A Review of Probiotic Applications in Poultry: Improving Immunity and Having Beneficial Effects on Production and Health

A new class of feed additives and nutritional supplements, known as probiotics, include bacterial, fungal, and yeast cultures from various sources. Overall, probiotics are believed to promote the health and well-being of animals, birds, and humans in a variety of settings. Incorporating probiotics into the diets of cattle and poultry has been demonstrated to improve growth, feed conversion efficiency, immunological responses, and the animal's ability to manage enteric infections. The use of probiotic-enriched chicken feed has been shown to enhance egg production by as much as 30% among laying chickens. Probiotics may be used to fight off harmful microorganisms, create antibacterial compounds (such as bacteriocins or colicins), and alter the immunological response of the host, according to the National Institutes of Health. Pathogenic microbial strains such as Lactobacillus, Streptococcus, Bacillus, Enterococcus, Pediococcus, Aspergillus, and Saccharomyces are employed in the making of chicken products. The use of subtherapeutic doses of antimicrobial agents, including antibiotics, to combat or remove harmful bacteria and promote animal growth and feed efficiency has resulted in the accumulation of antibiotic residues in animal feed as well as the emergence of drug-resistant microbes in the feed supply chain. As a result of public health concerns, there has been a renewed emphasis on the use of probiotics in chicken production rather than antibiotics in recent years. This research examines the effects of probiotics and direct-fed microorganisms (DFM) on chicken health and performance, with a particular emphasis on the favourable effects they have on poultry health and performance.