Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-26T18:23:14.006Z Has data issue: false hasContentIssue false
  • English
  • Français

The potential digestibility of leaf and stem fractions of grasses

Published online by Cambridge University Press:  27 March 2009

I. Goto  and
D. J. Minson
I. Goto
Affiliation:
Division of Tropical Crops and Pastures, C.S.I.R.O., Cunningham Laboratory, Mill Road, St Lucia, Queensland, Australia
D. J. Minson
Affiliation:
Division of Tropical Crops and Pastures, C.S.I.R.O., Cunningham Laboratory, Mill Road, St Lucia, Queensland, Australia
Get access Rights & Permissions [Opens in a new window]

Summary

The potential digestibility of leaf and stem fractions of Rhodes grass (Chloris gayana) and Pangola grass (Digitaria decumbens) were determined by incubating in vitro with rumen fluid for 4, 7, 11 and 14 days with reinoculation after 7 days. The mean drymatter solubility (DMS) of four leaf and four stem samples from the two species, increased from 53·6% after 4 days to 63·8% after 14 days with increases of 14·9 and 5·7% for leaf and stem respectively. Prolonged incubation of sheep faeces from these feeds gave similar patterns of DMS as those for the original feed.

To determine the cause of the observed rise in DMS, leaf and stem of Rhodes grass was incubated for 21 days with rumen fluid and Onozuka cellulase. When using cellulose, DMS increased by 7·7% compared with 14·6% when using rumen fluid. The higher DMS with rumen fluid was associated with an increase in the mean disappearance of lignin from 33·6% at 4 days to 52·6% after 21 days. After 14 days there was no further loss of lignin from most samples indicating the existence of a hard resistant lignin core.

It was concluded that when determining potential digestibility forages must be incubated with rumen inoculum for at least 21 days and that shorter incubation times may lead to biased conclusions.

Type
Research Article
Information
The Journal of Agricultural Science , Volume 89 , Issue 1 , August 1977 , pp. 143 - 149
Copyright
Copyright © Cambridge University Press 1977

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

Beferences

Bagby, M. O., Cunningham, R. L. & Maloney, R. L. (1973). Ultra-violet spectral determination of lignin. Journal of the Technical Association of the Pulp and Paper Industry 56, 162–3.Google Scholar
Clark, K. W. (1958). The adaptation of an artificial rumen technique to the estimation of the gross digestible energy of forages. Ph.D. thesis, Purdue University.Google Scholar
Gaillard, B. D. E. & Richards, G. N. (1975). Presence of soluble lignin-carbohydrate complexes in the bovine rumen. Carbohydrate Research 42, 135–45.CrossRefGoogle ScholarPubMed
Jarrett, I. G. (1948). The production of rumen and abomasal fistulae in sheep. Journal of the Council for Scientific and Industrial Research, Australia 21, 311–15.Google Scholar
Laredo, M. A. & Minson, D. J. (1973). The voluntary intake, digestibility and retention time by sheep of leaf and stem fractions of five grasses. Australian Journal of Agricultural Research 24, 875–88.CrossRefGoogle Scholar
Laredo, M. A. (1974). The voluntary intake by sheep given separated leaf and stem fractions of tropical grasses. Ph.D. thesis, University of Queensland.Google Scholar
McAnally, R. A. (1942). Digestion of straw by ruminants. Biochemical Journal 36, 392–9.CrossRefGoogle Scholar
McDougall, E. I. (1948). Studies on ruminant, saliva. 1. The composition and output of sheep's saliva. Biochemical Journal 43, 99–109.CrossRefGoogle ScholarPubMed
McQueen, R. & Van Soest, P. J. (1975). Fungal cellulase and hemi-cellulase prediction of forage digestibility. Journal of Dairy Science 58, 1482–91.CrossRefGoogle Scholar
Minson, D. J. (1976). Relation between digestibility and composition of feed – a review. Miscellaneous papers 12 – Landbouwhogerschool, Wageningen, The Netherlands, pp. 101–14.Google Scholar
Minson, D. J. & McLeod, M. N. (1972). The in vitro technique: its modification for estimating digestibility of large numbers of tropical pasture samples. Technical paper of the Division of Tropical Pastures, Commonwealth Scientific and Industrial Research Organisation, Australia, no. 8, pp. 1–16.Google Scholar
Morrison, I. M. (1972). A semi-micro method for the determination of lignin and its use in predicting the digestibility of forage crops. Journal of Science Food and Agriculture 23, 455–63.CrossRefGoogle ScholarPubMed
Rees, M. C. & Minson, D. J. (1976). Fertilizer calcium as a factor affecting the voluntary intake, digestibility and retention time of pangola grass (Digitaria decumbens) by sheep. British Journal of Nutrition 36, 179–87.CrossRefGoogle ScholarPubMed
Waldo, D. R., Smith, L. W. & Cox, E. L. (1972). Model of cellulose disappearance from the rumen. Journal of Dairy Science 55, 125–9.CrossRefGoogle ScholarPubMed
Wilkins, R. J. (1966). The digestibility of forages and its relation to lignification. Ph.D. thesis, University of New England.Google Scholar
Wilkins, R. J. (1969). The potential digestibility of cellulose in forage and faeces. Journal of Agricultural Science, Cambridge 73, 57–64.CrossRefGoogle Scholar