Evaluating the effects of supplementing Saccharomyces cerevisiae in the feed or drinking water on stress susceptibility of broilers

Abstract

Poultry are susceptible to stress as a response to a multitude of environmental stressors such as handling, vaccination, feed outages, rearing on used litter, and elevated ambient temperature. Birds subjected to environmental stressors can experience loss of appetite, lethargy, reduced body weight gain, loss of feed efficiency, and increased mortality. These stressors can trigger the stress response, impair immunity, and introduce foreign pathogens. When a bird becomes stressed, a cascade of hormonal events can occur, ultimately resulting in the production and release of corticosterone. As the primary stress hormone, corticosterone regulates the immune response and shifts metabolic processes to increase readily available energy, thereby impacting normal growth and production. Reducing environmental stressors is an important goal in broiler production. It is essential to mitigate stress to minimize morbidity and improve both growth performance and animal welfare. Feed additives such as yeast fermentation products may be effective in reducing stress associated factors and may improve bird performance.