

Published online by Cambridge University Press:  09 March 2007

T. Varvikko
Affiliation:
Institute of Animal Husbandry, Agricultural Research Centre (MTTK), SF-31600 Jokioinen, Finland
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. In the previous work (Varvikko & Lindberg, 1985), 15N-labelled rapeseed (Brassica napus), barley, ryegrass (Lolium perenne) and barley straw were incubated in the rumen in nylon bags for 5, 12 and 24 h and microbial nitrogen in the residues was quantified using the feed 15N-dilution method. In the present study, residual amino acids (AA) of these feeds were analysed, and microbially corrected AA of feed origin (feed AA) were estimated as the difference between total residual AA and respective microbial AA, assuming a constant AA composition for the microbial protein.

2. In barley and barley-straw residues, and also in ryegrass incubated in the rumen for 24 h, very large enrich- ment by microbial N and AA-N was found. The microbial enrichment was rather small in rapeseed residues and ryegrass incubated for 5 or 12 h. During the rumen incubation, feed N and AA-N (g/kg feed dry matter (DM)) decreased very clearly in all the feeds, and feed and incubation time effects were always statistically significant (P < 0.001).

3. The slow degradation of essential (E) feed AA compared with the respective non-essential (NE) AA degradation increased the proportion of feed EAA (g/kg determined feed AA) in barley and barley-straw residues. In rapeseed and ryegrass, residual feed EAA: NEAA remained very similar to the original. Branched-chain (Br) AA tended to increase proportionally in all the feed residues, suggesting these AA to be, on average, more resistant against microbial degradation in the rumen than other AA. Similarly, lysine was clearly increased in barley residues. A rumen degradation faster than the average rate caused decreased residual feed glutamic acid in rapeseed; methionine, alanine and glycine in barley; arginine and alanine in ryegrass; and methionine, asparagine and tyrosine in barley straw. Feed and incubation time effects were significant (P < 0.054–001) for feed AA (g/kg determined feed AA) grouped as EAA, BrAA or NEAA, and for most individual AA, as well as for feed AA disappearance (%) and relative amounts (%) of feed AA in the respective residual AA.

4. According to present findings, AA composition of the rumen-undegraded vegetable feed residues may markedly differ, either quantitatively or qualitatively (or both), from their original AA composition. When determining the feed AA composition of nylon-bag residues, the microbial error may be very large with starchy or fibrous feeds of low protein content. The microbial AA do not, however, considerably confuse the AA determination of protein-rich feeds.

Type
Papers on General Nutrition
Copyright
Copyright © The Nutrition Society 1986

References

REFERENCES

Bergen, W. G., Purser, D. P. & Cline, J. H. (1968). Journal of Animal Science 27, 14971501.Google Scholar
Burris, W. R., Bradley, N. W. & Boling, J. A. (1974). Journal of Animal Science 38, 200205.Google Scholar
Chalupa, W. (1976). Journal of Animal Science 43, 828834.CrossRefGoogle Scholar
Craig, W. M. & Broderick, G. A. (1984). Journal of Animal Science 58, 436443.CrossRefGoogle Scholar
Crooker, B. A., Shanks, R. D., Clark, J. H. & Fahey, G. C. (1981). Journal of Animal Science 53, Suppl. 1, 391.Google Scholar
Czerkawski, J. W. (1976). Journal of the Science of Food and Agriculture 27, 621632.CrossRefGoogle Scholar
Ganev, G., Ørskov, E. R. & Smart, R. (1979). Journal of Agricultural Science, Cambridge 93, 651656.CrossRefGoogle Scholar
Kennedy, P. M., Hazlewood, G. P. & Milligan, L. P. (1984). British Journal of Nutrition 52, 403417.CrossRefGoogle Scholar
MacGregor, C. A., Sniffen, C. J. & Hoover, W. H. (1978). Journal of Dairy Science 61, 566573.Google Scholar
March, J. F. (1975). Analytical Biochemistry 69, 420442.Google Scholar
Mathers, J. C. & Aitchison, E. M. (1981). Journal of Agricultural Science, Cambridge 96, 691693.CrossRefGoogle Scholar
Meyer, R. M., Bartley, E. E., Deyoe, C. W. & Colenbrander, V. F. (1967). Journal of Dairy Science 50, 13271332.CrossRefGoogle Scholar
Näsi, M. & Huida, L. (1982). Journal of the Scientific Agricultural Society of Finland 54, 279285.Google Scholar
Purser, D. B. & Buechler, S. M. (1966). Journal of Dairy Science 49, 8184.Google Scholar
Rooke, J. A., Greife, H. A. & Armstrong, D. G. (1984). Journal of Agricultural Science, Cambridge 102, 695702.Google Scholar
Scheifinger, C., Russel, N. & Chalupa, W. (1976). Journal of Animal Science 43, 821827.CrossRefGoogle Scholar
Setälä, J. & Syrjälä-Qvist, L. (1984–5). Animal Feed Science and Technology 12, 1927.CrossRefGoogle Scholar
Stern, M. D., Rode, L. M., Prange, R. W., Stauffacher, R. H. & Satter, L. D. (1983). Journal of Animal Science 56. 194205.CrossRefGoogle Scholar
Storm, E. S. & Ørskov, E. R. (1983). British Journal of Nutrition 50, 463470.CrossRefGoogle Scholar
Tamminga, S. (1979). Journal of Animal Science 49, 16151630.CrossRefGoogle Scholar
Varvikko, T. & Lindberg, J. E. (1985). British Journal of Nutrition 54, 473481.Google Scholar
Varvikko, T., Lindberg, J. E., Setäläa, J. & Syrjälä-Qvist, L. (1983). Journal of Agricultural Science, Cambridge 101, 603–612.Google Scholar
Weakley, D. C., Stern, M. D. & Satter, L. D. (1983). Journal of Animal Science 56, 493507.Google Scholar
Weller, R. A. (1957). Australian Journal of Biological Sciences 10, 384389.CrossRefGoogle Scholar
Williams, P. P. & Dinusson, W. E. (1973). Journal of Animal Science 36, 151155.Google Scholar