Addressing Salmonella incidence in humans through poultry feed additives

Mar 21 2019

The Centers for Disease Control and Prevention estimated that Salmonella causes 1.2 million cases of bacterial foodborne illness each year and approximately 450 deaths. It is estimated that 30 percent of Salmonella cases are contracted due to poultry. To effectively reduce the number of Salmonella infections, attention must be focused on poultry’s role in transmitting the disease.

In the United States, the Department of Health and Human Services (HHS) has set a goal to reduce the total Salmonella incidence by 7.49 percent by the year 2020. Because Salmonella is commonly introduced into poultry production through poultry feed, our goal is to provide information about feasible methods to reduce Salmonella presence in poultry feed and thus in poultry.

Research Question: Can the introduction of probiotics or essential oils in poultry feed facilitate the CDC’s objective to reduce Salmonella incidence in humans?

Background Information: Antimicrobial drugs have been widely used in human and veterinary medicine for more than 50 years, resulting in tremendous benefits to both human and animal health.

Antibiotics, probiotics, and essential oils all act as antimicrobials and can be used as feed additives.

Antibiotics are the most widely used antimicrobial in the poultry industry. Since the 1950s, antibiotics have been used for harvesting, growth promotion, and disease prevention. Despite these benefits, antibiotics can cause bacteria to become multi-drug resistant, leading to possibly untreatable cases of Salmonella in humans.

Probiotics are live organisms that are used to alter and enhance metabolic activities and aid immune system reactivity in a manner that benefits health. The use of probiotics in chicken feed can combat the colonization of multidrug-resistant Salmonella because the probiotics improve gut microflora, limiting Salmonella proliferation. We found the Lactobacillus-based probiotic to be the most widely used probiotic to counteract the effects of Salmonella. In addition to reducing Salmonella incidence,


Lactobacillus contributes to flock uniformity, a lowered mortality rate, protective gut microflora, daily weight gain increases, and improved feed conversion. Essential oils are aromatic plant extracts that penetrate the bacterial cell wall and disrupt the normal physiology of certain types of p-H sensitive bacteria, such as Salmonella. Oregano oil is a type of essential oil that has shown to decrease Salmonella incidence in broilers.


This report serves as a toolbox that the CDC can use to approach the poultry industry. Using the HHS’s reduction goals, we provide recommendations for the percentage of feed conversion as well as a framework for various scenarios of market penetration necessary to achieve these goals.

Furthermore, this report demonstrates the economic impact of implementation on the industry by estimating how the introduction of antimicrobials will affect their bottom line. Based on our analysis, we recommend that the poultry industry implement probiotics as a feed additive. The CDC can use the information provided to inform the industry of the potential benefits of probiotics and essential oils.