Triticale and mixtures silages for feeding dairy cows
Résumé
In areas where the conservation of water resources is becoming of strategic importance, farmers and advisers are requiring silages made without irrigation and pesticides. We evaluated in this study the agronomic and zootechnical performances of winter crops harvested as silage in spring. To determine the effects of the presence of legumes (simple or complex mixture) compared to pure cereals, three crops were compared: a pure triticale (Triticosecale W.) crop (T1), a triticale and forage pea (Lathyrus sativus L.) mixture (T2), and a complex mixture of triticale, pea, oat (Avena sativa X.) and vetch (Vicia sativa L.) (T3). The crop trials were conducted in large fields (2 ha each), on a low-input management basis (no pesticides, mineral nitrogen provided only to T1 treatment). The three silages were offered ad libitum to 24 mid-lactation dairy cows in a replicated 3×3 Latin square design. Periods were 3 weeks long. Intake and animal performances were measured. The forages yielded 8.9, 8.1 and 7.4 t DM ha-1 respectively for T1, T2 and T3 treatments. The effect of treatment on forage intake and milk production were significant. Daily intake were 9.0 kg, 10.1, 10.9 and milk production were 19.6 kg, 20.6, 21.4 respectively for T1, T2 and T3. Cereal and mixtures silages, harvested before the summer drought should provide useful forage without needing irrigation.