Castro-Montoya JM, Makkar HPS, Becker K. 2011. Chemical composition of rumen microbial fraction and fermentation parameters as affected by tannins and saponins using an
in vitro rumen fermentation system. Can J Anim Sci 91:433–448.
Chwalek M, Lalun N, Bobichon H, Ple K, Voutquenne-Nazabadioko L. 2006. Structure-activity relationships of some hederagenin diglycosides: Haemolysis, cytotoxicity and apoptosis induction. Biochim. Biophys Acta 1760:1418–1427.
Cottle DJ, Nolan JV, Wiedemann SG. 2011. Ruminant enteric methane mitigation: a review. Anim Prod Sci 51:491–514.
Desnoyers M, Giger-Reverdin S, Bertin G, Duvaux-Ponter C, Sauvant D. 2009. Meta-analysis of the influence of
Saccharomyces cerevisiae supplementation on ruminal parameters and milk production of ruminants. J Dairy Sci 92:1620–1632.
Eugene M, Archimede H, Sauvant D. 2004. Quantitative meta-analysis on the effects of defaunation of the rumen on growth, intake and digestion in ruminants. Livest Prod Sci 85:81–97.
Feng ZH, Cao YF, Gao YX, Li QF, Li JG. 2012. Effect of gross saponin of
Tribulus terrestris on ruminal fermentation and methane production
in vitro. J Anim Vet Adv 11:2121–2125.
Finlay BJ, Esteban G, Clarke KJ, Williams AG, Embley TM, Hirt RP. 1994. Some rumen ciliates have endosymbiotic methanogens. FEMS Microbiol Lett 117:157–161.
Firkins JL, Allen MS, Oldick BS, St-Pierre NR. 1998. Modeling ruminal digestibility of carbohydrates and microbial protein flow to the duodenum. J Dairy Sci 81:3350–3369.
Francis G, Kerem Z, Makkar HPS, Becker K. 2002. The biological action of saponins in animal systems: A review. Br J Nutr 88:587–605.
Goel G, Makkar HPS, Becker K. 2008. Changes in microbial community structure, methanogenesis and rumen fermentation in response to saponin-rich fractions from different plant materials. J Appl Microbiol 105:770–777.
Guo S, Kenne L, Lundgren LN, Ronnberg B, Sundquist BG. 1998. Triterpenoid saponins from
Quillaja saponaria. Phytochemistry 48:175–180.
Guo YQ, Liu JX, Lu Y, Zhu WY, Denman SE, McSweeney CS. 2008. Effect of tea saponin on methanogenesis, microbial community structure and expression of
mcrA gene, in cultures of rumen micro-organisms. Lett Appl Microbiol 47:421–426.
Gutierrez J, Davis RE. 1959. Bacterial ingestion by the rumen ciliates
Entodinium and
Diplodinium. J Eukaryot Microbiol 6:222–226.
Hegarty RS. 1999. Reducing rumen methane emissions through elimination of rumen protozoa. Aust J Agric Res 50:1321–1328.
Hess HD, Kreuzer M, Diaz TE, Lascano CE, Carulla JE, Soliva CR, Machmueller A. 2003. Saponin rich tropical fruits affect fermentation and methanogenesis in faunated and defaunated rumen fluid. Anim Feed Sci Technol 109:79–94.
Holtshausen L, Chaves AV, Beauchemin KA, McGinn SM, McAllister TA, Odongo NE, Cheeke PR, Benchaar C. 2009. Feeding saponin-containing
Yucca schidigera and
Quillaja saponaria to decrease enteric methane production in dairy cows. J Dairy Sci 92:2809–2821.
Hu WL, Liu JX, Ye JA, Wu YM, Guo YQ. 2005a. Effect of tea saponin on rumen fermentation
in vitro. Anim Feed Sci Technol 120:333–339.
Hu WL, Wu YM, Liu JX, Guo YQ, Ye JA. 2005b. Tea saponins affect
in vitro fermentation and methanogenesis in faunated and defaunated rumen fluid. J. Zhejiang Univ. Sci 6B:787–792.
Hu WL, Liu JX, Wu YM, Guo YQ, Ye JA. 2006. Effects of tea saponins on
in vitro ruminal fermentation and growth performance in growing Boer goat. Arch Anim Nutr 60:89–97.
Jayanegara A, Kreuzer M, Wina E, Leiber F. 2011. Significance of phenolic compounds in tropical forages for the ruminal bypass of polyunsaturated fatty acids and the appearance of biohydrogenation intermediates as examined
in vitro. Anim Prod Sci 51:1127–1136.
Jayanegara A, Leiber F, Kreuzer M. 2012. Meta-analysis of the relationship between dietary tanin level and methane formation in ruminants from
in vivo and
in vitro experiments. J Anim Physiol Anim Nutr 96:365–375.
Kamra DN, Agarwal N, Chaudhary LC. 2006. Inhibition of ruminal methanogenesis by tropical plants containing secondary compounds. Int Congr Ser 1293:156–163.
Khiaosa-ard R, Bryner SF, Scheeder MRL, Wettstein HR, Leiber F, Kreuzer M, Soliva CR. 2009. Evidence for the inhibition of the terminal step of ruminal α-linolenic acid biohydrogenation by condensed tannins. J Dairy Sci 92:177–188.
Koenig KM, Newbold CJ, McIntosh FM, Rode LM. 2000. Effects of protozoa on bacterial nitrogen recycling in the rumen. J Anim Sci 78:2431–2445.
Kurihara Y, Eadie JM, Hobson PN, Mann SO. 1968. Relationship between bacteria and ciliate protozoa in the sheep rumen. J Gen Microbiol 51:267–288.
Lassey KR. 2008. Livestock methane emission and its perspective in the global methane cycle. Aust J Exp Agric 48:114–118.
Li W, Powers W. 2012. Effects of saponin extracts on air emissions from steers. J Anim Sci 90:4001–4013.
Lila ZA, Mohammed N, Kanda S, Kamada T, Itabashi H. 2003. Effect of sarsaponin on ruminal fermentation with particular reference to methane production
in vitro. J Dairy Sci 86:3330–3336.
Makkar HPS, Francis G, Becker K. 2007. Bioactivity of phytochemicals in some lesser-known plants and their effects and potential applications in livestock and aquaculture production systems. Animal 1:1371–1391.
Malik PK, Singhal KK. 2008. Influence of supplementation of wheat straw based total mixed ration with saponins on total gas and methane production in vitro. Indian J Anim Sci 78:987–990.
Mao HL, Wang JK, Zhou YY, Liu JX. 2010. Effects of addition of tea saponins and soybean oil on methane production, fermentation and microbial population in the rumen of growing lambs. Livest Sci 129:56–62.
McAllister TA, Newbold CJ. 2008. Redirecting rumen fermentation to reduce methanogenesis. Aust J Exp Agric 48:7–13.
Monteny GJ, Bannink A, Chadwick D. 2006. Greenhouse gas abatement strategies for animal husbandry. Agric Ecosyst Environ 112:163–170.
Morgavi DP, Forano E, Martin C, Newbold CJ. 2010. Microbial ecosystem and methanogenesis in ruminants. Animal 4:1024–1036.
Moss AR, Jouany JP, Newbold J. 2000. Methane production by ruminants: its contribution to global warming. Ann Zootech 49:231–253.
Narvaez N, Wang Y, McAllister T. 2013. Effects of extracts of
Humulus lupulus(hops) and
Yucca schidigera applied alone or in combination with monensin on rumen fermentation and microbial populations
in vitro. J Sci Food Agric 93:2517–2522.
Newbold CJ, Lassalas B, Jouany JP. 1995. The importance of methanogens associated with ciliate protozoa in ruminal methane production
in vitro. Lett Appl Microbiol 21:230–234.
Oleszek W, Sitek M, Stochmal A, Piacente S, Pizza C, Cheeke P. 2001. Steroidal saponins of
Yucca schidigera Roezl. J Agric Food Chem 49:4392–4396.
Patra AK, Saxena J. 2009. The effect and mode of action of saponins on the microbial populations and fermentation in the rumen and ruminant production. Nutr Res Rev 22:204–219.
Patra AK, Yu Z. 2013. Effective reduction of enteric methane production by a combination of nitrate and saponin without adverse effect on feed degradability, fermentation, or bacterial and archaeal communities of the rumen. Bioresour Technol 148:352–360.
Pen B, Sar C, Mwenya B, Kuwaki K, Morikawa R, Takahashi J. 2006. Effects of
Yucca schidigera and
Quillaja saponaria extracts on
in vitro ruminal fermentation and methane emission. Anim Feed Sci Technol 129:175–186.
Pen B, Takaura K, Yamaguchi S, Asa R, Takahashi J. 2007. Effects of
Yucca schidigera and
Quillaja saponaria with or without β 1–4 galacto-oligosaccharides on ruminal fermentation, methane production and nitrogen utilization in sheep. Anim Feed Sci Technol 138:75–88.
Pen B, Sar C, Mwenya B, Takahashi J. 2008. Effects of
Quillaja saponaria extract alone or in combination with
Yucca schidigera extract on ruminal fermentation and methanogenesis
in vitro. Anim Sci J 79:193–199.
Santoso B, Mwenya B, Sar C, Gamo Y, Kobayashi T, Morikawa R, Kimura K, Mizukoshi H, Takahashi J. 2004. Effects of supplementing galacto-oligosaccharides,
Yucca schidigera or nisin on rumen methanogenesis, nitrogen and energy metabolism in sheep. Livest Prod Sci 91:209–217.
SAS Institute Inc. 2008. SAS/STAT Software version 9.1. SAS Institute Inc; Cary, NC, USA:
Sauvant D, Schmidely P, Daudin JJ, St-Pierre NR. 2008. Meta-analyses of experimental data in animal nutrition. Animal 2:1203–1214.
Sliwinski BJ, Soliva CR, Machmueller A, Kreuzer M. 2002. Efficacy of plant extracts rich in secondary constituents to modify rumen fermentation. Anim Feed Sci Technol 101:101–114.
Staerfl SM, Kreuzer M, Soliva CR. 2010.
In vitro screening of unconventional feeds and various natural supplements for their ruminal methane mitigation potential when included in a maize-silage based diet. J Anim Feed Sci 19:651–664.
St-Pierre NR. 2001. Integrating quantitative findings from multiple studies using mixed model methodology. J Dairy Sci 84:741–755.
Takahashi J. 2011. Some prophylactic options to mitigate methane emission from animal agriculture in Japan. Asian Australas J Anim Sci 24:285–294.
Thorpe A. 2009. Enteric fermentation and ruminant eructation: the role (and control?) of methane in the climate change debate. Clim Change 93:407–431.
Van Nevel CJ, Demeyer DI. 1996. Control of rumen methanogenesis. Environ Monit Assess 42:73–97.
Vincken JP, Heng L, de Groot A, Gruppen H. 2007. Saponins, classification and occurrence in the plant kingdom. Phytochemistry 68:275–297.
Voutquenne L, Lavaud C, Massiot G, Men-Olivier Le. 2002. Structure-activity relationships of haemolytic saponins. Pharm Biol 40:253–262.
Wallace RJ, Arthaud L, Newbold CJ. 1994. Influence of
Yucca schidigera extract on ruminal ammonia concentrations and ruminal microorganisms. Appl Environ Microbiol 60:1762–1767.
Wallace RJ, McEwan NR, McIntosh FM, Teferedegne B, Newbold CJ. 2002. Natural products as manipulators of rumen fermentation. Asian Australas J Anim Sci 15:1458–1468.
Wang Y, McAllister TA, Newbold CJ, Rode LM, Cheeke PR, Cheng KJ. 1998. Effects of
Yucca schidigera extract on fermentation and degradation of steroidal saponins in the rumen simulation technique (RUSITEC). Anim Feed Sci Technol 74:143–153.
Wang Y, McAllister TA, Yanke LJ, Cheeke PR. 2000. Effect of steroidal saponin from
Yucca schidigera extract on ruminal microbes. J Appl Microbiol 88:887–896.
Wang CJ, Wang SP, Zhou H. 2009. Influences of flavomycin, ropadiar, and saponin on nutrient digestibility, rumen fermentation, and methane emission from sheep. Anim Feed Sci Technol 148:157–166.
Wina E, Muetzel S, Becker K. 2005. The impact of saponins or saponin-containing plant materials on ruminant production – A review. J Agric Food Chem 53:8093–8105.
Wina E, Muetzel S, Becker K. 2006. Effects of daily and interval feeding of
Sapindus rarak saponins on protozoa, rumen fermentation parameters and digestibility in sheep. Asian Australas J Anim Sci 19:1580–1587.
Xu M, Rinker M, McLeod KR, Harmon DL. 2010.
Yucca schidigera extract decreases
in vitro methane production in a variety of forages and diets. Anim Feed Sci Technol 159:18–26.
Zhao P, Gao DF, Xu M, Shi ZG, Wang D, Yang CR, Zhang YJ. 2011. Triterpenoid saponins from the genus camellia. Chem Biodivers 8:1931–1942.
Zhou YY, Mao HL, Jiang F, Wang JK, Liu JX, McSweeney CS. 2011. Inhibition of rumen methanogenesis by tea saponins with reference to fermentation pattern and microbial communities in Hu sheep. Anim Feed Sci Technol 166–167:93–100.