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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., (© 2021 Society of Chemical Industry.)

Background: This work aimed to study the chemical composition and in vitro digestibility of seeds and pulp from grape pomace. In sacco degradability, ruminal fermentation of grape pomace fractions and plasma lipid peroxidation were also studied in sheep fed with or without grape pomace., Results: Seed and pulp fractions of grape pomace had different values for cell walls (523 vs 243 g kg -1 dry matter (DM)), crude protein (CP, 104 vs 138 g kg -1 DM), ether extract (EE, 99.0 vs 31.7 g kg -1 DM), polyunsaturated fatty acids (PUFA, 69.6 vs 53.3%) and extractable polyphenols (55.0 vs 32.1 g kg -1 DM). The in vitro true digestibility, DM in sacco degradability and CP degradability of seeds and pulp were also different (0.51 vs 0.82, 0.30 vs 0.45 and 0.66 vs 0.39 respectively). The ammonia-N concentration and total volatile fatty acids (VFA) in ruminal liquid were significantly lower and plasma lipid peroxidation was also numerically lower in sheep that consumed grape pomace., Conclusion: The nutritive value of grape pomace varies depending on the proportion of seeds and pulp. The interest of this by-product in sheep feeding could be related to its polyphenol and PUFA content, which could improve meat and milk quality. © 2016 Society of Chemical Industry., (© 2016 Society of Chemical Industry.)