Growth stage and ensiling: impact on chemical composition, conservation quality and in situ ruminal degradability of whole‐crop oat

Abstract

BACKGROUND The effects of growth stage (GS) and ensiling were assessed on whole‐crop oat's (Avena sativa L. cv. Cantara) chemical composition, silage fermentation quality and in situ ruminal degradability. Oat was harvested and ensiled at six GS: boot, heading, water ripe, early milk, early dough and grain ripe (144, 151, 178, 234, 362 and 512 g kg−1 of dry matter (DM) of whole‐crop forage, respectively). RESULTS GS influenced chemical composition, silage fermentation quality and ruminal degradability of whole‐crop oat. Lower DM and higher water‐soluble carbohydrates (WSC) contents lead to adequate forage compaction and fermentation at early GS; however, effluent was produced until the dough stage (L and Q; P ≤ 0.003). Advancing in maturity increased (P < 0.001) crop yield (4.5 to 9.4 t DM ha−1), DM (144 to 512 g kg−1), neutral detergent fibre (NDF; 537 to 571 g kg−1 DM), lignin (44.6 to 71.3 g kg−1 DM) and starch contents (26.4 to 201 g kg−1 DM), and reduced (P < 0.001) crude protein (107 to 60 g kg−1 DM) and WSC (115 to 17.5 g kg−1 DM). DM and NDF ruminal degradability declined with maturity for fresh and ensiled forages (L and Q; P < 0.05). Density and buffering capacity decreased with GS (L and Q; P < 0.001), whereas pH and soluble protein increased (L and Q; P ≤ 0.004). CONCLUSION The growth stage of oat influenced the nutritive value and ruminal degradation to a greater extent than ensiling, and thus it can play a paramount role in whole‐crop oat silage quality. © 2021 Society of Chemical Industry.

The Effect of Early and Delayed Harvest on Dynamics of Fermentation Profile, Chemical Composition, and Bacterial Community of King Grass Silage

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Assessing the impact of phyllosphere microbiota on dynamics of in‐silo fermentation of Italian ryegrass harvested at heading and blooming stages

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Effects of tillage and maturity stage on the yield, nutritive composition, and silage fermentation quality of whole-crop wheat

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