Effects of fermentation duration on nutritional value, probiotic components and growth performance in beef cattle fed fermented Chinese medicine residue

Chinese herb residues, byproducts of extracting active ingredients from herbs, are often underutilized due to their high fiber content and strong flavor. However, they have significant potential as a sustainable feed resource. Fermentation has been shown to enhance their nutritional value and palatability, but the optimal fermentation duration to maximize these benefits remains unclear. This research examined the effects of fermentation durations of 3, 6, 9, and 12 days on the nutrient composition and probiotic content of the fermented Chinese herb residues (FCHRs). Results showed that a 3-day fermentation period significantly improved the nutritional value and probiotic components of the residues, with higher DM, reducing sugar, and butyric acid contents (P < 0.05). The NDF content was highest in the 6-day fermentation group, while the ADF contents were highest in the 9-day and 12-day groups (P < 0.05). The viable bacteria count was also highest in the 3-day fermentation group. When fed to beef cattle, the fermented residues did not negatively impact growth performance, and showed potential for reducing feed costs and waste.This study is the first to optimize fermentation duration for pharyngitis tablet residues, providing valuable insights into optimizing fermentation processes for utilizing Chinese herb residues as a high-quality feed resource.