Process Optimization of Compound Fermented Traditional Chinese Medicine and Its Feeding Effect on Dairy Cows

This study evaluated the efficacy of a compound fermented traditional Chinese medicine (TCM) preparation in dairy cows. Five TCMs and three probiotics were selected from 25 candidate herbs and six probiotics based on in vitro antibacterial activity against Staphylococcus aureus and Escherichia coli using agar well diffusion and paper disc diffusion methods. The five TCMs were formulated according to the “Jun-Chen-Zuo-Shi” principle, and the optimal solid-state fermentation process was identified through single-factor and orthogonal experiments. The results showed that the optimal conditions included a Bacillus subtilis : Bacillus coagulans : Lactobacillus plantarum ratio of 1:3:1, a moisture content of 32%, an inoculation rate of 10%, a temperature of 31°C, and a fermentation period of 5 d. HPLC was used to examine changes in bioactive compound levels before and after fermentation. Fermentation significantly increased the concentrations of Resveratrol , Polydatin , and Quercetin , whereas the Polydatin content decreased. To determine in vivo effects, the fermented TCM was fed to dairy cows, and the indices of production performance, milk quality, serum biochemical levels, immune function, antioxidant capacity, and hormone levels were evaluated, and the changes in intestinal flora were analyzed by sequencing rectal contents using the 16S rRNA. The results showed that fermentation TCM signiffcantly improved the production performance of dairy cows as well as the milk quality, enhanced humoral immunity, strengthened antioxidant capacity, favorable modulation of gut microbiota, and metabolic regulation. This study provides strong experimental support for developing and applying compound fermented TCMs as functional feed additives in dairy production.