Akin, D.E. and Amos, H.E. 1979. Mode of attack on orchard grass leaf blades by rumen protozoa. Applied and Environmental Microbiology. 37:332-338.
Ankrah, P., Loerch, S.C., Kampman, K.A. and Dehority, B.A. 1990. Effects of defaunation on in situ dry matter and nitrogen disappearance in steers and growth of lambs. Journal of Animal Science. 68:3330-3336.
AOAC. 1995. Official methods of analsis. 13th ed. Association of official analytical chemists, Washington, DC.
Baker, A.J. 1973. Effect of lignin on the in vitro digestibility of wood pulp. Journal of Animal Science. 36:768-771.
Chaudhary, L.C., Srivastava, A. and Singh, K.K. 1995. Rumen fermentation pattern and digestion of structural carbohydrates in buffalo (Bubalusbubalis) calves as affected by ciliate protozoa. Animal Feed Science and Technology. 56:111-117.
Coleman, G.S. 1986. The distribution of carboxymethylcellulase between fractions taken from the rumens of sheep containing no protozoa or one of five different protozoal populations. Journal of Agricultural Science.106:121-127.
Dijkstra, J. and Tamminga, S. 1995. Simulation of the effects of diet on the contribution of rumen protozoa to degradation of fiber in the rumen. British Journal of Nutrition. 74:617-634.
Dohme, F., Machmuller, A., Estermann, B.L., Pfister, P., Wasserfallen, A. and Kreuzer, M. 1999. The role of the rumen ciliate protozoa for methane suppression caused by coconut oil. Letters in Applied Microbiology. 29:187-192.
Eugene, M., Archimede, H., Doreau, B.M. and Fonty, F. 2004. Effects of defaunation on microbial activities in the rumen of rams consuming a mixed diet (fresh Digitaria decumbens grass and concentrate). Animal. 53:187-200.
Fawcett, J.K. and Scott, J.E. 1960. A rapid and precise method for the determination of urea. Journal of Clinical Pathology. 13:156-163.
Finlay, B.J., Esteban, G., Clarke, K.J., Williams, A.G., Embley, T.M. and Hirt, R.R. 1994. Some rumen ciliates have endosymbiotic methanogens. FEMS Microbiology Letters. 117:157-162.
Harrison, D.G. and McAllan, A.B. 1980. Factors affecting microbial growth yields in the reticuio-rumen. In: Digestive Physiology and Metabolism in Ruminants (Ed. Y. Ruckebush and P. Thivend). MTP Press, Lancaster, England. pp. 205-226.
Hegarty, R.S. 1999. Reducing rumen methane emissions though elimination of rumen protozoa. Australian Journal of Agricultural Research. 50:1321-1328.
Hook, S.E., Wright, A.G. and McBride, B.W. 2010. Methanogens: Methane producers of the rumen and mitigation strategies. Archaea. doi:10.1155/2010/945785.
Hungate, R.E., Smith, W., Bauchopo, T., Yu, I. and Rabinowitz, J.C. 1970. Formate as an intermediate in the bovine rumen fermentation. Journal of Bacteriology. 102:389-397.
Jin, G.L., Shinekhuu, J., Qin, W.Z., Kim, J.K., Ju, J.K., Suh, S.W. and Song, M.K. 2012. Effect of protein fractionation and buffer solubility of forage sources on in vitro fermentation characteristics, degradability and gas production. Journal of the Korean Society of Grassland and Forage Science. 32:59-74.
Johnson, D.E., Johnson, K.A., Ward, G.M. and Branine, M.E. 2000. Ruminants and other animals. In: Atmospheric Methane (Ed. M.A.K. Khalil). Springer-Verlag, Berlin, Germany. pp. 112-133.
Johnson, K.A. and Johnson, D.E. 1995. Methane emissions from cattle. Journal of Animal Science. 73:2483-2492.
Kiran, D. and Mutsvangwa, T. 2010. Effects of partial ruminal defaunation on urea-nitrogen recycling, nitrogen metabolism, and microbial nitrogen supply in growing lambs fed low or high dietary crude protein concentrations. Journal of Animal Science. 88:1034-1047.
Kreuzer, M., Kirchgessner, M. and Muller, H.L. 1986. Effect of defaunation on the loss of energy in wethers fed different quantities of cellulose and normal or steam flaked maize starch. Animal Feed Science and Technology. 16:233-241.
Li, X.Z., Long, R.J., Yan, C.G., Choi, S.H., Jin, G.L. and Song, M.K. 2010. Rumen microbial responses in fermentation characteristics and production of CLA and methane to linoleic acid in associated with malate or fumarate. Animal Feed Science and Technology. 155:132-139.
Li, X.Z., Yan, C.G., Choi, S.H., Long, R.J., Jin, G.L. and Song, M.K. 2009. Effects of addition level and chemical type of propionate precursors in dicarboxylic acid pathway on fermentation characteristics and methane production by rumen microbes in vitro. Asian-Australasian Journal of Animal Science. 22:82-89.
Mathieu, F., Jouany, J.P., Senaud, J., Bohatier, J., Bertin, G. and Mercier, M. 1996. The effect of Saccharomyces cerevisiae and Aspergillus oryzae on fermentations in the rumen of faunated and defaunated sheep; protozoal and probiotic interactions. Reproduction Nutrition Development. 36:271-287.
McDougall, E.I. 1948. Studies on ruminant saliva. I. The composition and output of sheep's saliva. Biochemical Journal. 43:99-109.
Morgavi, D.P., Forano, E., Martin, C. and Newbold, C.J. 2010. Microbial ecosystem and methanogenesis in ruminants. Animal. 4:1024-1036.
Morgavi, D.P., Jouany, J.P. and Martin, C. 2008. Changes in methane emission and rumen fermentation parameters induced by refaunation in sheep. Australian Journal of Experimental Agriculture. 48:69-72.
Moss, A.R., Jouany, J.P. and Newbold, J. 2000. Methane production by ruminants: Its contribution to global warming. Annual Zootechnology. 49:231-253.
Oh, J.H., Weir, W.C. and Longhurst, W.M. 1971. Feed value for sheep of cornstalks, rice straw and barley straw as compared with alfalfa. Journal of Animal Science. 32:343-347.
Orskov, E.R. and McDonald, I. 1979. The estimation of protein degradability in the rumen from incubation measurements weighted according to rate of passage. Journal of Agricultural Science. 92:499-506.
SAS. 2002. SAS User's guide: Statistical analysis system institute, SAS Inc., Cary, NC, USA.
Sharp, R., Ziemer, C.J., Stern, M.D. and Stahl, D.A. 1998. Taxon-specific associations between protozoal and methanogen populations in the rumen and a model rumen system. FEMS Microbiology Ecology. 26:71-78.
Tandon, M., Pandy, H. and Singh, V. 2005. Methane production, global warming and ozone layer depletion: A challenge for eco-friendly livestock farming. International Conference on Environment and Development: Challenges and Opportunities. New Delhi. pp. 36.
Ushida, K. and Jouany, J.P. 1990. Effect of defaunation on fibre digestion in sheep given two isonitrogenous diets. Animal Feed Science and Technology. 29:153-158.
Van Soest, P.J., Robertson, J.B. and Lewis, B.A. 1991. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. Journal of Dairy Science. 74:3583-3597.
Williams, B.A. 2000. Cumulative gas-production techniques for forage evaluation. In: Forage Evaluation in Ruminant Nutrition (Ed. D. I. Givens, E. Owen, R. F. E. Axford and H. M. Omed) CAB Int., Oxfordshire, UK. pp. 189-213.
Wina, E., Muetzel, S. and Becker, K. 2006. The dynamics of major fibrolytic microbes and enzyme activity in the rumen in response to short-and long-term feeding of sapindusrarak saponins. Journal of Applied Microbiology. 100:114-122.
Wolin, M., Miller, T. and Stewart, C. 1997. Microbe-microbe interactions. In: The rumen microbial ecosystem(Ed. P. Hobson and C. Stewart). Chapman & Hall, London. pp. 467-491.