Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Animal Production Science Animal Production Science Society
Food, fibre and pharmaceuticals from animals
Shopping Cart: ( empty )
You are here: Home > Journals > AN > EA07414
RESEARCH ARTICLE
Contents Vol 48(7)

Ruminal protein degradability of a range of tropical pastures

M. K. Bowen A C D , D. P. Poppi A and S. R. McLennan B
+ Author Affiliations
- Author Affiliations

A Schools of Animal Studies and Veterinary Science, University of Queensland, St Lucia, Qld 4072, Australia.

B Department of Primary Industries and Fisheries, Locked Mail Bag 4, Moorooka, Qld 4105, Australia.

C Present address: Department of Primary Industries and Fisheries, PO Box 6014, CQMC Rockhampton, Qld 4702, Australia.

D Corresponding author. Email: maree.bowen@dpi.qld.gov.au

Australian Journal of Experimental Agriculture 48(7) 806-810 https://doi.org/10.1071/EA07414
Submitted: 18 December 2007  Accepted: 6 March 2008   Published: 20 June 2008

Abstract

The rumen degradability parameters of the diet selected by two to four oesophageal-fistulated Brahman steers grazing a range of tropical pastures were determined by incubation of extrusa in nylon bags suspended in the rumen of rumen-fistulated (RF) Brahman steers. The effective protein degradability (Edg) was determined by measuring the rate of disappearance of neutral detergent insoluble nitrogen (NDIN) less acid detergent insoluble nitrogen (ADIN) in the incubated extrusa. Six to eight RF steers also grazed each of the pastures along with the oesophageal-fistulated steers, to allow determination of key rumen parameters and rumen particulate matter fractional outflow rates (FOR). The seven pastures studied included: native tropical grass (C4) pasture (major species Heteropogon contortus and Bothriochloa bladhii), studied in the early wet (NPEW), the wet/dry transition (NPT) and the dry (NPD) seasons; introduced tropical grass (C4) pasture (Bothriochloa insculpta), studied in the mid wet season (BB); the introduced tropical legumes (C3), Lablab purpureus (LL) and Clitoria ternatea (BP); and the temperate grass (C3) pasture, ryegrass (Lolium multiflorum, RG). Using the measured particle FOR values in calculations, the Edg estimates were very high for both C4 and C3 species: 0.82–0.91 and 0.95–0.98 g/g crude protein (CP), respectively. Substitution of an assumed FOR (kp = 0.02/h) for the measured values for each pasture type did not markedly affect estimates of Edg. However, C4 tropical grasses had much lower effective rumen degradable protein (ERDP) fractions (23–66 g/kg DM) than the C3 pasture species RG and LL (356 and 243 g/kg DM, respectively). This was associated with a lower potential degradability and degradation rate of organic matter (OM) in sacco, lower in vitro organic matter digestibility (IVOMD) and CP concentrations in the extrusa, and lower ammonia-N and branched-chain fatty acid concentrations in rumen fluid for the tropical grasses. As tropical grass pastures senesced, there was a decline in Edg, the ERDP and rumen undegradable protein (UDP) fractions, the potential degradability and degradation rate of OM and the IVOMD. These results provide useful data for estimating protein supply to cattle grazing tropical pastures.


Acknowledgements

This study was mainly funded by the Department of Primary Industries and Fisheries, Queensland (DPI&F), who provided postgraduate support for M. K. Bowen. M. K. Bowen was also in receipt of an Australian Government Postgraduate Research Award. We are grateful to the Health and Nutritional Biochemistry Laboratory of DPI&F for conducting laboratory analyses and to Vivienne Doogan for assistance with statistical analyses. We also thank the staff of Brian Pastures Research Station, Gayndah for providing assistance with field work.


References


ARC (1984) Report of the Protein Group of the Agricultural Research Council Working Party on the Nutrient Requirements of Ruminants. Commonwealth Agricultural Bureaux, Farnham Royal, UK.

Bolleter WT, Bushman CF, Tidwell PW (1961) Spectrophotometric determination of ammonia as indophenol. Analytical Chemistry 33, 592.
| Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

Broderick GA (1994) Quantifying forage protein quality. In ‘National conference on forage quality, evaluation and utilization’. (Eds GC Fahey, M Collins, DR Mertens, LE Moser) pp. 200–228. (University of Nebraska: Lincoln, WL)

CSIRO (2007) ‘Nutrient requirements of domesticated ruminants.’ (Eds M Freer, H Dove, J Nolan ) (CSIRO Publishing: Collingwood, Vic.)

Dixon RM, Chanchai S (2000) Colonization and source of N substrates used by microorganisms digesting forages incubated in synthetic fibre bags in the rumen. Animal Feed Science and Technology 83, 261–272.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Foss Tecator (2002 a) ‘Application sub-note ASN 3805. The determination of neutral detergent fibre using the Fibercap system.’ (Foss Tecator: Hoganas, Sweden)

Foss Tecator (2002 b) ‘Application sub-note ASN 3804. The determination of acid detergent fibre using the Fibercap system.’ (Foss Tecator: Hoganas, Sweden)

Genstat Committee (2000) ‘The guide to Genstat. Part 2: statistics.’ (VSN International Ltd: Oxford, UK)

González J, Faría-Mármol J, Rodríguez CA, Martínez A (2007) Effects of ensiling on ruminal degradability and intestinal digestibility of Italian rye-grass. Animal Feed Science and Technology 136, 38–50.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Hunter RA, Siebert BD (1985) Utilization of low-quality roughage by Bos taurus and Bos indicus cattle. 1. Rumen digestion. The British Journal of Nutrition 53, 637–648.
| Crossref | GoogleScholarGoogle Scholar | CAS | PubMed | open url image1

Klopfenstein TJ, Mass RA, Creighton KW, Patterson HH (2001) Estimating forage protein degradation in the rumen. Journal of Animal Science 79, E208–E217. open url image1

Mass RA, Lardy GP, Grant RJ, Klopfenstein TJ (1999) In situ neutral detergent insoluble nitrogen as a method for measuring forage protein degradability. Journal of Animal Science 77, 1565–1571.
|  CAS | PubMed |
open url image1

McDonald I (1981) Short Note. A revised model for the estimation of protein degradability in the rumen. Journal of Agricultural Science, Cambridge 96, 251–252.
|  CAS |
open url image1

McLeod MN, Minson DJ (1978) The accuracy of the pepsin-cellulase technique for estimating the dry matter digestibility in vivo of grasses and legumes. Animal Feed Science and Technology 3, 277–287.
| Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

McLeod MN, Minson DJ (1980) A note on Onozuka 3S cellulose as a replacement for Onuzuka SS (P1500) cellulose when estimating forage digestibility in vitro. Animal Feed Science and Technology 5, 347–350.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Minson DJ , McLeod MN (1972) The in vitro technique: its modification for estimating digestibility of large numbers of tropical pasture samples. Division of Tropical Pastures, Technical Paper No. 8.

Ørskov ER, McDonald I (1979) The estimation of protein degradability in the rumen from incubation measurements weighted according to rage of passage. Journal of Agricultural Science, Cambridge 92, 499–503. open url image1

Panjaitan TS , McLennan SR , Doogan VJ , Poppi DP (2006) Effect of various rumen degradable protein sources on the rate of fibre digestion of various forages in cattle consuming speargrass hay. Proceedings of the Australian Society of Animal Production 26, Short Communication 83.

SCA (1990) ‘Feeding standards for Australian livestock. Ruminants.’ (CSIRO Publishing: East Melbourne, Vic.)

Sniffen CJ, O’Connor JD, Van Soest PJ, Fox DG, Russell JB (1992) A net carbohydrate and protein system for evaluating cattle diets. II. Carbohydrate and protein availability. Journal of Animal Science 70, 3562–3577.
|  CAS | PubMed |
open url image1

Stobbs TH (1975) Factors limiting the nutritional value of grazed tropical pasture for beef and milk production. Tropical Grasslands 9, 141–150. open url image1

Sweeney RA (1989) Generic combustion method for determination of crude protein in feeds. Journal – Association of Official Analytical Chemists 72, 770–774.
|  CAS | PubMed |
open url image1

Tilley JMA, Terry RA (1963) A two-stage technique for the in vitro digestion of forage crops. Journal of British Grasslands Society 18, 104–111.
|  CAS |
open url image1

Waters CJ, Kitcherside MA, Webster AJF (1992) Problems associated with estimating the digestibility of undegraded dietary nitrogen from acid-detergent insoluble nitrogen. Animal Feed Science and Technology 39, 279–291.
| Crossref | GoogleScholarGoogle Scholar | CAS | open url image1

Webster AJF (1992) The metabolisable protein system for ruminants. In ‘Recent advances in animal nutrition 1992’. (Eds P Garnsworthy, DJA Cole) pp. 93–110. (Butterworth-Heinemann Ltd: London)