Biotechnological approaches in farm animals’ nutrition have a profound influence on animal health, growth performance, production, and reproductive outcomes. The use of probiotics has substantially mitigated numerous challenges that are endemic to global livestock production. The rising demand for productivity enhancement, optimal animal health, and consumer apprehensions regarding food safety concerns, particularly rising from the indiscriminate use of antibiotics, have induced a pivotal transition towards safer alternatives, notably probiotics. In response to the expanded adoption of probiotics in animal nutrition, this chapter elaborates the impact of probiotics on animal health, growth and production performance. Several advantages have been reported with the incorporation of probiotics in farm animals, such as accelerated growth and increased product quality. Probiotics used as feed additives in ruminant rations typically modulate the intestinal microbiota, ameliorate the rumen microflora of calves and adults, enhance digestion and optimize nitrogen flux towards the lower digestive tract, and augment meat and milk yield. This chapter systematically discusses the effects of various probiotics on different animals. Additionally, the prevalent types of probiotic products, their functional characteristics, and their application effects are discussed to provide a comprehensive reference for the improvement and implementation of probiotic products.