Simple Summary: Our study elucidated the specific alterations in rumen microbiota associated with subacute ruminal acidosis (SARA) triggered by a high-concentrate diet. It demonstrated that SARA can lead to a decrease in microbial richness and diversity in the rumen of goats. SARA could potentially hinder the growth of rumen bacterial communities. Within the context of SARA, the antioxidant capacity of goats diminishes, while inflammatory cytokines increase, potentially raising the risk of health issues in growing goats. Understanding this is crucial for predicting changes in goat microbiota a...