Register      Login
Crop and Pasture Science Crop and Pasture Science Society
Plant sciences, sustainable farming systems and food quality
Shopping Cart: ( empty )
You are here: Home > Journals > CP > AR04111
RESEARCH ARTICLE
Contents Vol 56(8)

In vitro degradability of feed proteins in the rumen: use of non-rumen proteases

M. Aslam Mirza A C and E. L. Miller B
+ Author Affiliations
- Author Affiliations

A Institute of Animal Nutrition and Feed Technology, University of Agriculture, Faisalabad, Pakistan.

B Department of Veterinary Medicine, University of Cambridge, Madingley Road, Cambridge, United Kingdom CB3 OES.

C Corresponding author. Email: mmirza@nsac.ns.ca

Australian Journal of Agricultural Research 56(8) 797-801 https://doi.org/10.1071/AR04111
Submitted: 17 May 2004  Accepted: 14 June 2005   Published: 25 August 2005

Abstract

Various feed proteins were incubated independently with bacterial protease from Streptomyces griseus (SGP), papain (Corica papaya), and ficin (Ficus glabrata) in a simple laboratory assay to predict ruminal protein degradability. The estimates obtained from in vitro assays were compared with those obtained from an in situ analysis using synthetic fibre bags. The rate and extent of degradation in vitro using proteases from non-rumen sources differed among substrates used. A high correlation coefficient (r2 = 0.99) was observed between N-degradability from the in vitro method using SGP and in situ estimates when soybean meal was the substrate. Soybean meal nitrogen (N) was almost completely hydrolysed (0.99) in vitro. The correlation coefficients were low and variable with assays using other enzymes. The correlation coefficient was also high (r2 = 0.77–0.84) with in vitro methods using either SGP, papain, or ficin when incubated with fish meal. The N disappearance from barley in vitro was slow to moderate. The ‘b’ estimate of barley obtained with the in vitro assay was significantly (P < 0.01) lower than that observed in situ. Slower proteolysis observed in barley may possibly be linked to poor accessibility of structural proteins rather than the degradability of N per se. None of the enzymes could rank barley in the same order as the in situ method.

Additional keywords: protein degradation, bacterial protease, papain, ficin.


Acknowledgments

This study was sponsored by the Cambridge Commonwealth Trust in the form of a scholarship provided to the first author. The assistance of Dr Alan Fredeen, Haley Institute of Animal Science and Aquaculture, NSAC, Truro, NS, in reading the manuscript and giving useful suggestions is gratefully acknowledged.


References


AOAC (1990). ‘Official methods of analysis.’ 15th edn . (Association of Official Analytical Chemists: Arlington, VA)

ARC (1980). ‘The nutrient requirements of ruminant livestock.’ (Commonwealth Agricultural Bureaux: Slough, England)

Barret, AJ ,  and  Salvesen, G (1986). ‘Proteinase inhibitors.’ (Elsevier Scientific Publishers BV: Amsterdam, The Netherlands)

Chamberlain DG, Thomas PC (1979) Prospective laboratory methods for estimating the susceptibility of feed proteins to microbial breakdown in the rumen. The Proceedings of the Nutrition Society 38, 138A.
| PubMed |
open url image1

Clark JH, Klusmeyer TH (1989) Dairy production: optimising microbial protein. Feed International Sept., 47–52. open url image1

Coblentz WK, Abdelgadir IEO, Cochran RC, Fritz JO, Fick WH, Olson KC, Turner JE (1999) Degradability of forage proteins by in situ and in vitro enzymatic methods. Journal of Dairy Science 83, 343–354. open url image1

Cottrill BR, Evan PJ (1984) Estimation of protein degradability. Interdepartmental Protein Working Party, ARC Technical Review.

Miller EL (1978) Evaluating the protein contribution of feedstuffs for ruminants. Technical Bulletin, International Association of Fish Meal Manufacturers, Hertfordshire, UK.

Nocek JE (1988) In situ and other methods to estimate ruminal protein and energy digestibility; a review. Journal of Dairy Science 71, 2051–2069. open url image1

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

Pichard G, Van Soest PJ (1977) Protein solubility of ruminant feeds. ‘Proceedings of Cornell Nutrition Conference for Feed Manufacturers’. (Cornell University: Ithaca, NY)


Pion R, Genest C, Bayle G, Thivend P (1983) Assessment of protein degradability in concentrates using an enzymatic method. ‘6th International Symposium on Protein Metabolism and Nutrition’. (INRA Publ. (Les Colloques de I’INRA, No. 16): Clermont-Ferrand, France)


Poos-Floyd M, Klopfenstein T, Britton RA (1985) Evaluation of laboratory techniques for predicting ruminal protein degradation. Journal of Dairy Science 68, 829–839. open url image1

Roe MB, Chase LE, Sniffen CJ (1991) Comparison of in vitro techniques to the in situ technique for estimation of ruminal degradation of protein. Journal of Dairy Science 74, 1632–1640.
| PubMed |
open url image1

Siddons RC, Paradine J (1983) Protein degradation in the rumen of sheep and cattle. Journal of the Science of Food and Agriculture 34, 701–708.
| PubMed |
open url image1

Siddons RC, Paradine J, Gale DL, Evans RT (1985) Estimation of the degradability of dietary protein in the sheep rumen by in vivo and in vitro procedure. Journal of Nutrition 54, 545–561.
| Crossref | GoogleScholarGoogle Scholar | open url image1

Tecator (1981). ‘Determination of Kjeldah nitrogen content with Kjeltec Auto Systems I, II, III and IV. Application note AN30181.’ (Tecator Ltd: Thornbury, Bristol, UK)