Clover, grazing

OBST J M, SEAMARK R F (1975) Hormone Studies on Ewes Grazing an Oestrogenic (Yarloop Clover) Pasture During the Reproductive Cycle. Aust J Biol Sci. 28 279-90. 

The upland organic farm in the hills of Wales was cited earlier in connection with white clover. Here the problem of clean grazing is more intractable, first because there are no cattle and second because none of the land is suited to cereals. The best approach, suggested in... 

Niezen, J., Ha., R., Sidey, A. and Wilson, S. (2002a). The effect of pasture species on parasitism and performance of lambs grazing one of three grass - white clover pasture swards . Veterinary Parasitology, 105, 303-215. 

In the mid-1940s it was reported that ewes grazing on subterranean clover in western Australia become sterile (Bennetts et ah, 1946). This effect has not been observed for other species being fed isoflavones and or in humans on high-soy diets (Munro et ah, 2003). 

In Australia, lambing in sheep has dropped to as little as 30% after grazing on subterranean clover. Trifolium subterraneum. The clover contains the isoflavonoids formononetin and genistein (Fig. 11.11). These compounds mimic the steroidal nucleus of the natural female hormone estrone. Alfalfa, M. sativa, and ladino clover. Trifolium repens, contain the even more potent isoflavonoid coumestrol. It is 30 times more active than genistein or formononetin, but occurs in lower concentrations in the plant (Shutt, 1976). 

Coumestans, such as coumestrol, are found in high concentrations in alfalfa and clover and have been recognized, along with formononetin, as the cause of infertility in grazing herbivores. Whereas coumestrol acts as an estrogen mimic directly, formononetin has to be metabolized to the estrogenically active compounds diadzein, equol, or >-demethylangolensein. 

Other studies have shown that a strain of Butyrivibrio hungatei isolated from a cow grazing ryegrass-clover swards is capable of metabolizing both... 

BOIA A Vitamin K antagonist This group comprises vitamin K antagonists such as the dicoumarol group. The plant Melilotus officinalis (L.) Pallas, family Fabaceae, that has become mouldy due to microorganisms, caused disease in grazing cows, Sweet Clover Disease , where the cows died ftom internal bleeding. The discovery that this disease was... 

Roy (1979) Rye grass and clover Not given 0.17-9.6 Field grazed by sheep... 

The residual effects of Mo fertilizers are related to the reactions of the applied Mo with the soil. Mo removal by cropping and by grazing animals, and the extent of Mo leaching from the root zone. One of the earliest reports of marked residual effects from applied Mo was by Anderson (1956). Growth effects due to Mo application at 70gha to subterranean clover Trifolum subterraneum L.) pastures were still evident after 10 years. 

Shand et al. (1994) Soii soiution (centrifugation) Brown forest soils Scotland Upland grazed grass/clover 0-18 55-110 85-96... 

Four different grass/clover management systems are compared (G = grazing, CG 1= one silage cut -I-aftermath, CG 2 = two silage cuts -i- aftermath, CO = cutting only, with four cuts per year). 

Horrill, j. C. and A. J. Richards, Differential grazing by the mollusc Arion hortensis Fer. on cyanogenic and acyanogenic seedlings of the white clover. Trifolium repens L., Heredity, 56, 277-281 (1986). 

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