The Recent Trend in the Use of Multistrain Probiotics in Livestock Production: An Overview

SIMPLE SUMMARY: Probiotics are live microorganisms that confer a health benefit to the administered animal when ingested. Their use has been an effective alternative to antimicrobial growth promoters in the livestock industry, and they could be bacteria or non-bacterial species or strains. However, there has been an increasing trend in administering multistrain probiotics in recent years. Multistrain probiotics comprise two or more species or strains of important microorganisms as a consortium beneficial to the administered animal. Several studies are being carried out to explore their potency or efficiency. They have proven to be a promising alternative to antibiotics growth promoters and were responsible for enhancing gut health, growth performance, maintaining a balance in gut microbiota, stimulating immunity against pathogenic organisms, improving digestion, and overall production efficiency in ruminants, poultry, and swine production. ABSTRACT: It has been established that introducing feed additives to livestock, either nutritional or non-nutritional, is beneficial in manipulating the microbial ecosystem to maintain a balance in the gut microbes and thereby improving nutrient utilization, productivity, and health status of animals. Probiotic use has gained popularity in the livestock industry, especially since antimicrobial growth promoter’s use has been restricted due to the challenge of antibiotic resistance in both animals and consumers of animal products. Their usage has been linked to intestinal microbial balance and improved performance in administered animals. Even though monostrain probiotics could be beneficial, multistrain probiotics containing two or more species or strains have gained considerable attention. Combining different strains has presumably achieved several health benefits over single strains due to individual isolates’ addition and positive synergistic adhesion effects on animal health and performance. However, there has been inconsistency in the effects of the probiotic complexes in literature. This review discusses multistrain probiotics, summarizes selected literature on their effects on ruminants, poultry, and swine productivity and the various modes by which they function.