Abstract

The study was conducted with the objective of evaluating the nutrient content, fermentation characteristics, microbial counts, and ruminal degradability of two mixtures of Italian ryegrass (Lolium multiflorum Lam.) and winter cereal silages. Two mixtures (mixture A: Italian ryegrass, triticale, oats, wheat and barley; and mixture B: Italian ryegrass and oats) were wilted and ensiled in laboratory‐scale silos without additives. At the end of 90 d fermentation mixture B silage had higher (p < .05) dry matter (DM), ether extract (EE), crude fibre (CF), neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents than mixture A silage. The pH value of mixture B was higher (p < .05) than mixture A silage. Mixture A had higher lactate, acetate and ethanol contents than mixture B. However, mixture B had higher NH₃-N (day 14) than mixture A silage. The mould and yeast count (Log₁₀ CFU g⁻¹) was higher (p < .05) for mixture A than mixture B at opening day 7. The in situ incubation revealed that potentially degradable fraction (b) of DM, CP and NDF was 39.41%, 43.59%, 80.23% (mixture A) and 39.16%, 32.39%, 94.35% (mixture B). The effective protein degradability (EPD) at 0.08 rumen outflow rates was 67.26% (mixture A) and 67.19% (mixture B). These results suggest that with the proper stage of harvesting, Italian ryegrass and winter cereal mixtures were fermented well. This kind of mixtures can be ensiled without additives in the future. The high potentially degradable NDF and effective protein degradability implies that this mixture could be included successfully in high-yielding dairy cattle diets.

• Highlights

• Italian ryegrass and winter cereal mixtures are well preserved without additives and it saves the cost of additives for dairy farmers.

• The ensiled mixtures have high potentially degradable NDF and effective protein degradability, which improve dry matter intake, milk production and increase the net return of farm.

• The mixture forage can be double-cropped with corn for silage making, which can have both environmental and economic benefits if the ensiled mixture yields are enough to cover expenses.

摘要

进行这项研究的目的是评估意大利黑麦草（黑麦草）和冬季谷物青贮饲料的两种混合物的营养成分，发酵特性，微生物数量和瘤胃降解性。将两种混合物（混合物A：意大利黑麦草，小黑麦，燕麦，小麦和大麦；混合物B：意大利黑麦草和燕麦）在没有添加剂的实验室规模的筒仓中进行了青贮和青贮。在90天发酵混合物末期，青贮饲料B的 干物质（DM），乙醚提取物（EE），粗纤维（CF），中性洗涤剂纤维（NDF）和酸性洗涤剂纤维（ADF）含量较高（p <.05）比混合物A青贮。混合物B的pH值较高（p <.05）比混合物A青贮饲料。混合物A具有比混合物B更高的乳酸盐，乙酸盐和乙醇含量。然而，混合物B具有比混合物A青贮饲料更高的NH ₃ -N（第14天）。 在第7天开业时，混合物A的霉菌和酵母菌计数（Log ₁₀ CFU g ^-1）高于混合物B （p <.05）。原位孵育表明，潜在的可降解级分（bDM，CP和NDF的）分别为39.41％，43.59％，80.23％（混合物A）和39.16％，32.39％，94.35％（混合物B）。在瘤胃流出率为0.08时，有效蛋白质降解率（EPD）为67.26％（混合物A）和67.19％（混合物B）。这些结果表明，在适当的收获阶段，意大利黑麦草和冬季谷物混合物发酵良好。将来，这种混合物可以不添加任何添加剂而制成青铜。高潜在降解性NDF和有效的蛋白质降解性意味着该混合物可以成功地包含在高产奶牛日粮中。

• 强调

• 意大利黑麦草和冬季谷物混合物在没有添加剂的情况下保存完好，为乳农节省了添加剂的成本。

• 混合后的混合物具有很高的潜在可降解NDF和有效的蛋白质降解能力，从而改善了干物质的摄入量，牛奶产量并增加了农场的净回报。

• 混合草料可以用玉米双作青贮饲料，如果青贮的混合物的产量足以支付费用，则可以同时具有环境和经济效益。