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Associative effects between forages on feed intake and digestion in ruminants

Published online by Cambridge University Press:  01 July 2009

V. Niderkorn  and
R. Baumont
V. Niderkorn*
Affiliation:
INRA, UR1213 Herbivores, F-63122 Saint Genès-Champanelle, France
R. Baumont
Affiliation:
INRA, UR1213 Herbivores, F-63122 Saint Genès-Champanelle, France
*
E-mail: vniderk@clermont.inra.fr
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Abstract

The feeding value of forage mixtures from permanent and temporary multi-species grasslands cannot always be precisely defined. Indeed, the digestibility and feed intake of a combination of forages can differ from the balanced median values calculated from forages considered separately. In order to present an overview of the associative effects between forages on digestion and intake, a literature study was carried out. The associative effects can be studied in a complementary way in vitro to test digestive interactions of a large number of mixtures and to carry out explanatory experiments, and in vivo to investigate intake and digestion at the whole animal scale. We identified three main situations in which interactions between forages can lead to associative effects on intake and digestion: (i) increased intake that can be observed with grass and legume association can be explained by fast digestion of the soluble fraction of legumes, and a higher rate of particle breakdown and passage through the rumen, (ii) increased digestion when a poor forage is supplemented by a high nitrogen content plant can be explained by stimulation of the microbial activity and (iii) modification of digestive processes in the rumen, including proteolysis and methane production when certain bioactive secondary metabolites such as tannins, saponins or polyphenol oxidase are present. According to the type and concentration of these compounds in the diet, the effects can be favourable or unfavourable on intake and digestive parameters. Reported associative effects between forages show a large variability among studies. This reflects the complexity and multiplicity of nutritional situations affecting intake and the rumen function in a given animal. In order to provide more reliable information, further accumulation of data combining in vitro and in vivo studies is required. A better understanding of the associative effects between forages could help to optimise feed use efficiency, resulting in greater productivity, a reduction of the environmental impact of animal emissions and more sustainable animal production.

Keywords

ruminantsforagesassociative effectsfeed intakedigestion

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animal , Volume 3 , Issue 7 , July 2009 , pp. 951 - 960
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Copyright © The Animal Consortium 2009

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References

Abreu, A, Carulla, JE, Lascano, CE, Diaz, TE, Kreuzer, M, Hess, HD 2004. Effects of Sapindus saponaria fruits on ruminal fermentation and duodenal nitrogen flow of sheep fed a tropical grass diet with and without legume. Journal of Animal Science 82, 1392–1400.Google Scholar
Albrecht, K, Muck, R 1991. Proteolysis in ensiled forage legumes that vary in tannin concentration. Crop Science 31, 464–469.CrossRefGoogle Scholar
Atwell, D, Merchen, N, Jaster, E, Fahey, G, Berger, L, Titgemeyer, E, Bourquin, L 1991. Intake, digestibility, and in situ digestion kinetics of treated wheat straw and alfalfa mixtures fed to Holstein heifers. Journal of Dairy Science 74, 3524–3534.CrossRefGoogle Scholar
Aufrere, J, Dudilieu, M, Poncet, C, Baumont, R, Dumont, B 2007. Effect of condensed tannins in sainfoin on in vitro protein solubility of lucerne as affected by the proportion of sainfoin in the mixture and the preserving conditions. Options Méditerranéennes. Serie A, 63–66.Google Scholar
Barry, TN, McNabb, WC 1999. The implications of condensed tannins on the nutritive value of temperate forages fed to ruminants. The British Journal of Nutrition 81, 263–272.Google Scholar
Barry, TN, Reid, CSW 1984. Nutritional effects attributable to condensed tannins, cyanogenic glucosides and oestrogenic compounds in temperate forages fed to ruminants. In Forage legumes for energy-efficient animal production (ed. RF Barnes), pp. 251–258. USDA, Agricultural Research Service, Washington, DC.Google Scholar
Barry, TN, North, P, Zealand, N 1997. Potential roles of tree fodders in ruminant nutrition. In Tree foliage in ruminant nutrition, FAO animal production and health paper 139 (ed. RA Leng), Armidale, New South Wales, Australia. http://www.fao.org/docrep/003/w7448e/W7448E04.htm#ch4Google Scholar
Baumont, R, Pomies, D 2004. Feed preferences and voluntary intake of dairy heifers fed grass silage and hays offered singly or as a matter of choice. In Land use systems in grassland dominated regions (ed. A Luscher, B Jeangros, W Kessler, O Huguenin, M Lobsiger, N Millar and D Suter), pp. 1089–1091. Vdf Hochschulverlag AG an der ETH Zurich, Zurich, Switzerland.Google Scholar
Berge, P, Dulphy, JP 1985. Interactions between forages and concentrates in sheep. 1. Variation of substitution rate. Annales de Zootechnie 34, 313–334.Google Scholar
Bhatti, SA, Bowman, JGP, Firkins, JL, Grove, AV, Hunt, CW 2008. Effect of intake level and alfalfa substitution for grass hay on ruminal kinetics of fiber digestion and particle passage in beef cattle. Journal of Animal Science 86, 134–145.CrossRefGoogle ScholarPubMed
Blummel, M, Makkar, HPS, Becker, K 1997. In vitro gas production – a technique revisited. Journal of Animal Physiology and Animal Nutrition 77, 24–34.CrossRefGoogle Scholar
Bobadilla, A, Ramirez Aviles, L, Sandoval Castro, C 2002. Associative effects of tree foliage mixtures as supplements for dual purpose lactating cows. Tropical and Subtropical Agroecosystems 1, 36.Google Scholar
Bowman, JGP, Asplund, JM 1988a. Evaluation of mixed lucerne and caucasian bluestem hay diets fed to sheep. Animal Feed Science and Technology 20, 19–31.CrossRefGoogle Scholar
Bowman, JGP, Asplund, JM 1988b. Nitrogen utilization, ruminal fermentation and abomasal nitrogen flow in sheep fed caucasian bluestem hay supplemented with lucerne or urea. Animal Feed Science and Technology 20, 33–44.CrossRefGoogle Scholar
Brandt, RT, Klopfenstein, TJ 1986. Evaluation of alfalfa–corn cob associative action. I. Comparative tests of alfalfa hay as a source of ruminal degradable protein. Journal of Animal Science 63, 902–910.CrossRefGoogle Scholar
Brown, WF, Pitman, WD 1991. Concentration and degradation of nitrogen and fibre fractions in selected tropical grasses and legumes. Tropical Grasslands 25, 305–312.Google Scholar
Brown, WF, Lai, ZQ, Pitman, WD 1991. In vitro fibre digestion: associative effects in tropical grass–legume mixtures. Tropical Grasslands 25, 297–304.Google Scholar
Butterworth, MH, Mosi, A 1986. The intake and digestibility by sheep of oat straw and maize stover offered with different levels of noug (Guizotia abyssinica) meal. Animal Feed Science and Technology 16, 99–107.CrossRefGoogle Scholar
Castle, M, Reid, D, Watson, J 1983. Silage and milk production: studies with diets containing white clover silage. Grass and Forage Science 38, 193–200.CrossRefGoogle Scholar
Champion, RA, Orr, RJ, Penning, PD, Rutter, SM 2004. The effect of the spatial scale of heterogeneity of two herbage species on the grazing behaviour of lactating sheep. Applied Animal Behaviour Science 88, 61–76.CrossRefGoogle Scholar
Church, DC, Santos, A 1981. Effect of graded levels of soybean meal and of a nonprotein nitrogen-molasses supplement on consumption and digestibility of wheat straw. Journal of Animal Science 53, 1609–1615.Google Scholar
Clarke, RTJ, Reid, CSW 1974. Foamy bloat of cattle. A review. Journal of Dairy Science 57, 753–785.Google Scholar
Collins, W, Cox, R 1985. Oestrogenic activity in forage legumes. In Forage legumes for energy-efficient animal production (ed. RF Barnes), pp. 268–276. USDA, Agricultural Research Service, Washington, DC.Google Scholar
Cone, JW, van Gelder, AH, Visscher, GJW, Oudshoorn, L 1996. Influence of rumen fluid and substrate concentration on fermentation kinetics measured with a fully automated time related gas production apparatus. Animal Feed Science and Technology 61, 113–128.Google Scholar
Cortes, C, Damasceno, JC, Jamot, J, Prache, S 2006. Ewes increase their intake when offered a choice of herbage species at pasture. Animal Science 82, 183–191.CrossRefGoogle Scholar
Davies, ZS, Mason, D, Brooks, AE, Griffith, GW, Merry, RJ, Theodorou, MK 2000. An automated system for measuring gas production from forages inoculated with rumen fluid and its use in determining the effect of enzymes on grass silage. Animal Feed Science and Technology 83, 205–221.Google Scholar
Davies, D, Leemans, D, Merry, R 2002. Ensiling either high or low sugar containing perennial ryegrasses with or without red clover. In Proceedings of the 19th general meeting of the European Grassland Federation on Multi-function grasslands: quality forages, animal products and landscapes (ed. JL Durand, JC Emile, C Huygue and G lemaire), pp. 194–195. La Rochelle, France.Google Scholar
Dewhurst, RJ, Evans, RT, Scollan, ND, Moorby, JM, Merry, RJ, Wilkins, RJ 2003. Comparison of grass and legume silages for milk production. 2. In vivo and in sacco evaluations of rumen function. Journal of Dairy Science 86, 2612–2621.Google Scholar
Diaz, A, Avendano, M, Escobar, A 1993. Evaluation of Sapindus saponaria as a defaunating agent and its effects on different ruminal digestion parameters. Livestock Research for Rural Development 5, 1–6.Google Scholar
Dijkstra, J, Kebreab, E, Bannink, A, France, J, Lopez, S 2005. Application of the gas production technique to feed evaluation systems for ruminants. Animal Feed Science and Technology 123–124, 561–578.Google Scholar
Doran, MP, Laca, EA, Sainz, RD 2007. Total tract and rumen digestibility of mulberry foliage (Morus alba), alfalfa hay and oat hay in sheep. Animal Feed Science and Technology 138, 239–253.CrossRefGoogle Scholar
Doyle, PT, Francis, SA, Stockdale, CR 2005. Associative effects between feeds when concentrate supplements are fed to grazing dairy cows: a review of likely impacts on metabolisable energy supply. Australian Journal of Agricultural Research 56, 1315–1329.Google Scholar
Duncan, AJ, Ginane, C, Gordon, IJ, Orskov, ER 2003. Why do herbivores select mixed diets. In Matching herbivore nutrition to ecosystems biodiversity (ed. L t’Mannetje, C Ramirez-Aviles, CA Sandoval-Castro and JC Ku-Vera), pp. 195–209. Universidad Autonoma de Yucatan, Merida, Mexico.Google Scholar
Edwards, JE, Huws, SA, Kim, EJ, Lee, MRF, Kingston-Smith, AH, Scollan, ND 2008. Advances in microbial ecosystem concepts and their consequences for ruminant agriculture. Animal 2, 653–660.CrossRefGoogle ScholarPubMed
Forbes, JM, Provenza, FD 2000. Integration of learning and metabolic signals into a theory of dietary choice and food intake. In Ruminant physiology: digestion, metabolism, growth and reproduction (ed. P Cronje), pp. 3–19. CABI Publishing, Wallingford, UK.CrossRefGoogle Scholar
Franci, O, Acciaioli, A 1998. Mathematical models for the innovative interpretation of the associative effect. Options Méditerranéennes 17, 73–78.Google Scholar
Franci, O, Antongiovanni, M, Acciaioli, A, Bruni, R, Martini, A 1997. Response surface analyses of the associative effects of lucerne hay, wheat straw and maize gluten feed on growing lambs. Animal Feed Science and Technology 67, 279–290.Google Scholar
Francis, G, Kerem, Z, Makkar, HPS, Becker, K 2002. The biological action of saponins in animal systems: a review. British Journal of Nutrition 88, 587–605.CrossRefGoogle ScholarPubMed
Getachew, G, Makkar, HPS, Becker, K 2000. Effect of polyethylene glycol on in vitro degradability of nitrogen and microbial protein synthesis from tannin-rich browse and herbaceous legumes. British Journal of Nutrition 84, 73–83.Google Scholar
Getachew, G, DePeters, EJ, Robinson, PH, Fadel, JG 2005. Use of an in vitro rumen gas production technique to evaluate microbial fermentation of ruminant feeds and its impact on fermentation products. Animal Feed Science and Technology 123–124, 547–559.CrossRefGoogle Scholar
Ginane, C, Baumont, R, Lassalas, J, Petit, M 2002. Feeding behaviour and intake of heifers fed on hays of various quality, offered alone or in a choice situation. Animal Research 51, 177–188.CrossRefGoogle Scholar
Githiori, JB, Athanasiadou, S, Thamsborg, SM 2006. Use of plants in novel approaches for control of gastrointestinal helminths in livestock with emphasis on small ruminants. Veterinary Parasitology 139, 308–320.CrossRefGoogle ScholarPubMed
Glenn, B 1989. Ruminal fermentation of neutral detergent fibre and nitrogen in legume, grass and mixtures by growing steers. Journal of Animal Science (suppl. 2), 11.Google Scholar
Haddad, SG 2000. Associative effects of supplementing barley straw diets with alfalfa hay on rumen environment and nutrient intake and digestibility for ewes. Animal Feed Science and Technology 87, 163–171.Google Scholar
Harris, SL, Auldist, MJ, Clark, DA, Jansen, EBL 1998. Effects of white clover content in the diet on herbage intake, milk production and milk composition of New Zealand dairy cows housed indoors. The Journal of Dairy Research 65, 389–400.CrossRefGoogle ScholarPubMed
Hart, KJ, Yanez-Ruiz, DR, Duval, SM, McEwan, NR, Newbold, CJ 2008. Plant extracts to manipulate rumen fermentation. Animal Feed Science and Technology 147, 8–35.Google Scholar
Hector, A, Bagchi, R 2007. Biodiversity and ecosystem multifunctionality. Nature 448, 188–190.CrossRefGoogle ScholarPubMed
Hess, HD, Kreuzer, M, Diaz, TE, Lascano, CE, Carulla, JE, Soliva, CR, Machmuller, A 2003. Saponin rich tropical fruits affect fermentation and methanogenesis in faunated and defaunated rumen fluid. Animal Feed Science and Technology 109, 79–94.Google Scholar
Hristov, AN, McAllister, TA, Van Herk, FH, Cheng, KJ, Newbold, CJ, Cheeke, PR 1999. Effect of Yucca schidigera on ruminal fermentation and nutrient digestion in heifers. Journal of Animal Science 77, 2554–2563.CrossRefGoogle ScholarPubMed
Huhtanen, P 1991. Associative effects of feeds in ruminants. Norwegian Journal of Agricultural Sciences (suppl. 5), 37–57.Google Scholar
Hunt, CW, Paterson, JA, Williams, JE 1985. Intake and digestibility of alfalfa–tall fescue combination diets fed to lambs. Journal of Animal Science 60, 301–306.Google Scholar
Hunt, CW, Klopfenstein, TJ, Britton, RA 1988. Effect of alfalfa addition to wheat straw diets on intake and digestion in beef cattle. Nutrition Reports International 38, 1249–1257.Google Scholar
Huyghe, C 2005. Effects of the new milk policies on future trends of forage research. Fourrages 181, 163–177.Google Scholar
Ivan, M, Koenig, KM, Teferedegne, B, Newbold, CJ, Entz, T, Rode, LM, Ibrahim, M 2004. Effects of the dietary Enterolobium cyclocarpum foliage on the population dynamics of rumen ciliate protozoa in sheep. Small Ruminant Research 52, 81–91.Google Scholar
Jones, AL, Goetsch, AL 1987. Effects of dietary forage proportion on digestive function in maintenance-fed beef cows. 1. Fescue and clover hays. Archives of Animal Nutrition 37, 685–699.Google ScholarPubMed
Jones, A, Goetsch, A, Stokes, S, Colberg, M 1987a. Effects of dietary forage proportion on digestive function in maintenance-fed beef cows. 3. Bermudagrass and clover hays. Archives of Animal Nutrition 37, 1009–1020.Google ScholarPubMed
Jones, AL, Goetsch, AL, Stokes, SR 1987b. Effects of dietary forage proportion on digestive function in maintenance-fed beef cows. Fescue and bermudagrass hays. Archives of Animal Nutrition 37, 701–711.Google ScholarPubMed
Kamra, DN, Agarwal, N, Chaudhary, LC 2006. Inhibition of ruminal methanogenesis by tropical plants containing secondary compounds. International Congress Series 1293, 156–163.Google Scholar
Kroll, J, Rawel, HM 2001. Reactions of plant phenols with myoglobin: influence of chemical structure of the phenolic compounds. Journal of Food Science 66, 48–58.Google Scholar
Kumar, R, Singh, M 1984. Tannins: their adverse role in ruminant nutrition. Journal of Agricultural and Food Chemistry 32, 447–453.CrossRefGoogle Scholar
Lagasse, MP, Goetsch, AL, Landis, KM, Forster, LA 1990. Effects of supplemental alfalfa hay on feed intake and digestion by Holstein steers consuming high-quality bermudagrass or orchardgrass hay. Journal of Animal Science 68, 2839–2847.CrossRefGoogle ScholarPubMed
Lee, MRF, Winters, AL, Scollan, ND, Dewhurst, RJ, Theodorou, MK, Minchin, FR 2004. Plant-mediated lipolysis and proteolysis in red clover with different polyphenol oxidase activities. Journal of the Science of Food and Agriculture 84, 1639–1645.Google Scholar
Lee, MRF, Parfitt, LJ, Scollan, ND, Minchin, FR 2007. Lipolysis in red clover with different polyphenol oxidase activities in the presence and absence of rumen fluid. Journal of the Science of Food and Agriculture 87, 1308–1314.Google Scholar
Li, YG, Tanner, G, Larkin, P 1996. The DMACA-HCl protocol and the threshold proanthocyanidin content for bloat safety in forage legumes. Journal of the Science of Food and Agriculture 70, 89–101.3.0.CO;2-N>CrossRefGoogle Scholar
Liu, JX, Susenbeth, A, Sudekum, KH 2002. In vitro gas production measurements to evaluate interactions between untreated and chemically treated rice straws, grass hay, and mulberry leaves. Journal of Animal Science 80, 517–524.CrossRefGoogle ScholarPubMed
Lopez, S, Dhanoa, MS, Dijkstra, J, Bannink, A, Kebreab, E, France, J 2007. Some methodological and analytical considerations regarding application of the gas production technique. Animal Feed Science and Technology 135, 139–156.Google Scholar
Makkar, HPS 2005. In vitro gas methods for evaluation of feeds containing phytochemicals. Animal Feed Science and Technology 123, 291–302.Google Scholar
Makkar, HPS, Becker, K 1997. Degradation of quillaja saponins by mixed culture of rumen microbes. Letters in Applied Microbiology 25, 243–245.CrossRefGoogle ScholarPubMed
Makkar, HPS, Blummel, M, Becker, K 1995. Formation of complexes between polyvinyl pyrrolidones or polyethylene glycols and tannins, and their implication in gas production and true digestibility in in vitro techniques. The British Journal of Nutrition 73, 897–913.CrossRefGoogle ScholarPubMed
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.CrossRefGoogle ScholarPubMed
Martin, C, Morgavi, D, Doreau, M, Jouany, J 2006. How can the production of methane by ruminants be reduced? Fourrages, 283–300.Google Scholar
Martin, C, Morgavi, DP, Doreau, M 2009. Methane mitigation in ruminants: from the microbes to the farm scale. Animal, in press.Google Scholar
Martinez, TF, Moyano, FJ, Diaz, M, Alarcon, FJ, Barroso, FG 2004. Ruminal degradation of tannin-treated legume meals. Journal of the Science of Food and Agriculture 84, 1979–1987.Google Scholar
Mawuenyegah, PO, Shem, MN, Warly, L, Fujihara, T 1997. Effect of supplementary feeding with protein and energy on digestion and rumination behaviour of sheep consuming straw diets. The Journal of Agricultural Science 129, 479–484.CrossRefGoogle Scholar
McMahon, LR, McAllister, TA, Berg, BP, Majak, W, Acharya, SN, Popp, JD, Coulman, BE, Wang, Y, Cheng, KJ 2000. A review of the effects of forage condensed tannins on ruminal fermentation and bloat in grazing cattle. Canadian Journal of Plant Science 80, 469–485.Google Scholar
McSweeney, CS, Palmer, B, Bunch, R, Krause, DO 2001a. Effect of the tropical forage calliandra on microbial protein synthesis and ecology in the rumen. Journal of Applied Microbiology 90, 78–88.Google Scholar
McSweeney, CS, Palmer, B, McNeill, DM, Krause, DO 2001b. Microbial interactions with tannins: nutritional consequences for ruminants. Animal Feed Science and Technology 91, 83–93.Google Scholar
Melaku, S, Peters, KJ, Tegegne, A 2003. In vitro and in situ evaluation of selected multipurpose trees, wheat bran and Lablab purpureus as potential feed supplements to tef (Eragrostis tef) straw. Animal Feed Science and Technology 108, 159–179.Google Scholar
Menke, KH, Raab, L, Salewski, A, Steingass, H, Fritz, D, Schneider, W 1979. The estimation of the digestibility and metabolizable energy content of ruminant feedstuffs from the gas production when they incubated with rumen liquor in vitro. The Journal of Agricultural Science 92, 217–222.Google Scholar
Merry, RJ, Lee, MRF, Davies, DR, Dewhurst, RJ, Moorby, JM, Scollan, ND, Theodorou, MK 2006. Effects of high-sugar ryegrass silage and mixtures with red clover silage on ruminant digestion. 1. In vitro and in vivo studies of nitrogen utilization. Journal of Animal Science 84, 3049–3060.Google Scholar
Min, BR, Hart, SP 2003. Tannins for suppression of internal parasites. Journal of Animal Science 81, 102–109.Google Scholar
Min, BR, McNabb, WC, Barry, TN, Peters, JS 2000. Solubilization and degradation of ribulose-1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39; Rubisco) protein from white clover (Trifolium repens) and Lotus corniculatus by rumen microorganisms and the effect of condensed tannins on these processes. The Journal of Agricultural Science 134, 305–317.Google Scholar
Min, BR, Attwood, GT, McNabb, WC, Molan, AL, Barry, TN 2005. The effect of condensed tannins from Lotus corniculatus on the proteolytic activities and growth of rumen bacteria. Animal Feed Science and Technology 121, 45–58.CrossRefGoogle Scholar
Minson, DJ, Milford, R 1967. The voluntary intake and digestibility of diets containing different proportions of legume and mature pangola grass (Digitaria decumbens). Australian Journal of Experimental Agriculture and Animal Husbandry 7, 546–551.Google Scholar
Moseley, G, Jones, J 1979. Some factors associated with the difference in nutritive value of artificially dried red clover and perennial ryegrass for sheep. British Journal of Nutrition 42, 139–147.Google Scholar
Moseley, G, Jones, JR 1984. The physical digestion of perennial ryegrass (Lolium perenne) and white clover (Trifolium repens) in the foregut of sheep. British Journal of Nutrition 52, 381–390.CrossRefGoogle ScholarPubMed
Moss, AR, Givens, DI, Phipps, RH 1992. Digestibility and energy value of combinations of forage mixtures. Animal Feed Science and Technology 39, 151–172.CrossRefGoogle Scholar
Mould, FL, Orskov, ER, Mann, SO 1983. Associative effects of mixed feeds. I. Effects of type and level of supplementation and the influence of the rumen fluid pH on cellulolysis in vivo and dry matter digestion of various roughages. Animal Feed Science and Technology 10, 15–30.CrossRefGoogle Scholar
Ndlovu, L, Buchanan-Smith, J 1985. Utilization of poor quality roughages by sheep: effects of alfalfa supplementation on ruminal parameters, fiber digestion and rate of passage from the rumen. Canadian Journal of Animal Science 65, 693–703.CrossRefGoogle Scholar
Newbold, CJ, ElHassan, SM, Wang, J, Ortega, ME, Wallace, RJ 1997. Influence of foliage from African multipurpose trees on activity of rumen protozoa and bacteria. British Journal of Nutrition 78, 237–249.Google Scholar
Norton, BW 1994. The Nutritive value of tree legumes. In Forage tree legumes in tropical agriculture (ed. RC Gutteridge and HM Shelton), pp. 177–191. CAB International, Oxon, GB.Google Scholar
Ozturk, D, Kizilsimsek, M, Kamalak, A, Canbolat, O, Ozkan, CO 2006. Effects of ensiling alfalfa with whole-crop maize on the chemical composition and nutritive value of silage mixtures. Asian-Australasian Journal of Animal Sciences 19, 526–532.CrossRefGoogle Scholar
Paterson, JA, Klopfenstein, TJ, Britton, RA 1982. Digestibility of sodium hydroxide treated crop residues when fed with alfalfa hay. Journal of Animal Science 54, 1056–1066.Google Scholar
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. Animal Feed Science and Technology 129, 175–186.Google Scholar
Phillips, CJC, James, NL 1998. The effects of including white clover in perennial ryegrass swards and the height of mixed swards on the milk production, sward selection and ingestive behaviour of dairy cows. Animal Science 67, 195–202.Google Scholar
Reid, RL, Templeton, WCJ, Ranney, TS, Thayne, WV 1987. Digestibility, intake and mineral utilization of combinations of grasses and legumes by lambs. Journal of Animal Science 64, 1725–1734.CrossRefGoogle ScholarPubMed
Ribeiro Filho, HMN, Delagarde, R, Peyraud, JL 2003. Inclusion of white clover in strip-grazed perennial ryegrass swards: herbage intake and milk yield of dairy cows at different ages of sward regrowth. Animal Science 77, 499–510.Google Scholar
Rochfort, S, Parker, AJ, Dunshea, FR 2008. Plant bioactives for ruminant health and productivity. Phytochemistry 69, 299–322.CrossRefGoogle ScholarPubMed
Rosales, MM 1996. In vitro assessment of the nutritive value of mixtures of leaves from tropical fodder trees. PhD, University of Oxford, UK.Google Scholar
Rosales, M, Gill, M, Wood, CD, Speedy, AW 1998. Associative effects in vitro of mixtures of tropical fodder trees. In In vitro techniques for measuring nutrient supply to ruminants (ed. ER Deaville, E Owen, AT Adesogen, C Rymer, JA Huntington and TLJ Lawrence), pp. 175–177. BSAS, Edinburgh, UK. BSAS Occ. Publ. No. 22.Google Scholar
Sandoval-Castro, CA, Capetillo-Leal, C, Cetina-Gongora, R, Ramirez-Aviles, L 2002. A mixture simplex design to study associative effects with an in vitro gas production technique. Animal Feed Science and Technology 101, 191–200.CrossRefGoogle Scholar
Selje, N, Hoffmann, EM, Muetzel, S, Ningrat, R, Wallace, RJ, Becker, K 2007. Results of a screening programme to identify plants or plant extracts that inhibit ruminal protein degradation. British Journal of Nutrition 98, 45–53.Google Scholar
Silva, AT, Orskov, ER 1988. The effect of five different supplements on the degradation of straw in sheep given untreated barley straw. Animal Feed Science and Technology 19, 289–298.Google Scholar
Soder, KJ, Sanderson, MA, Stack, JL, Muller, LD 2006. Intake and performance of lactating cows grazing diverse forage mixtures. Journal of Dairy Science 89, 2158–2167.CrossRefGoogle ScholarPubMed
Soliva, CR, Zeleke, AB, Clement, C, Hess, HD, Fievez, V, Kreuzer, M 2008. In vitro screening of various tropical foliages, seeds, fruits and medicinal plants for low methane and high ammonia generating potentials in the rumen. Animal Feed Science and Technology 147, 53–71.Google Scholar
Tanner, GJ, Moate, PJ, Davis, LH, Laby, RH, Li, YG, Larkin, PJ 1995. Proanthocyanidins (condensed tannin) destabilize plant protein foams in a dose-dependent manner. Australian Journal of Agricultural Research 46, 1101–1109.Google Scholar
Tavendale, MH, Meagher, LP, Pacheco, D, Walker, N, Attwood, GT, Sivakumaran, S 2005. Methane production from in vitro rumen incubations with Lotus pedunculatus and Medicago sativa, and effects of extractable condensed tannin fractions on methanogenesis. Animal Feed Science and Technology 123, 403–419.Google Scholar
Tessema, Z, Baars, RMT 2004. Chemical composition, in vitro dry matter digestibility and ruminal degradation of Napier grass (Pennisetum purpureum (L.) Schumach.) mixed with different levels of Sesbania sesban (L.) Merr. Animal Feed Science and Technology 117, 29–41.Google Scholar
Thalib, A, Widiawati, Y, Hamid, H, Suherman, D, Sabrani, M 1996. The effects of saponins from Sapindus rarak fruit on rumen microbes and performance of sheep. Jurnal Ilmu Ternak dan Veteriner 2, 17–21.Google Scholar
Theodorou, MK, Williams, BA, Dhanoa, MS, McAllan, AB, France, J 1994. A simple gas production method using a pressure transducer to determine the fermentation kinetics of ruminant feeds. Animal Feed Science and Technology 48, 185–197.CrossRefGoogle Scholar
Tilman, D, Wedin, D, Knops, J 1996. Productivity and sustainability influenced by biodiversity in grassland ecosystems. Nature 379, 718–720.Google Scholar
Van Soest, PJ 1982. Nutritional ecology of the ruminant animal. O & B Books, Inc., Corvallis, OR, USA.Google Scholar
Van Soest, PJ 1994. Nutritional Ecology of the Ruminant, 2nd edition. Cornell University Press, Ithaca, NY, USA.CrossRefGoogle Scholar
Vermorel, M, Jouany, JP 1989. Effects of rumen protozoa on energy utilization by wethers of two diets based on ammonia-treated straw supplemented or not with maize. Asian-Australasian Journal of Animal Sciences 2, 475–476.Google Scholar
Waghorn, G 2008. Beneficial and detrimental effects of dietary condensed tannins for sustainable sheep and goat production. Progress and challenges. Animal Feed Science and Technology 147, 116–139.Google Scholar
Waghorn, GC, Shelton, ID, Thomas, VJ 1989. Particle breakdown and rumen digestion of fresh ryegrass (Lolium perenne L.) and lucerne (Medicago sativa L.) fed to cows during a restricted feeding period. British Journal of Nutrition 61, 409–423.CrossRefGoogle ScholarPubMed
Waghorn, G, Tavendale, M, Woodfield, D 2002. Methanogenesis from forages fed to sheep. Proceedings of the New Zealand Grassland Association 64, 167–171.Google Scholar
Wallace, RJ 2004. Antimicrobial properties of plant secondary metabolites. Proceedings of the Nutrition Society 63, 621–629.Google Scholar
Wallace, RJ, McEwan, NR, McIntosh, FM, Teferedegne, B, Newbold, CJ 2002. Natural products as manipulators of rumen fermentation. Asian-Australasian Journal of Animal Sciences 15, 1458–1468.CrossRefGoogle Scholar
Wang, Y, McAllister, TA, Yanke, LJ, Cheeke, PR 2000. Effect of steroidal saponin from Yucca schidigera extract on ruminal microbes. Journal of Applied Microbiology 88, 887–896.Google Scholar