Grassland legumes are essential in organic ruminant livestock production due to their ability to fix atmospheric nitrogen (N), providing high yields of high feeding value without N fertilization. White clover (Trifolium repens L.) and red clover (Trifolium pratense L.) are the most important legumes of temperate grasslands with white clover as the most widely used. New research has reviled new properties of red clover that may affect animal performance and product quality significantly. Red clover containing diets have increased the production of milk and meat (compared with grasses) and the content of beneficial fatty acids in milk and meat (compared with grasses and other legumes), improved the efficiency of feed N utilization (compared with Medicago sativa L.), and increased the milk content of isoflavones (compared with grass and white clover). Red clover contains high levels of the enzyme polyphenol oxidase that might reduce the extent of lipolysis and proteolysis. The paper presents a review on resent results from own and others’ research on the use of red clover in the diet of ruminants and the likely mechanisms by which red clover affects production and product qualit

Steinshamn, Håvard

English

Organic Eprints

1st Scientific Conference within the framework of the 8th European Summer Academy on Organic Farming, Lednice na Moravě, Czech Republic, September 3–5, 2008    The unique properties of red clover in the diet of ruminants  Steinshamn, H.1 Key words: red clover, ruminants, meat, milk, fatty acids, organic farming Abstract  Grassland legumes are essential in organic ruminant livestock production due to their ability  to  fix  atmospheric  nitrogen  (N),  providing  high  yields  of  high  feeding  value without  N  fertilization.  White  clover  (Trifolium  repens  L.)  and  red  clover  (Trifolium pratense  L.)  are  the  most  important  legumes  of  temperate  grasslands  with  white clover as the most widely used. New research has reviled new properties of red clover that  may  affect  animal  performance  and  product  quality  significantly.  Red  clover containing  diets  have  increased  the  production  of  milk  and  meat  (compared  with grasses) and the content of beneficial fatty acids in milk and meat (compared with grasses and other legumes), improved the efficiency of feed N utilization (compared with Medicago sativa L.), and increased the milk content of isoflavones (compared with  grass  and  white  clover).  Red  clover  contains  high  levels  of  the  enzyme polyphenol oxidase that might reduce the extent of lipolysis and proteolysis. The paper presents a review on resent results from own and others’ research on the use of red clover in the diet of ruminants and the likely mechanisms by which red clover affects production and product quality.      Introduction  Legumes  are  essential  in  organic  agriculture  due  to  their  ability  to  fix  atmospheric nitrogen (N) and thereby determine to a large extent the productivity of the system. In organic  grassland  livestock  farming,  the  perennial  legumes  not  only  ensure  the  N input, they also provides high quality fodder. It is recognized that grassland legumes have superior feeding value with higher intake and animal production than grasses (Frame et al., 1998). White clover (Trifolium repens L.), lucerne (Medicago sativa L.), and  red  clover  (Trifolium  pratense  L.)  are  the  most  widely  cultivated  grassland legumes with the white clover as the most important in Europe. In recent years, the interest  for  red  clover  has  increased,  partly  because  red  clover  possesses  unique properties that may affect animal performance and product quality. In this paper, some recent published research with red clover and its effect on animal performance and animal products (milk and meat) is reviewed.   Animal performance  Early experiments with red clover silage fed to beef and dairy cows demonstrated higher feed intake and performance (growth rate, milk yield) than pure grass silage (Thomas et al., 1981; Thomas et al., 1985). These results have been confirmed in more recent experiments with dairy cows (Dewhurst et al., 2003b; Vanhatalo et al., 2006), and Fraser et al. (2004) observed higher growth rate in lamb grazing red clover                                                  1 Bioforsk   Norwegian Institute for Agricultural and Environmental Research, Organic Food and Farming, Tingvoll gard, 6630 Tingvoll, Norway, E Mail havard.steinshamn@bioforsk.no, Internet www.bioforsk.no 1st Scientific Conference within the framework of the 8th European Summer Academy on Organic Farming, Lednice na Moravě, Czech Republic, September 3–5, 2008    than  on  perennial  ryegrass  (Lolium  perenne  L.).  Others  have  found  only  small  differences or that differences between red clover and grasses depended on seasonal growth  conditions  (Bertilsson  and  Murphy,  2003;  van  Dorland  et  al.,  2006).  The positive effect of red clover relative to grass has been explained by higher voluntary intake  at  similar  digestibility.  Higher  voluntary  intake  is  ascribed  to  higher concentration of cell contents in red clover than in grasses resulting in faster rates of particle breakdown in the rumen and more rapid clearance of particles from the rumen (Frame et al., 1998).    More recently, red clover has been compared with other legumes. Red clover silage has often proved to be superior to lucerne silage in relation to milk yield relative to feed intake (Broderick et al., 2001; Dewhurst et al., 2003b; Hoffman et al., 1997), and lamb grazing red clover had higher live weight gain than those grazing lucerne (Fraser et al., 2004). Broderick et al. (2001) estimated from animal performance data that the net energy of lactation was 18 % greater in red clover than lucerne. Red and white clover are to a large extent equivalent in usable energy and protein supply, as only minor differences in feed intake and milk yield have been observed when compared (Bertilsson and Murphy, 2003; Dewhurst et al., 2003b; Steinshamn and Thuen, 2008; van Dorland et al., 2006).  Red clover containing diets have increased ruminal non ammonia N flow in terms of increased flows of microbial and dietary N entering the small intestine when compared with grass silage (Dewhurst et al., 2003a; Vanhatalo et al., 2006) and with lucerne. Consequently,  higher  apparent  N  conversion  from  feed  N  to  product  N  is  often observed on red clover than on grasses or lucerne (Broderick et al., 2001; Vanhatalo et al., 2006). However, due to high N content improved N efficiency relative to grasses or other legumes are not consistent (Bertilsson and Murphy, 2003; van Dorland et al., 2006). This inconsistency warrants further research. Product quality  Only small and inconsistent effect of red clover has been reported on the milk content of fat, protein and lactose. However, red clover seems to have a pronounced effect on the milk and meat fatty acids composition. Red clover containing diets has increased the product content of polyunsaturated fatty acids, particularly of the beneficial alpha linolenic acid (C18:3n 3), both when compared with grasses and other legumes (Table 1, Al Mabruk et al., 2004; Dewhurst et al., 2003b; Fraser et al., 2004; Steinshamn and Thuen, 2008; Vanhatalo et al., 2007). The inclusion of red clover in the diet of dairy cows  is  likely  an  important  explanation  for  the  often  observed  higher  content  of nutritional desirable fatty acids in organic than in conventional produced milk (Butler et al., 2008; Ellis et al., 2006).   Another striking feature with red clover is the high content of phytoestrogens of the isoflavone group. In a dairy cow experiment with organic managed cows, Steinshamn et al. (2008)  found that milk content of biochanin A (1.86 vs. 0.37  g/l), equol (318 vs. 75   g/l), and formononetin (6.5 vs. 2.7  g/l) were several times higher on red clover than on white clover containing silage diets. Phytoestrogens, and particularly equol, may have beneficial health effect, and increased content in milk may be important when health benefits of milk are studied.     1st Scientific Conference within the framework of the 8th European Summer Academy on Organic Farming, Lednice na Moravě, Czech Republic, September 3–5, 2008    Tab. 1: Milk content of alfa-linolenic acid (% of total milk fatty acids) of dairy cows fed either grass, white clover (WC) or red clover (RC) silages Reference  Grass  WC  RC  Grass vs clover  WC vs RC Al Mabruk et al. 2003  0.47    0.93  ***   Dewhurst et al. 2003b  0.40  0.96  1.28  ***  *** Vanhatalo et al. 2007  0.39    1.11  ***   Van Dorland et al. 2008  0.90  1.14  1.04  (*)  ns Steinshamn and Thuen 2008    0.73  0.87    ***  (*) significant for P<0.10  *** significant for P<0.001 Plant mechanism explaining the red clover effect  Red clover contains high levels of both the enzyme polyphenol oxidase (PPO) and its subtrate o diphenol. PPO convert phenols to quinones, which bind with proteins and reduces proteolysis and lipolysis in silo and in rumen (Albrecht and Muck, 1991; Lee et al., 2007; Sullivan and Hatfield, 2006). Proteolysis and lipolysis are catalyzed by the enzymes protease and lipase. These enzymes are proteins, and the quinones formed after harvesting binds to the enzymes and partly denaturalize them. The result is that more of the original plant protein remains intact after ensiling and rumen passage, explaining higher conversion of feed N into meat or milk N on red clover than on other forages. Likewise, reduced lipolysis results in reduced rumen biohydrogenation of fatty acids. Consequently, a higher proportion of the unsaturated fatty acids in the ingested feed passes the rumen to the intestine for absorption. Thus, a higher transfer rate of C18:3n 3 from feed to milk is observed on red clover diets (Dewhurst et al. 2003b; Steinshamn and Thuen, 2008).  Conclusions  Red clover has superior feeding value and higher ruminant performances (higher milk yield and growth rate) are often obtained when compared with grasses and lucerne. Red  clover  contains  high  amounts  of  polyphenol  oxidase  (PPO)  and  its  phenolic substrate.  High  PPO  activity  reduces  proteolysis  and  lypolisis,  which  is  the  likely mechanism for improved conversion of feed N into product N and to higher transfer of polyunsaturated  fatty  acids  from  feed  to  product.  Red  clover  also  contains  high amounts of isoflavonoids, which is reflected in milk from dairy cows fed red clover containing diets.   References  Al Mabruk R. M., Beck N. F. G., Dewhurst R. J. (2004): Effects of silage Species and supplemental vitamin E on the oxidative stability of milk. J. Dairy Sci. 87:406 412. Albrecht K. A., Muck R.E. (1991): Proteolysis in ensiled forage legumes that vary in tannin concentration. Crop Sci. 31:464 469. Bertilsson J., Murphy M. (2003): Effects of feeding clover silages on feed intake, milk production and digestion in dairy cows. Grass Forage Sci. 58:309 322. Broderick G. A., Walgenbach R. P., Maignan S. (2001): Production of lactating dairy cows fed alfalfa or red clover silage at equal dry matter or crude protein contents in the diet. J. Dairy Sci. 84:1728 1737. 1st Scientific Conference within the framework of the 8th European Summer Academy on Organic Farming, Lednice na Moravě, Czech Republic, September 3–5, 2008    Butler G., Nielsen J.H., Slots T., Eyre M.D., Sanderson R., Leifert C. 2008. Fatty acid and fat soluble antioxidant concentrations in milk from high  and low input conventional and organic systems: seasonal variation. J. Sci. Food Agric. 88:1431 1441. Dewhurst R. J., Evans, R.T., Scollan, N.D., Moorby J.M., Merry R,J., Wilkins R.J. (2003a): 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. Dewhurst R. J., Fisher W.J., Tweed J.K.S., Wilkins R.J. (2003b): Comparison of grass and legume silages for milk production. 1. Production responses with different levels of concentrate. J. Dairy Sci. 86:2598 2611. Ellis K. A., Innocent G., Grove White D., Cripps P., McLean W.G., Howard C.V., Mihm M. (2006): Comparing the fatty acid composition of organic and conventional milk. J. Dairy Sci. 89:1938 1950. Frame J., Charlton J.F.L., Laidlaw A.S. (1998): Temperate forage legumes.  CAB International, Wallingford. 327 p. Fraser M. D., Speijers M.H.M., Theobald V.J., Fychan R., Jones R. (2004): Production performance and meat quality of grazing lambs finished on red clover, lucerne or perennial ryegrass swards. Grass Forage Sci. 59:345 356. Hoffman P. C., Combs D.K., Brehm N.M., Welch D.A. (1997): Performance of lactating dairy cows fed red clover or alfalfa silage. J. Dairy Sci. 80:3308 3315. Lee M. R., Parfitt L.J., Scollan N.D., Minchin F.R. (2007): Lipolysis in red clover with different polyphenol oxidase activities in the presence and absence of rumen fluid. J. Sci. Food Agric. 87:1308 1314  Steinshamn H., Purup S., Thuen E., Hansen Moller,J. (2008): Effects of clover grass silages and concentrate supplementation on the content of phytoestrogens in dairy cow milk. J. Dairy Sci. 91. Article in press. doi:10.3168/jds.2007 0857. Steinshamn H., Thuen, E. (2008): White or red clover grass silage in organic dairy milk production: Grassland productivity and milk production responses with different levels of concentrate. Livest. Sci. Article in press. doi:10.1016/j.livsci.2008.04.004. Sullivan M. L., Hatfield, R.D. (2006). Polyphenol xxidase and o diphenols inhibit postharvest proteolysis in red clover and alfalfa. Crop Sci. 46:662 670. Thomas C., Aston K., S. R. Daley, S.R. (1985): Milk production from silage 3. A comparison of red clover with grass silage. Anim. Prod. 41:23 31. Thomas C., Gibbs B.G., Tayler J.C. (1981). Beef production from silage 2. The performance of beef cattle given silages of either perennial rye grass Lolium perenne cultivars S 24 or red clover Trifolium pratense cultivar Hungaropoly. Anim. Prod. 32:149 154. van Dorland H. A., Wettstein H.R., Leuenberger H., Kreuzer M. (2006): Comparison of fresh and ensiled white and red clover added to ryegrass on energy and protein utilization of lactating cows. Anim. Sci. 82:691 700. van Dorland H. A., Kreuzer M., Leuenberger H., Wettstein H.R. (2008): Comparative potential of white and red clover to modify the milk fatty acid profile of cows fed ryegrass based diets from zero grazing and silage systems. J Sci. Food Agric. 88:77 85. Vanhatalo A., Gaddnas T., Heikkila T. (2006): Microbial protein synthesis, digestion and lactation responses of cows to grass or grass red clover silage diet supplemented with barley or oats. Agric. Food Sci. 15:252 267. Vanhatalo A., Kuoppala K., Toivonen V., Shingfield K.J. (2007): Effects of forage species and stage of maturity on bovine milk fatty acid composition. Eur. J. Lipid Sci. Techn. 109:856 867.   

The unique properties of red clover in the diet of ruminants

Abstract

Similar works

Full text

Available Versions

Organic Eprints