The aim of this work was to study the yield and nutritional characteristics of winter wheat hay. A selection of cultivars recommended for three main purposes: grain, whole plant (biomass) and dual purpose (grain and biomass) production were cultivated and harvested from heading to grain dough stages. Yield dry weight (YDW), dry matter (DM) and undigested neutral detergent fiber (uNDF) increased with advancing maturity, ranging from 9 t ha⁻¹, 20 and 11% of DM to 16 t ha⁻¹, 43 and 17% of DM, respectively; while crude protein (CP) and neutral detergent fiber (NDF) decreased from 11 and 59% of DM to 6 and 54% of DM, respectively. Our study showed that dual purpose winter wheat cultivars displayed similar performance of CP, NDF and net energy for lactation, when harvested at heading or grain milk stages. In addition, winter wheat recommended to be harvested as whole plant showed similar values of YDW, sugar and starch contents, when harvested at grain dough and milk stages. These characteristics are strategic in hay production, allowing a more flexible harvesting strategy. These results might be useful to improve the hay production, given useful information on harvest time and improving agricultural sustainability covering the soil in autumn and winter.

中文翻译：

---

收获时间对意大利北部冬小麦干草产量和品质的影响

这项工作的目的是研究冬小麦干草的产量和营养特性。推荐了三个主要目的的栽培品种：谷物，全株（生物质）和双重用途（谷物和生物质）生产，从抽穗期到谷物面团阶段进行收获。随着成熟度的提高，干重（YDW），干物质（DM）和未消化的中性洗涤剂纤维（uNDF）的增加范围从DM的9 t ha ^-1，DM的20％和11％到16 t ha ^-1，DM的43％和17％；而粗蛋白（CP）和中性清洁剂纤维（NDF）分别从DM的11％和59％降至DM的6％和54％。我们的研究表明，在抽穗期或谷物乳阶段收获的两用冬小麦品种表现出相似的CP，NDF和净泌乳能量。此外，建议在整个谷物中收获的冬小麦，在谷物面团和牛奶阶段收获时，其YDW，糖和淀粉含量具有相似的值。这些特征在干草生产中具有战略意义，因此可以采用更灵活的收获策略。如果提供有关收获时间的有用信息，并改善秋冬季覆盖土壤的农业可持续性，这些结果可能对提高干草产量很有帮助。