Vol. 9, Special Issue 1 (2024)

Author(s): P Das and MS Meel

Abstract: Ruminant nutritionists and microbiologists have been regulating the rumen microbial ecology for over 30 years in order to improve production efficiency and reduce productivity loss due to rumen acidosis. Direct-fed microbials (DFM) are a safe alternative to antibiotics for improving animal performance. Direct-fed microbials (DFM) are a safe alternative to antibiotics for improving animal performance. DFM was largely utilized in young ruminants to promote gut health and establish the intestinal microbiota involved in feed digestion. Host receives protein, vitamins, and short-chain organic acids from beneficial microorganisms. Treatment with DFM increases anti-pathogenic effects and reduces Animal stress. It is common practice in DFM for rumen to use lactic acid producing, utilising bacteria or other microorganism species like Lactobacillus, Bifidobacterium, Enterococcus, Bacillus, Propionibacterium, Megasphaera elsdenii, and Prevotella bryantii, along with some yeast species like Saccharomyces and Aspergillus. By altering the rumen environment, bacterial DFM has the potential to encourage weight increase and feed efficiency. Fungal DFM aids in the reduction of toxic oxygen in the rumen, the prevention of excessive lactate generation, the improvement of feed digestibility, and the improvement of rumen fermentation patterns. Dry matter intake, milk yield, fat corrected milk yield, and milk fat content may all benefit from DFM. However, the response to DFM differs depending on DFM strains, doses, and feeding times and frequencies. Therefore, the goal of this review study is to overview of the mechanism of action and pros and cons of feeding DFM on many aspects of rumen health and production in cows.