In many parts of Europe there has been a net decline in the use of forage legumes since the 1980s, despite the reputed value of legumes for low-input livestock production systems. The political environment within which livestock farming in much of Europe operates (Common Agricultural Policy) is shifting the balance of economic advantage towards legumes and away from high usage of inorganic fertilizer. This has already been found for legume and grass-legume silages when compared with grass silages with a potential economic gain for farmers averaging 137 ha )1 , corresponding to an annual benefit for the European livestock farming sector of as much as 1300 million. Recent literature has shown that legume-based grazing systems have the ability to reduce environmental problems by increasing the efficiency of N use and by avoiding a high transient surplus of soil mineral N. From the perspective of livestock nutrition, when forage legumes contain moderate levels of secondary compounds, such as condensed tannins and flavonoids, they offer considerable advantages including increased efficiency of N utilization within the digestive tract, reduced incidence of bloat hazard and higher resilience to parasites.Nevertheless, these benefits are partially counterbalanced in both temperate and Mediterranean regions by difficulties in establishment, maintenance and management under grazing. To gain knowledge on mixed grass-legume pastures, further research is required on: (i) the development of sustainable systems of livestock production which can maintain sward persistence and agricultural production under environmental stress; (ii) increasing knowledge of soil-plant-animal relations for a wide range of leguminous species, and under different soil types and climatic situations; and (iii) the benefits for consumers of food produced from low-input livestock production systems.

Intake and performance of sheep or cattle grazing legume-based swards were assessed over 2 years at four locations in Europe with different climatic conditions: Sardinia (Italy), southern France, northern Germany and south-west England (UK). Legume species were sown in mixtures with locally appropriate companion grass species. Standard legume species commonly used at the location (Medicago polymorpha in Italy, Medicago sativa in France, and Trifolium repens in Germany and UK) were compared with two alternative legume species characterized by different agronomic or nutritional characteristics. They were: Trifolium subterraneum and Hedysarum coronarium in Italy; Trifolium incarnatum and Onobrychis sativa in France; Trifolium pratense and Lotus corniculatus in Germany; and Trifolium ambiguum and L. corniculatus in the UK. Lactating milk sheep in Italy, non-lactating ewes in southern France, growing cattle in Germany, and ewes and lambs in the UK were used in three replicates per treatment. Intake and performance of sheep and cattle in various treatments varied with location, year and period within year. In Germany, intake and performance by cattle were not affected by treatment. In contrast, at the other locations, sheep grazing standard or alternative legume species known to contain condensed tannins (sulla, sainfoin and birdsfoot trefoil) had higher proportions of legume and crude protein (CP) concentrations in the diet and higher CP intakes than those grazing the other alternative legume species. Sheep performance paralleled these results. It is concluded that there is potential for a greater use of alternative legume species, at least for sheep-grazing systems, in both the Mediterranean and cool temperate zones of Europe.

This study reports the leaching of nitrogen (N), phosphorus (P) and potassium (K) from beneath grazed leguminous swards established at two Mediterranean and two north-western European sites. The purpose of the experiment was to provide scientific evidence on whether moderately extensive systems of animal production based on legumes could be environmentally sustainable, to comply with the Water Framework Directive. There were differences in the legume species and the grazing animal between sites, reflecting differences in local management and climatic conditions. There were also differences in the methods used to assess nutrient leaching, again reflecting soil and hydrological conditions present. There were no general differences between the quantities of nutrient leached at Mediterranean and north European sites over the 3 year experiment and these quantities, up to 6 kg ha )1 year )1 for nitrate-N, were similar to those reported from earlier studies of leaching beneath grasswhite clover swards at temperate sites. Temporal variability in leached nutrient concentrations and amounts was greater at the Mediterranean sites. There were no discernible differences in the effects of sward treatment on leaching. The proportion of N leached in organic combination or as ammonium was greater than with N-fertilized grass systems. The quantities of P leached were relatively high, ranging from 0AE1 to 3 kg ha )1 year )1 for soluble reactive P, reflecting the practice of high levels of fertilizer application to these systems. Reduction of P transfer to water from these systems will be critical for future compliance with the Water Framework Directive.

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