The growth and development of ruminants are closely linked to the stability and functional capacity of their rumen microbiota. Rumen microbiota transplantation (RMT), which entails the transfer of ruminal microorganisms and their metabolites from healthy donors to recipient animals, has emerged as a promising strategy for modulating host physiology. Accumulating evidence indicates that RMT can substantially influence nutrient digestion, immune function, and overall growth performance. This review synthesizes current knowledge on the mechanisms through which RMT affects ruminant growth and development, with particular attention to its roles in shaping microbial colonization and succession, enhancing rumen fermentation efficiency, and modulating host metabolic pathways. Together, these regulatory processes contribute to improved rumen maturation in young animals and enhanced production performance in adults. In addition, this review critically examines key factors governing the efficacy of RMT, including transplantation procedures, donor microbiota characteristics, and the physiological status of recipient animals. By integrating these insights, the present synthesis provides a conceptual framework to support the precise and effective application of RMT in the sustainable management of healthy ruminant production systems.