Objective: This study was conducted to investigate the effects of molasses and Lactobacillus plantarum on the ensiling quality and in vitro rumen fermentation of sudangrass silage prepared with or without wilting.Methods: The ensiling experiment, measured with 3 replicates, was carried out according to a 2×4 (wilted stages×additives) factorial treatment structure. Dry matter of the fresh (210 g/kg fresh matter) or wilted (305 g/kg fresh matter) sudangrass were ensiled (packed into 5.0-L plastic jars) without additive (control) or with molasses (M), Lactobacillus plantarum (LP), or molasses + Lactobacillus plantarum (M+LP). After 60 days of ensiling, the silages were analyzed for the chemical, fermentation, and in vitro characteristics.Results: After 60 days of ensiling, the fermentation parameters were affected by wilted, the additives and the interactions of wilted with the additives (p<0.05). The M+LP treatment at wilted had higher lactic acid levels and V-score (p<0.05) but lower pH values and butyric acid concentrations than the other treatments. In comparison with sudangrass before ensiling, after ensiling had lower dry matter and higher non-fibrous carbohydrate. The in vitro gas production, in vitro dry matter digestibility, in vitro crude protein digestibility, and in vitro acid fiber detergent digestibility changed under the effects of the additives. Significant interactions were observed between wilted and the additives in terms of in vitro gas production at 48 h, asymptotic gas production, gas production rate, half time, and the average gas production rate. The total volatile fatty acid levels in the additive treatments were higher than those in the control.Conclusion: Wilting and supplementation with molasses and Lactobacillus plantarum had the ability to improve the ensiling quality and in vitro nutrient digestibility of sudangrass silage. The M+LP treatment at wilted exhibited the strongest positive effects on silage quality and in vitro ruminal fermentation characteristics.

Grape pomace, a winemaking byproduct, is nutrient- and polyphenol-rich, but research on its use in beef cattle is limited. This study explored the impact of grape pomace-based complete pellet feed on growth, serum biochemistry, fatty acid profile, and rumen microbiota in beef cattle. Fifteen healthy Simmental cattle were randomly divided into three groups (G0, G15, and G20) and fed a complete pelleted ration containing 0%, 15%, and 20% of grape pomace, respectively, for 60 days. The results showed that the addition of grape pomace to the ration markedly increased the average daily feed intake and average daily weight gain in beef cattle. In terms of biochemistry, the levels of total protein (TP) and albumin (ALB) in the G20 group were higher than in the G0 group (p > 0.05). The levels of oleic acid, linoleic acid, and behenic acid were higher in the G20 group than in the G0 group. Grape pomace had no significant effect on rumen fungal diversity and total volatile fatty acids (TVFAs) in beef cattle. The pH and ammonia nitrogen content in the G15 and G20 groups were significantly higher than that in the G0 group. This indicates that grape pomace can be used as feed raw material for beef cattle.