Mixtures of Forage Species as Pasture for Dairy Ewes in a Mediterranean Environment

Abstract

In Sicilian forage systems, the introduction of native self-seeding annual legumes can be beneficial in low-input farming. Intercropping would be a valuable strategy for implementing pasture resources in Sicilian forage systems during late spring. The aim of this study was to evaluate the effects on ewes' milk production of continuous grazing with two different mixtures (i) sulla (Sulla coronarium L.), burr medic (Medicago polymorpha L.), and chicory (Cichorium intybus L.) (SuBuCh); and (ii) barrel medic (Medicago truncatula Gaertn.), snail medic (Medicago scutellata L.), and burr medic (BuSnBa). Twenty lactating ewes were homogeneously divided into four groups of five ewes. Each group was assigned to one of four 1500 m2 grazing sectors consisting of two replicates of SuBuCh and BuSnBa. Ewes fed with the SuBuCh mixture showed higher milk yield, higher protein (5.17 vs. 4.85%, p < 0.001) and casein content (4.02 vs. 3.73%, p < 0.001), lower urea content (37.70 vs. 45.38 mg dL-1, p < 0.001), and better clotting parameters compared to ewes grazing on the BuSnBa mixture. Finally, ewes in the SuBuCh group showed a smaller decrease in live weight at the end of the grazing period compared to BuSnBa ewes (-2.05 vs. -3.55 kg, respectively), although the difference did not reach a significant level. These preliminary one-year results seem to highlight the promising role of SuBuCh intercrop leading to a potential quantitative/qualitative improvement in grazing resources and the productive performance of grazing ewes in a semi-arid Mediterranean environment. However, it is of note that these outcomes might undergo variations when subjected to a prolonged trial extending beyond three years.