Breadcrumb

1. Home

2. Print 

3. Pdf 

4. Node 

5. Entity Print 

Solutions Through Science: Finding

and Fighting Antimicrobial

Resistance in Animals and the

Environment

Print
A Global Threat: Our Medicines are Becoming Less

Effective

Antimicrobials are substances, such as antibiotics, that kill microorganisms or

prevent them from growing and causing disease. For example, antibiotics are a type

of antimicrobial that fight bacterial infections in humans and animals. Antimicrobial

resistance (AMR) is a global health threat because it makes antimicrobials less

effective. Addressing AMR is a high priority for the agricultural and public health

sectors because antimicrobials are among our most critical tools for treating serious

infections in people and animals. 

What is AMR?

AMR occurs naturally when microbes evolve to survive the drugs designed to

eliminate them. Many things, including medical and veterinary treatments and

disposal of human and animal waste, can affect the number and kinds of resistant
bacteria in people, animals, and the environment.

APHIS’ Role: Teaching Responsible Use

With its extensive animal health expertise and strong Federal, State, and industry

partnerships, APHIS plays a critical role in identifying AMR in diseases found in

livestock and poultry, as well as domestic cats and dogs. To minimize AMR, APHIS

promotes responsible use of antimicrobial products in animals.

Studying On-Farm Practices and Resistance

APHIS’ National Animal Health Monitoring System (NAHMS) collects survey

information provided by U.S. farmers and ranchers. The goal of collecting this

information is to better understand how antimicrobials are used in animal

agriculture. NAHMS looks at representative percentages of operations that use

antimicrobial drugs, the reasons for their use, and the percentage of animals

treated. NAHMS studies also capture data about on-farm antimicrobial stewardship

practices, including recordkeeping, employee training, and the use of veterinarians.

These studies also document tools other than antimicrobials that are used to control

difficult problems, such as liver abscesses in feedlot cattle. The studies give insights

into vaccination and other disease prevention strategies that can decrease the need

for antimicrobials. Recent studies include Health Management on U.S. Feedlots 2021

and Swine 2021.

NAHMS is working with veterinarians, USDA’s Agricultural Research Service, and

several universities on projects to better understand AMR in animals. Some of the

projects focus on improving sampling for AMR in swine and feedlot cattle to promote

better tracking of resistance patterns and antimicrobial use. The projects will also

examine trends in antimicrobial use and AMR on farms where chickens are raised for

meat.

Other projects provide lab testing for goat, swine, and bison fecal samples, which

helps identify AMR in bacteria from these animals and improve our understanding of

the factors associated with AMR. For more information about NAHMS, visit: the

National Animal Health Monitoring System online.

Monitoring for AMR and Evaluating Genetic Components
Veterinary clinics and diagnostic laboratories across the United States submit

samples to the National Animal Health Laboratory Network (NAHLN) to look for AMR

in pathogens routinely found in cattle, swine, horses, and poultry, as well as

domestic dogs and cats.

NAHLN updates the information in near real-time via a dashboard at the NAHLN AMR

Pilot Project. Through NAHLN’s centralized data collection and reporting, APHIS

monitors trends and identifies new or emerging resistance to current antimicrobials,

helps assess the continued usefulness of antimicrobials over time, and provides

guidance to veterinarians, producers, and other stakeholders. Scientists use the

information in a number of Federal, State, and academic collaborations, including

several that evaluate genetic components of AMR pathogens that cause diseases

such as diarrhea, pneumonia, and skin infections in our animal populations. 

APHIS’ National Veterinary Services Laboratories (NVSL) tests and diagnoses

antimicrobial susceptibility and is conducting several research studies related to

AMR genetics. One project, which analyzes Salmonella serotypes (a distinguishable

strain of a microorganism) for AMR genes, will provide baseline, comparison data for

outbreak investigations and future studies. NVSL is also studying reptile samples for

the presence of multi-drug resistant Salmonella, which scientists can then compare

to Centers for Disease Control and Prevention data.

Wildlife’s Part in AMR Transmission

Outbreak investigations show a pattern that wildlife can introduce diseases to

livestock and poultry. Understanding the role wildlife plays in spreading AMR

bacteria in the environment can help scientists identify risks to livestock and crops,

as well as preventive measures that could help protect agricultural operations.

Scientists at APHIS’ National Wildlife Research Center (NWRC) are developing AMR

bacteria diagnostics for wildlife. They are also conducting research on several

species to determine their potential for transmitting disease to livestock and crops.

NWRC identified multiple wildlife species, such as raccoons, gulls, and European

starlings, as hosts that can move AMR bacteria across wide areas and—in some

cases—continents.

NWRC also found that feral swine samples collected at landfills show resistance to

multiple antimicrobials. The samples also contained bacteria that were highly
resistant to antimicrobials like carbapenems that are considered antimicrobials “of

last resort” for complicated bacterial infections in people. The samples were also

resistant to fluoroquinolones, commonly used to treat many human and animal

illnesses. To learn more, visit:

Wildlife-borne Pathogens Affecting Food Safety and Security

Detection of Colistin-resistant E. coli in Feral Swine

Gulls as Source of Environmental Contamination by Colistin-resistant Bacteria

Continental-scale Dispersal of Antimicrobial Resistant Bacteria by Gulls

Role of European Starlings in Disseminating Multidrug-resistant E. coli

Education and Outreach

APHIS’ National Veterinary Accreditation Program includes trainings on the Use of

Antibiotics in Animals, the Veterinary Feed Directive, and the Role of Veterinarians in

Honey Bee Health. For more information about NVAP, visit: National Veterinary

Accreditation Program.

APHIS also educates dog breeders regulated under the Animal Welfare Act about the

risks of AMR and the importance of antimicrobial stewardship.

APHIS also educates dog breeders regulated under the Animal Welfare Act about the

risks of AMR and the importance of antimicrobial stewardship.

Future Directions

In addition to the activities outlined here, APHIS scientists are involved with national

and international efforts to understand and combat AMR through collaborations with

other agencies, non-profit organizations, and universities.

While the Food and Drug Administration regulates antimicrobial use in animals, AMR

demands a One Health, collaborative response from all of us. APHIS is committed to

growing our knowledge and pushing the science forward to inform smarter policy

solutions and protect valuable antimicrobial tools in the future.

For more information on AMR and the threat of AMR to human and agricultural

health, visit:

USDA Antimicrobial Resistance Action Plan

National Action Plan for Combating Antibiotic-Resistant Bacteria 2020-2025
Antibiotic Resistance Threats in the United States, 2019

Presidential Advisory Council on Combating Antibiotic-Resistant Bacteria

(PACCARB)

Meet Your APHIS Scientists

Many APHIS scientists are working on emerging genetic technologies. Here are just a

few:

Dr. Chelsey Shivley

APHIS-Veterinary Services

AMR Coordinator

Dr. Alan Franklin

APHIS-Wildlife Services

Ecology of AMR in Wildlife

Dr. Jeffrey Chandler

APHIS-Wildlife Services

Microbiology of AMR in Wildlife

Dr. Alice Green

APHIS-Veterinary Services

NAHMS AMR Specialist

Dr. Diana Short

APHIS-Veterinary Services

NAHMS Epidemiologist

Dr. Charles Fossler

APHIS-Veterinary Services

NAHMS Beef Specialist

Dr. Beth Harris

APHIS-Veterinary Services

NAHLN Associate Coordinator