Hostname: page-component-84b7d79bbc-dwq4g Total loading time: 0 Render date: 2024-07-26T22:18:07.907Z Has data issue: false hasContentIssue false

Changes in the cell wall components of laboratory silages and the effect of various additives on these changes

Published online by Cambridge University Press:  27 March 2009

I. M. Morrison
Affiliation:
Hannah Research Institute, Ayr KA6 5HL

Summary

A series of laboratory silages were prepared and opened after 2, 20, 60 and 150 days. The silages were made without any additive and with formaldehyde, formic acid, hexanoic acid, benzoic acid or sulphuric acid. The cellulose, hemicellulose, acetyl, alkali-labile phenolic acids and core lignin were determined in all silages as well as the composition of the hemicelluloses. In all the silages, the core lignin remained unchanged while the cellulose content only decreased by up to 5%. Large losses of acetyl residues and alkali-labile phenolic acids were observed in all the silages and losses of 10–20% of the hemicelluloses were found. The losses of hemicellulose were not uniform. The arabinose side chains were preferentially cleaved relative to the xylose residues. It was shown that part of the loss of carbohydrate could have been caused by the acidic conditions in the silage as well as by microbial activity. The silages made using the acidic additives with the highest pKa values lost the greatest proportion of carbohydrate. The implications of these results on rumen activity are discussed.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1979

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

Bethge, P. O. & Lindström, K. (1973). Determination of O-acetyl groups in wood. Svensk Papperstidnung 76, 645649.Google Scholar
Crampton, E. Q. & Maynard, L. A. (1938). The relation of cellulose and lignin content to the nutritive value of animal feeds. Journal of Nutrition 15, 383395.Google Scholar
Crawshaw, R. (1977). An approach to the evaluation of silage additives. A.D.A.S. Quarterly Review 24, 115.Google Scholar
Dewab, W. A., McDonald, P. & Whittenbury, B. (1963). The hydrolysis of grass hemicelluloses during ensilage. Journal of the Science of Food and Agriculture 14, 411417.Google Scholar
Dubois, M., Gilles, K. A., Hamilton, J. K., Rebers, P. A. & Smith, F. (1956). Colorimetric method for determination of sugars and related substances. Analytical Chemistry 28, 350356.CrossRefGoogle Scholar
Gilligan, W. & Reese, E. T. (1954). Evidence for multiple components in microbial cellulases. Canadian Journal of Microbiology 1, 90107.CrossRefGoogle ScholarPubMed
McDonald, P. & Henderson, A. R. (1974). The use of fatty acids as grass silage additives. Journal of the Science of Food and Agriculture 25, 791795.Google Scholar
McDonald, P., Henderson, A. R. & McGregor, A. W. (1968). Chemical changes and losses during the ensilage of wilted grass. Journal of the Science of Food and Agriculture 19, 125132.CrossRefGoogle Scholar
Minson, D. J. (1971). The place of chemistry in pasture evaluation. Proceedings of the Royal Australian Chemical Institute 38, 141145.Google Scholar
Morrison, I. M. (1972a). A semi-micro method for the determination of lignin and its use in predicting the digestibility of forage crops. Journal of the Science of Food and Agriculture 23, 455463.CrossRefGoogle ScholarPubMed
Morrison, I. M. (1972b). Improvements in the acetyl bromide technique to determine lignin and digestibility and its application to legumes. Journal of the Science of Food and Agriculture 23, 14631469.CrossRefGoogle Scholar
Morrison, I. M. (1975a). Determination of the degree of polymerisation of oligo- and polysaccharides by gas-liquid chromatography. Journal of Chromatography 108, 361364.Google Scholar
Morbison, I. M. (1975b). The rate and products of degradation of xylans by rumen hemicellulases. Biochemical Society Transactions 3, 992994.Google Scholar
Ohshima, M. & McDonald, P. (1978). A review of the changes in nitrogenous compounds of herbage during ensilage. Journal of the Science of Food and Agriculture 29, 497505.CrossRefGoogle Scholar
Timell, T. E. (1965). Wood hemicelluloses. II. Advances in Carbohydrate Chemistry 20, 409483.Google Scholar
Watson, S. J. & Nash, M. J. (1960). In The conservation of grass and forage crops, p. 215. Edinburgh and London: Oliver and Boyd.Google Scholar
Wilkins, R. J., Watson, R. F. & Woolfobd, M. K. (1974). The effects of formaldehyde on the silage fermentation. Vaxtodling 29, 197201. Proceedings of the 5th General Meeting of the European Grassland Federation, Uppsala, 1973.Google Scholar
Wise, L. E., Murphy, M. & D'Addiceo, A. A. (1946). Chlorite holocellulose, its fractionation and bearing on summative wood analysis and on studies on the hemicelluloses. Paper Trade Journal 122, 3543.Google Scholar
Woolford, M. K. (1975a). Microbial screening of the straight chain fatty acids (C1—-C12) as potential silage additives. Journal of the Science of Food and Agriculture 26, 219228.CrossRefGoogle Scholar
Woolford, M. K. (1975b). Microbial screening of food preservatives, cold sterilants and specific antimicrobial agents as potential silage additives. Journal of the Science of Food and Agriculture 26, 229237.CrossRefGoogle Scholar