Updated research, supported by the U.S. Poultry & Egg Association (USPOULTRY) and the U.S. Food and Drug Administration (FDA), has been released quantifying the U.S. poultry industry’s on-farm antibiotic use.
The updated report shows continued improved antibiotic stewardship and commitment to disease prevention within poultry production. As part of its commitment to a transparent and sustainable food supply, the poultry industry works to balance the responsible use of antibiotics considered “medically important” to human health with the need to maintain healthy poultry flocks.
“For many years, USPOULTRY’s board of directors has invested in this research, demonstrating the industry’s sustained commitment to science-based stewardship and the responsible use of antibiotics in poultry production. We value the continued engagement of our members and the numerous poultry organizations that have supported this study, whose long-term participation has enabled robust data collection and a deeper understanding of antimicrobial use patterns across the sector,” said Nath Morris, president of USPOULTRY.
Under the research direction of Dr. Randall Singer, DVM, Ph.D., of Mindwalk Consulting Group LLC and the University of Minnesota, this report represents a 12-year set of data collected from 2013 to 2024 for U.S. broiler chickens and turkeys and represents a nine-year set of data collected from 2016 to 2024 for layers. A prior report, covering 2013-23, was released in December 2024. In addition, three peer-reviewed manuscripts were published by Singer in 2023 covering the data collected from broiler chickens, turkeys and layers. Data can be viewed and downloaded on the Mindwalk Consulting Group website.
Given several key differences among broiler chickens, turkeys and layers – namely differences in weight, life span, susceptibility to lifetime illness, the number of effective medical treatments available, etc. – these data should neither be combined nor compared between types of poultry.
Key changes among broiler chickens over the 2013-24 period:
- Broiler chickens receiving antibiotics in the hatchery decreased from 90% (2013) to less than 1% (2024)
- Medically important in-feed antibiotic use in broiler chickens decreased substantially; there has been no in-feed tetracycline use since 2019, and virginiamycin use has decreased more than 99% over the 12-year period
- Medically important water-soluble antibiotic use in broiler chickens decreased substantially from 2013-17 and has increased slightly from 2017-24. Increases were typically due to increased disease incidence, as seen in other countries as well, during the 2019-24 period. For example, avian metapneumovirus has caused severe morbidity and mortality in some broiler flocks. Infection with this virus can lead to an increased incidence of secondary bacterial infections. Tetracycline antimicrobials have been used to treat and control these secondary infections but with limited efficacy:
- Penicillin use decreased by 64% from 2013-19 but has increased 27% from 2019-24 due to increases in gangrenous dermatitis incidence; overall, penicillin use decreased 53% from 2013-24
- Lincomycin use decreased by 66% from 2013-20 but has increased 15% from 2020-24 due to increases in gangrenous dermatitis incidence; overall, lincomycin use decreased 71% from 2013-24
- Tetracycline use decreased by 66% since 2013
- Sulfonamide use decreased by 81% since 2013
Key changes among turkeys over the 2013-24 period:
- Turkeys receiving antibiotics in the hatchery decreased from 97% (2013) to approximately 45% (2024)
- With recent challenges linked to E. coli and other Gram-negative bacteria in the young turkey poults, gentamicin use in the hatchery increased to help prevent these infections
- Hatchery gentamicin use decreased approximately 40% from 2013 to 2024.
- Medically important in-feed antibiotic use in turkeys decreased substantially; in-feed tetracycline use decreased by more than 77% from 2013-22 but has increased more than threefold since 2022 due predominantly to control and treatment of secondary bacterial infections following infection with avian metapneumovirus.
- Medically important water-soluble antibiotic use in turkeys decreased substantially from 2013-19 and then stabilized or increased from 2019-24. Increases were typically due to increased disease incidence, as seen in other countries as well, during the 2019-24 period. Avian metapneumovirus has caused severe morbidity and mortality in turkey flocks. Infection with this virus can lead to an increased incidence of secondary bacterial infections. Water-soluble tetracycline antimicrobials have been used to treat and control these secondary infections but with limited efficacy:
- Penicillin use decreased by almost 50% since 2013
- Lincomycin use decreased by 58% from 2013 to 2019 but then increased substantially from 2020-24 due to increases in gangrenous dermatitis incidence and a shortage of penicillin
- Neomycin use decreased by 67% since 2013
- Tetracycline use decreased 21% from 2013-22 but then increased from 2022-24, largely due to increases in colibacillosis and secondary infections following avian metapneumovirus exposure
Key findings among layer chickens over the 2016-24 period:
- Layer chickens (hens) typically begin laying eggs around 20 weeks of age and end when the layer hen is around 80 to 100 weeks of age.
- Table egg production is similar to milk production, where the product for human consumption is produced on a daily basis. Most antibiotics that could be administered to layer hens have withdrawal periods that would prevent all eggs produced during this period from entering the food supply. This is one reason why little antibiotic is used in table egg production in the U.S.
- All chicks in the dataset received gentamicin in the hatchery (day 1 of age).
- In the U.S., the majority of chicks purchased by egg companies are sourced from hatcheries that are owned and operated by genetics companies
- The primary medically important antibiotic used in layer hens for treatment and control of disease in this dataset was chlortetracycline (CTC), used in part because it has a zero-day withdrawal when used in-feed, meaning that there is no loss of eggs during the treatment period.
- CTC was only administered via the feed in pullets (day 2 through 16 to 18 weeks of age) and layer hens
- The majority (>95%) of CTC was used in the layer hens for treatment of disease. No pullets in the dataset were given CTC in the feed during 2022 or 2023, and a minimal amount was used in pullets in 2024
- Less than 0.1% of total hen-days were exposed to CTC
USPOULTRY will continue to support Singer in the annual collection of data from the broiler chicken, turkey and layer industries. These efforts will assist the poultry industry as it aims to improve antibiotic stewardship and will also document the burden of flock illness and reasons for on-farm, medically important antibiotic usage.
This project is funded with multiple annual grants from USPOULTRY. The project was also partly supported from 2016 to 2023 under a cooperative agreement with the USDA (U01FD005878). Beginning in September 2024, a new cooperative agreement between FDA-CVM and Singer was initiated, thus continuing the public-private partnership for this effort.
