Sward Height Effects on Sward Composition and Animal Performance in Grass/Clover Swards Co-Grazed by Sheep and Goats

A mixed herd of yearling cashmere bucks plus Gallega and Lacha ewes rearing single lambs continuously grazed lowland perennial ryegrass (Lolium perenne) / white clover (Trifolium repens) swards on two contrasting sward surface heights of 8.3 (High) or 5.9 cm (Low) over a 100-day spring grazing period. Performance results showed that ewes and bucks had respectively an extra 2.6 and 2.0 kg of liveweight gain in the High height treatment while lambs replenished 185 (High) and 198 (Low) g of daily liveweight. Significant increases of live clover occurred in both sward height treatments and that was especially more marked in the surface layers (P<0.001) where dead and ryegrass stems appeared in fewer proportions than in the bottom horizons. It is concluded that yearling bucks, independently of their physiological state, can fit well under simultaneously grazing with ewes and lambs on grass/clover swards maintained within the 9 - 6 cm height range to benefit sheep performances, clover enhancements and sward reproductive and senescent deferments.