Changes of Nitrogen Compounds During Ensiling of High Protein Herbages – A Review

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Losses of crude protein during ensiling of herbages, in contrast to carbohydrates, do not affect the reduction of its content; their form is changed into greater solubility non-protein compounds and also highly degraded forms, which lower the efficiency of the microbial protein synthesis in the rumen. These processes are accompanied by a change of amino acid composition of herbage protein and decrease in intestinal digestibility of protein from feeds as a result of the formation of indigestible complexes with carbohydrates (ADIN). Reduction of protein degradation in silages is achieved by accelerated acidity through addition of acids or dominance of homofermentative bacteria. The positive effects of fermentation inhibitors or sorbents use, as well as the wilting of raw material on the level and rate of protein degradation were demonstrated by many researchers. A greater contribution of protein nitrogen and reduction of deamination in silages can also be obtained by using bacteria inoculants. Increasing the proportion of protein nitrogen is accompanied by the improved efficiency of microbial protein synthesis.

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  • Albrecht K.A. Muck R.E. (1991). Proteolysis in ensiled forage legumes that vary in tannin con­centration. Crop Sci. 31: 464-469.

  • Arrigo Y. (2006). Influence du cycle du state et du mode de conservation sur la teneur en acides amines des fourrages. Rev. Suisse Agric. 38: 247-255.

  • Barry T.N. M c N a b b W.C. (1999). The implication of condensed tannins on the nutritive value of temperate forages to ruminants. Brit. J. Nutr. 81: 263-272.

  • Broderick G.A. Yang J.H. Koegel R.G. (1993). Effect of steam heating alfalfa hay on utiliza­tion by lactating dairy cows. J. Dairy Sci. 76: 165.

  • Brzóska F. Sala K. Kryszczak M. (1994). Effect of mineral and organic acid salts mix­ture on fermentation profiles and silage chemical composition (in Polish). Rocz. Nauk. Zoot. 21: 215-226.

  • Brzóska F. Wiewiora W. Gąsior R. Brzóska B. (1995 a). Effect of chemical preservatives on the nutritional values of grass silages cow productivity and milk composition (in Polish). Rocz. Nauk. Zoot. 22: 149-162.

  • Brzóska F. Zyzak W. Sala K. (1995 b). Effect of mixtures of organic acid and mineral acid salts nutritive value of grass silages cow productivity and milk composition (in Polish). Rocz. Nauk. Zoot. 22: 183-195.

  • Brzóska F. Pieszka M. Sala K. (1999). Effect of dry matter and fermentation supplements on the chemical composition and protein degradation in lucerne silages (in Polish). Rocz. Nauk. Zoot. - Ann. Anim. Sci. 26: 231-242.

  • Burggraaf V. Waghorn G. Woodward S. Thom E. (2008). Effects of condensed tannins in white clover flowers on their digestion in vitro. Anim. Feed Sci. Tech. 142: 44-58.

  • Buxton D.R. O’Kiely P. (2003). Preharvest plant factors affecting ensiling. In: Buxton D.R. Muck R.E. Harrison J.H. (eds). In: Silage Science and Technology. Wisconsin USA American Society of Agronomy pp. 199-250.

  • Cavallarin L. Antoniazzi S. Borreani G. Tabacco E. (2005). Effects of wilting and mechanical conditioning on proteolysis in sainfoin (Onobrychis viciifolia Scop) wilted herbage and silage. J. Sci. Food Agr. 85: 831-838.

  • Charmley E. Veira D.M. (1990). Inhibition of proteolysis in alfalfa silages using heat at har­vest: effects on digestion in rumen voluntary intake and animal performance. J. Anim. Sci. 68: 2042-2051.

  • Charmley E. Veira D.M. (1991). The effect of heat-treatment and gamma-irradiation on the com­position of unwilted lucerne silages. Grass Forage Sci. 46: 381-390.

  • Chiquette J. Cheng K.J. Rode L.M. Milligan L.P. (1989). Effect of tannin content in two isosynthetic strains of birdsfoot trefoil (Lotus corniculatus) on feed digestibility and rumen fluid composition in sheep. Can. J. Anim. Sci. 69: 1031-1039.

  • Chopin A. (1993). Organization and regulation of genes for amino acid biosynthesis in lactic acid bacteria. FEMS Microbiol. Rev. 12: 21-38.

  • Coblentz W.K. Grabber J.H. (2013). In situ protein degradation of alfalfa and birdsfoot trefoil hays and silages as influenced by condensed tannin concentration. J. Dairy Sci. 96: 3120-3137.

  • Copani G. Ginane C. Le Morvan A. Niderkorn V. (2014). Bioactive forage legumes as a strategy to improve silage quality and minimise nitrogenous losses. Anim. Prod. Sci. 54: 1826-1829.

  • Davies D.R. Merry R.J. Williams A.P. Bakewell E.L. Leemans D.K. Tweed J.K. (1998). Proteolysis during ensilage of forages varying in soluble sugar content. J. Dairy Sci. 81: 444-453.

  • Davies D.R. Winters A.L. Leemans D.K. Dhanoa M.S. Merry R.J. (1999). The effect of inoculant treatment of alternative crop forages on silage quality and in vitro rumen function. Proc. XIIth International Silage Conference Uppsala Sweden 2-4.07.2012 pp. 131-132.

  • Davies D.R. Theodorou M.K. Kingston-Smith A.H. Merry R.J. (2005). Advances in silage quality in the 21st century. Proc. XIVth International Silage Conference Belfast Northern Ireland 05.2005 pp. 121-133.

  • Dawson L.E.R. Ferris C.P. Steen R.W.J. Gordon F.J. Ki l patr i c D.J. (1999). The effects of wilting grass before ensiling on silage intake. Grass Forage Sci. 54: 237-247.

  • Dewhurst R.J. Mitton A.M. Offer N.W. Thomas C. (1996). Effects of the composition of grass silages on milk production and nitrogen utilization by dairy cows. Anim. Sci. 62: 25-34.

  • Dewhurst R.J. Scollan N.D. Moorby J.M. Evans R.T. Merry R.J. Wilkins R.J. (2003). Comparison of grass and legume silages for milk production. 2. In vivo and in sacco evalu­ations of rumen function. J. Dairy Sci. 86: 2612-2621.

  • Dorszewski P.A. (2009). The effectiveness of the use of silage additives in the preservation of legume-grass mixture and whole maize herbages (in Polish). Dissertations no 136. Wydawnictwa Uczelniane Uniwersytetu Technologiczno-Przyrodniczego.

  • Duniere L. Sindou J. Chaucheyras-Durand F. Chevallier I. Thevenot-Ser- g e n t e t D. (2013). Silage processing and strategies to prevent persistence of undesirable microor­ganisms. Anim. Feed Sci. Tech. 183: 1-15.

  • Edmunds B. Spiekers H. Sudekum K.-H. Nussbaum H. Schwarz F.J. Ben­ nett R. (2012). Effect of extent and rate of wilting on nitrogen components of grass silage. Grass Forage Sci. 69: 140-152.

  • Elizalde J.C. Merchen N.R. Faulkner D.B. (1999). Fractionation of fiber and crude protein in fresh forages during the spring growth. J. Anim. Sci. 77: 476-484.

  • Frank B. Persson M. Gustafsson G. (2002). Feeding dairy cows for decreased ammonia emission. Livest. Prod. Sci. 76: 171-179.

  • Frutos P. Hervas G. G i r a l d e z F.J. Mantecon A.R. (2004). Review. Tannins and ruminant nutrition. Span. J. Agric. Res. 2: 191-202.

  • Gąsior R. Brzóska F. (1999). The type and level of biogenic amines in alfalfa and red clover silage (in Polish). Zesz. Nauk. AR Krakow 347: 89-94.

  • Gąsior R. Brzóska F. (2002). Biogenic amines in silages (in Polish). Adv. Agr. Sci. 2: 115-128.

  • Getachew G. Makkar H.P.S. Becker K. (2001). Method of polyethylene glycol application to tannin-containing browses to improve microbial fermentation and efficiency of microbial protein synthesis from tannin containing browses. Anim. Feed Sci. Tech. 92: 51-57.

  • Givens D.I. Rulquin H. (2004). Utilization by ruminants of nitrogen compounds in silage-based diets. Anim. Feed Sci. Tech. 114: 1-18.

  • Grabber J.H. (2009). Forage management effects on protein and fiber fractions protein degradability and dry matter yield of red clover conserved silage. Anim. Feed Sci. Tech. 154: 284-291.

  • Grabber J.H. Coblentz W.K. (2009). Polyphenol conditioning and conservation effects on pro­tein fractions and degradability in forage legumes. Crop Sci. 49: 1511-1522.

  • Guo X. Zhou H. Yu Z. Zhang Y. (2007). Changes in the distribution of nitrogen and plant en­zymatic activity during ensilage of lucerne treated with different additives. Grass Forage Sci. 62: 35-43.

  • Guo X.S. Ding W.R. Han J.G. Zhou H. (2008). Characterization of protein fractions and ami­no acids in ensiled alfalfa treated with different chemical additives. Anim. Feed Sci. Tech. 142: 89-98.

  • Guo X.S. Cheng W. Zhang Y. Yang F.Y. Zhou H. (2011). Contribution of endopeptidases to the formation of nonprotein nitrogen during ensiling of alfalfa. Anim. Feed Sci. Tech. 168: 42-50.

  • Hedqvist H. Uden P. (2006). Measurement of soluble protein degradation in the rumen. Anim. Feed Sci. Tech. 126: 1-21.

  • Hegazi F.Z. (1987). Proteolytic activity of lactic acid bacteria in skim milk with special reference to the biodegradation of casein fractions. Nahrung. 31: 19-26.

  • Heron S. Edwards R.E. McDonald P. (1986). Changes in the nitrogenous components of gamma-irradiated and inoculated ensiled ryegrass. J. Sci. Food Agric. 37: 979-985.

  • Hertig D. Potkanski A. (2001). The effect of additives on carbohydrate content of grass and legume silages (in Polish). Ann. Anim. Sci. 13: 35-40.

  • Hristov A.N. Sandev S.G. (1998). Proteolysis and rumen degradability of protein in alfalfa pre­served as silage wilted silage or hay. Anim. Feed Sci. Tech. 72: 175-181.

  • Huhtanen P. (2010). Evaluation of protein value of forages. Proc. 14th International Symposium “Forage Conservation” Brno 17-19.03.2010 pp. 58-76.

  • Huhtanen P. Shingfield K.J. (2005). Grass silage: factors affecting efficiency N utilization in milk production. Proc. XIVth International Silage Conference Belfast Northern Ireland 07.2005 pp. 35-51.

  • Hymes-Fecht U.C. Broderick G.A. Muck R.E. Grabber J.H. (2013). Replacing alfalfa or red clover silage with birdsfoot trefoil silage in total mixed rations increases production of lactat- ing dairy cows. J. Dairy Sci. 96: 460-69.

  • IZ PIB-INRA (2009). Standards for ruminant feeding. The nutritional value of the French and the na­tional feeds for ruminants (J. Strzetelski ed.) IZ PIB Krakow.

  • Johansson M. Bagge E. Thylin I. Albihn A. (2002). Hygienic quality in grass silage in re­lation to dry matter content of the crop. Proc. XIIIth International Silage Conference Auchincruive Scotland pp. 404-405.

  • Jones R. (2000). Understanding the processes of protein degradation in forage crops provide opportu­nities for improved silage quality and enhanced animal production. Proc. Alltech’s Sixteenth Annual Symposium Lyons T.P. and Jacques K.A. (eds). Nottingham University Press pp. 423-437.

  • Jones B.A. Muck R.E. Hatfield R.D. (1995). Red clover extracts inhibit legume proteolysis. J. Sci. Food Agr. 67: 329-333.

  • Kemble A.R. Macpherson H.T. (1954). Liberation of amino acids in perennial rye grass during wilting. Biochem. J. 58: 46.

  • King C. McEniry J. O’Kiely P. (2012). A note on the fermentation characteristics of red clover silage in response to advancing stage of maturity in the primary growth. Irish J. Agr. Food Res. 51: 79-84.

  • Krizsan S.J. Randb y A.T. (2007). The effect of fermentation quality on the voluntary intake of grass silage by growing cattle fed silage as the sole feed. J. Anim. Sci. 85: 984-996.

  • Krzywiecki S. Pres J. Bodarski R. (2008). The importance of microbiological and physico­chemical processes in the practice of ensiling forage in German research (in Polish). Pam. Pul. 147: 139-150.

  • Kung L. Jr. Stockes M.R. Lin C.J. (2003). Silage additives. In: Silage Science and Technology Buxton D.R. Muck R.E Harrison J.H. (eds). Agronomy Series 42 Madison Wisconsin USA pp. 305-360.

  • Kung L. Jr. Muck R.E. (2006). Preservation of protein during harvest and storage. J. Dairy Sci. 89 (Suppl. 1): 449.

  • Kunji E.R.S. Mierau I. Hagting A. Poolman B. Konings W.N. (1996). The proteolytic system of lactic acid bacteria. A. Van Leeuw. J. Microb. 70: 187-221.

  • Lee M.R.F. Winters A.L. Scollan N.D. Dewhurst R.J. Theodorou M.K. Minchin F.R. (2004). Plant-mediated lipolysis and proteolysis in red clover with different polyphenol oxidase activites. J. Sci. Food Agr. 84: 1639-1645.

  • Lee M.R.F. Olmos Colmenero J.J. Winters A.L. Scollan N.D. Min chin F.R. (2006). Polyphenol oxidase activity in grass and its effect on plant-mediated lipolysis and prote­olysis of Dactylis glomerata (cocksfoot) in a simulated rumen environment. J. Sci. Food Agr. 86: 1503-1511.

  • Lee M.R.F. Scott M.B. Tweed J.K.S. M in ch in F.R. Davies D.R. (2008). Effects of poly­phenol oxidase on lipolysis and proteolysis of red clover silage with and without a silage inoculant (Lactobacillus plantarum L54). Anim. Feed Sci. Tech. 144: 125-136.

  • Lee M.R.F. Tweed J.K.S. Sullivan M.L. (2012). Oxidation of ortho-diphenols in red clover with and without polyphenol oxidase (PPO) activity and their role in PPO activation. Grass Forage Sci. 68: 83-92.

  • Licitra G. Hernandez T.M. Van Soest P.J. (1996). Standardization of procedure for nitrogen fractionation of ruminant feeds. Anim. Feed Sci. Tech. 57: 347-358.

  • Lin C. Bolsen K.K. Brent B.E. Hart R.A. Dickerson J.T. Feyerherm A.M. Aimutis W.R. (1992). Epiphytic microflora of alfalfa and whole-plant corn. J. Dairy Sci. 75: 2484-2493.

  • Lindgren S. (1999). Can HACCP principles be applied for silage safety? Silage production in rela­tion to animal performance animal health meat and milk quality. Proc. XIIth International Silage Conference Uppsala Sweden pp. 51-66.

  • Lorenz M.M. Eriksson T. Uden P. (2010). Effect ofwilting silage additive PEG treatment and tannin content on the distribution of N between different fractions after ensiling of three different sainfoin (Onobrychis viciifolia) varieties. Grass Forage Sci. 65: 175-184.

  • Lorenz M.M. Uden P. (2011). Influence of formic acid and dry matter on protein degradation in the tanniniferous legume sainfoin. Anim. Feed Sci. Tech. 164: 217-224.

  • Luchini N.D. Broderick G.A. Muck R.E. Makoni N.F. Vetter R.L. (1997). Effect of storage system and dry matter content on the composition of alfalfa silage. J. Dairy Sci. 80: 1827-1832.

  • Macpherson H.T. Slater J.S. (1959). y-amino-n-butyric aspartic glutamic and pyrrolidonecar- boxylic acid; their determination and occurrence in grass during conservation. Biochem. J. 71: 654-660.

  • Martineau R. Lapierre H. Ouellet D.R. Pellerin D. Berthiaume R. (2007). Effects of the method of conservation of timothy on nitrogen metabolism in lactating dairy cows. J. Dairy Sci. 90: 2870-2882.

  • McDonald P. Henderson A.R. Heron S.J.E. (1991). The Biochemistry of Silage. Chalcombe Publications Marlow Bucks UK 2nd ed.

  • McKersie B.D. (1985). Effect of pH on proteolysis in ensiled legume forage. Agron. J. 77: 81-86.

  • Merry R.J. Lowes K.F. Winters A.L. (1997). Current and future approaches to biocontrol in silage Jambor V. Klapil L. Chromec P. Prochazka P. (eds). Proc. 8th International Symposium on Forage Conservation Brno Research Institute of Animal Nutrition Ltd. Pohorelice Czech Repu­blic pp. 17-27.

  • Michalska A. Zielinski H. (2007). The Maillard reaction products in food. Food. Science. Tech­nology. Quality 51: 5-16.

  • Min B.R. Barry T.N. Attwood G.T. McNabb W.C. (2003). The effect of condensed tannins on the nutrition and health of ruminants fed fresh temperate forages: a review. Anim. Feed Sci. Tech. 106: 3-19.

  • Moorby J.M. Dewhurst R.T. Evans R.T. Fisher W.J. (2002). Effects of varying the energy and protein supply to dry cows on high forage systems. Livest. Prod. Sci. 76: 125-136.

  • Morishita T. Deguchi Y. Yajima M. Sakurai T. Yura T. (1981). Multiple nutritional requirements of lactobacilli: genetic lesions affecting amino acid synthetic pathways. J. Bacteriol. 148: 64-71.

  • Muck R.E. Dickerson J.T. (1988). Storage temperature effects on proteolysis in alfalfa silage. T. ASAE 31: 1005-1009.

  • Nadeau E.M.G. Buxton D.R. Russel J.R. Allison M.J. Young J.W. (2000). Enzyme bacterial inoculant and formic acid effects on silage composition of orchadgrass and alfalfa. J. Dairy Sci. 83: 1487-1502.

  • Nadeau E. Englund J.E. Gustafsson A.H. (2007). Nitrogen efficiency of dairy cows as af­fected by diet and milk yield. Livest. Sci. 111: 45-46.

  • Nadeau E. Richardt W. Murphy M. Auerbach H. (2012). Protein quality dynamics dur­ing wilting and preservation of grass-legume forage. Proc. XVIth International Silage Conference Hameenlinna Finland 2-4.07.2012 pp. 56-57.

  • Nagel S.A. Broderick G.A. (1992). Effect of formic acid or formaldehyde treatment of alfalfa silage on nutrient utilization by dairy cows. J. Dairy Sci. 75: 140-154.

  • Nsereko V.L. Rooke J.A. Newbold C.J. Wallace R.J. (1998). Influence of protease inhibi­tors on nitrogen distribution in ensiled perennial ryegrass and the utilisation of silage nitrogen for growth by rumen bacteria in vitro. Anim. Feed Sci. Tech. 76: 51-63.

  • Ohshima M. McDonald P. (1978). A review of the changes in nitrogenous compounds of herbage during ensilage. J. Sci. Food Agr. 29: 497-505.

  • Owens V.N. Albrecht K.A. Muck R.E. Duke S.H. (1999). Protein degradation and fermen­tation characteristics of red clover and alfalfa silage harvested with varying levels of total non­structural carbohydrates. Crop Sci. 39: 1873-1880.

  • Papadopoulos Y.A. McKersie B.D. (1983). A comparison of protein degradation during wilt­ing and ensiling of six forage species. Can. J. Plant Sci. 63: 903-912.

  • Pitt R.E. Muck R.E. Leiben sperger R.Y. (1985). A quantitative model ofthe ensilage process in lactate silages. Grass Forage Sci. 40: 279-303.

  • Polan C.E. Stieve D.E. Garrett J.L. (1998). Protein preservation and ruminal degradation of ensiled forage treated with heat formic acid ammonia or microbial inoculant. J. Dairy Sci. 81: 765-776.

  • Potkanski A. Gulewicz K. Michalak S. (2002). Effect of tannins on the degradability of protein silages in the rumen. Proc. XIIIth International Silage Conference Auchincruive Scotland pp. 306-307.

  • Purwin C Laniewska-Trokenheim L. Warminska-Radyko I. Tywonczuk J. (2006). The quality of silage - microbiological health and production aspects (in Polish). Med. Weter. 62: 865-869.

  • Purwin C Pysera B. Tokarczyk M. Sederevicius A. Savickis S. Traidaraite A. (2009). Production results of dairy cows fed grass and alfalfa silage with a different degree of wilting. Vet. Zootec. 46: 60-66.

  • Purwin C.PyseraB. Sederevicius A. Makauskas S.Traidaraite A. LipinskiK. (2010). Effect of silage made from different plant raw materials with the addition of fermentation inhibitor on the production results of dairy cows. Vet. Zootec. 51: 44-51.

  • Purwin C Fijafkowska M. Pysera B.Lipinski K. Sienkiewicz S. Piwczynski D. Puzio N. (2014 a). Nitrogen fractions and amino acid content in alfalfa and red clover im­mediately after cutting and after wilting in the field. J. Elem. 19: 723-734.

  • Purwin C Fijafkowska M. Kowalik B. Skorko-SajkoH.NogalskiZ. PyseraB. (2014 b). The effect of bale density and the addition of formic acid on the in situ dry matter and crude protein degradation of lucerne red clover and red fescue silages. J. Anim. Feed Sci. 23: 177-184.

  • Purwin C Fijafkowska M. Li pin ski K. Wierzbowska J. Kobzhassarov T.Z. Michalski J. (2015). Changes in amino acid composition during ensiling lucerne and red clover in round bales. J. Elem. (in press).

  • Pys J.B. Borowiec F. Furgal K. Kaminski J. Zając T. (2000). The effect of bacterial inoculant glucose and lactic acid on the quality and chemical composition of alfalfa silage Medicago sativa Pers and Medicago sativa L. (in Polish). Acta Agr. Silv. ser. Zootech. 38: 3-15.

  • Randby A.T. (2000). The effect of some acid-based additives applied to wet grass crops under various ensiling conditions. Grass Forage Sci. 55: 289-299.

  • Sasaki M. Bosman B.W. Tan P.S.T. (1995). Comparison of proteolytic activities in various Lac­tobacilli. J. Dairy Res. 62: 601-610.

  • Scalet M. Alpi A. Picciarelli P. (1984). Proteolytic activities in alfalfa (Medicago sativa L.) leaves. J. Plant Physiol. 116: 133-145.

  • Schwab C.G. Tylutki T.P. Ordway R.S. Sheaffer C. Stern M.D. (2003). Characteriza­tion of proteins in feeds. J. Dairy Sci. 86(E. Suppl.): E88-E103.

  • Slottner D. Bertilsson J. (2006). Effect of ensiling on protein degradation during ensilage. Anim. Feed Sci. Tech. 127: 101-111.

  • Sniffen C.J. O'Connor J.D. Van Soest P.J. Fox D.G. Russel J.B. (1992). A net car­bohydrate and protein system for evaluating cattle diets. II. Carbohydrate and protein availability. J. Anim. Sci. 70: 3562-3577.

  • Stallings C.C. Townes R. Jesse B.W. Thomas J.W. (1981). Changes in alfalfa haylage during wilting and ensiling with and without additives. J. Anim. Sci. 53: 765-773.

  • Sullivan M.L. Hatfield R.D. (2006). Polyphenol oxidase and o-diphenols inhibit postharvest proteolysis in red clover and alfalfa. Crop Sci. 46: 662-670.

  • Theodoridou K. Aufrere J. Andueza D. Le Morvan A. Picard F. Pourrat J. Baumont R. (2012). Effects of condensed tannins in wrapped silage bales of sainfoin (Onobry- chis viciifolia) on in vivo and in situ digestion in sheep. Animal 6: 245-253.

  • Van Boven A. Konigs W.N. (1988). Utilization of dipeptides by Lactococcus lactis ssp. cremo- ris. Biochemie 70: 535-542.

  • Van Vuuren A.M. (1993). Digestion and nitrogen metabolism of grass fed dairy cows. Ph.D. diss. Landbouwuniversiteit te Wageningen The Netherlands.

  • Wagh orn G.C. Uly att M.J. John A. Fisher M.T. (1987). The effect of condensed tannins on the site of digestion of amino acids and other nutrients in sheep fed on Lotus corniculatus L. Brit. J. Nutr. 57: 115-126.

  • Weinberg Z.G. Muck R.E. (1996). New trends and opportunities in the development and use of inoculants for silage. FEMS Microbiol. Rev. 19: 53-68.

  • Wilkins R.J. (1984). A review of the effects of wilting on the composition and feeding values of silages. In: Efficency of silage systems: a comparison between unwilted and wilted silages Zimmer E. and Wilkins R.J. (eds). Landbauforshung Volkenrode Sonderheft 69: 71-77.

  • Winters A.L. M inch in F.R. (2001). Red clover and the future for pasture legumes as an alterna­tive protein source for ruminants. IGER Innovations 5: 30-33.

  • Winters A.L. Fychan R. Jones R. (2001). Effect of formic acid and a bacterial inoculant on the amino acid composition of grass silage and on animal performance. Grass Forage Sci. 56: 181-192.

  • Woolford M.K. (1984). Silage fermentation. New York Marcel Decker.

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