Antibiotic use in the United States poultry farming industry

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Antibiotic use in the United States poultry farming industry is the controversial prophylactic use of antibiotics in the country's poultry farming industry. It differs from the common practice in Europe, where antibiotics for growth promotion were disallowed in the 1950s.

Contents

Since their approval by the Food and Drug Administration (FDA) in 1951, antibiotics have been extensively used in large quantities. [1] Three years prior to their approval, scientists were investigating a phenomenon in which chickens that were exposed to bacteria-rich manure displayed signs of better health compared to those that were not. Testing revealed that chickens fed with a variety of vitamin B12 produced with the residue of a specific antibiotic grew 50% faster than chickens fed with B12 from a different source. [2] Further research confirmed that antibiotic use improved chicken health, resulting in increased egg production, lower mortality rates, and reduced illness. Consequently, farmers shifted from expensive animal proteins to comparatively inexpensive antibiotics and B12, as it enabled chickens to reach market weight faster and at a lower cost. With a growing population and increased demand, antibiotics seemed to be an ideal and cost-effective way to boost poultry output. However, in recent times, antibiotic use in poultry production has become a subject of debate because of concerns about bacterial antibiotic resistance. [3]

Emerging threats: antibiotic resistance

The Centers for Disease Control and Prevention (CDC) has identified the emergence of antibiotic resistance as a national threat. [4] The concern over antibiotic use in livestock arises from the necessity antibiotics have in keeping populations disease-free. As of 2016, over 70% of FDA approved antibiotics were utilized in modern, high production poultry farms to prevent, control, and treat disease. [5] The FDA released a report in 2009 estimating that 29 million pounds (13 kt) of antibiotics had been used in livestock in that year alone. [6] However, surveillance of consumer exposure to antibiotics through poultry consumption is limited. More specifically in 2012, the FDA speculated the most significant public health threat in regard to antimicrobial use in animals is the exposure of antimicrobial-resistant bacteria to humans. [7] These statements have been challenged by the American meat industry lobbyists, who posit that antibiotics are used responsibly and judiciously in order to ensure effectiveness. [8]

Consumer health effects

Consumers are exposed to antibiotic resistance through consumption of poultry products that have prior exposure to resistant strains. In poultry husbandry, the practice of using medically important antibiotics can select for resistant strains of bacteria, which are then transferred to consumers through poultry meat and eggs. The CDC acknowledges this transferral pathway in their 2013 report of Antibiotic Resistant Threats in the United States. [9] The annual rate of foodborne illness in America is one in six. For the 48 million individuals affected, antibiotics play a critical role in thwarting mortality rates. [10] In a literature review conducted by the Review of Antimicrobial Resistance 100 out of 139 studies found evidence of a link between antibiotic use in animals and antibiotic resistance in consumers. [6]

When a gram-negative bacterial infection is suspected in a patient, one of the first-line options for treatment is in the fluoroquinolone family. This, along with penicillin, is one of the first families of antibiotics utilized in the broiler industry. If this first-line treatment is not successful, a stronger class of antibiotics is typically used, however, there is a limitation on how many classes are available, as well as which medications are available on hospital formularies. There is also more drug toxicity affiliated with second and third line antibiotic options. This is one example why it is critical to keep as many first-line antibiotic options available for human use. [11]

Other issues are associated with duration and complexity of infection. On average, treatment for non-resistant bacteria is administered 11.5 hours after diagnosis, and treatment for resistant bacteria is administered 72 hours after diagnosis. [11] This is a reflection of the additional threat of prolonged incubation, leading to greater potential for systemic disease, with higher morbidity and mortality associated with opportunities for complications, and prolonged treatment time. For example, of the two million people affected by resistant infections a year, 23,000 will die. [12] Severity in mortality is coupled when exposed to high risk populations such as immunocompromised and elderly individuals in hospital and nursing home settings. [13]

History of federal policy on antibiotic use in livestock

Current U.S. federal regulators

National Antimicrobial Resistance Monitoring System's (NARMS) Enteric Bacteria program – Established in 1996, and represents a collaboration between the USDA, FDA, and CDC. Its purpose is to organize these organizations into a drug monitoring program for antibiotics utilized in animal feed with the goal of maintaining their medical efficacy. There are three branches which oversee humans, retail meat, and food animals. [16]

Vertical integration

This is the current business structure utilized almost universally in the broiler, or chicken bred for meat, industry. This also began in the 1940s when antibiotics began to be utilized in livestock feed. Perdue is credited as the pioneer of this structure. [18] The basis is centralization of production. "Integrators" control cost, policy, and are the decision makers of production. They decide feed formulations, choice of antibiotic administration, and cover those costs in addition to veterinary services. They also own the poultry that is grown. Farmers are labeled as "growers" or "operators." They own the land and buildings where the poultry is grown, and are essentially caretakers for the poultry growth to the integrators. [16] The benefit for growers in this business structure is they are guaranteed payment from the Integrators, which is compensated in weight gained by each flock. [19] Due to this structure, about 90% of broilers are raised within 60 miles of the processing plant. Integrators are large poultry companies such as Perdue, Tyson, Pilgrim's Pride, and Koch Foods. As of 2011, there were about 20 of these companies in the U.S. that controlled 96% of all broilers produced that year. [16]

Regulatory surveys

There are two main surveys distributed to farmers by the federal government to aid in various regulations of the agricultural industry. They are the Agricultural and Resource Management Survey (ARMS) and the National Animal Health Monitoring Survey (NAHMS). [16]

Agricultural and Resource Management Survey (ARMS) – Ran by the USDA's Economic Research Service (ERS) and National Agricultural Statistics Service (NASS). The main focus is finances of farming, production practices, and resource use. Seventeen total states are sampled every 5–6 years per livestock type, with the most recent surveys distributed to broiler farmers in 2006 and 2011. There was one question about utilization of antibiotics in poultry food or water, excluding use for illness treatment. [16]

Antibiotic-resistant outbreaks from poultry meat

In order to minimize and prevent any residues of antibiotics in chicken meat, any chickens given antibiotics are required to have a "withdrawal" period before they can be slaughtered. Samples of poultry at slaughter are randomly tested by the FSIS, and show a very low percentage of residue violations. [20] Although violations are minimal, these small amounts of antibiotics have still contributed to antibiotic resistant outbreaks in the U.S. There are five infectious agents that account for 90% of foodborne related deaths. Three consistently found in poultry are: Salmonella, Campylobacter, and Escherichia coli. [21]

Limitations and challenges

One obstacle to gathering more comprehensive data on the use of antibiotics in feed is the majority of the poultry industry utilizes vertical integration. As a consequence, farmers are often unaware of what components go into the feed, including whether or not antibiotics are used. [24] Also in antibiotic usage in general, there are criteria to define bacterial resistance to specific antibiotics, however, there are no standards to divide the bacteria into resistant and susceptible categories based on antibiotics utilized. [25]

The poultry industry also plays a large part in the United States economy, both in domestic purchasing and through international demand. The USDA reports that the United States is the "world's largest producer and second largest exporter of poultry meat." In 2010, it produced 36.9 billion pounds of broiler meat and exported 6.8 billion pounds of broiler meat. This equates to an estimated retail value of 45 billion dollars in 2010. [26]

Both the agricultural and pharmaceutical industries have been lobbying against legislation that seeks to quell non-therapeutic antibiotic use in livestock since the first introduction of such legislation in Congress in the 1970s. [27] Despite scientific evidence suggesting a strong association between antibiotic use in poultry and other livestock, agribusiness lobbies such as The National Chicken Council argue that there is not sufficient evidence to purport that there is a measurable impact to humans and shifts the blame of the problem of antibiotic resistance to overprescribing in the field of medicine. [28]

With antibiotic restrictions, integrators will bear the immediate costs of these changes, and would likely result in modified finances and contracts with growers. [16] Also, public health agencies may not have adequate scientific evidence for making appropriate decisions for better public health outcomes, secondary to lack of research funds. As a reference, America spends about $101 billion per year for both governmental and biomedical industrial research, which is only 5% of total health expenditures. [25]

Solutions

Several policies have been proposed to improve data collection and transparency in livestock production. For example, the 2013 Delivering Antimicrobial Transparency in Animals (DATA) Act proposed the enactment of policies to acquire more accurate documentation of antibiotic use in growth promotion by farmers, drug manufacturers, and the FDA. [29] The Preservation of Antibiotics for Medical Treatment Act (PAMTA) was enacted to eliminate the use of medically important antibiotics in livestock. [29] In 2015, the Preventing Antibiotic Resistance Act (PARA) was passed with two components: requirement of drug companies to provide evidence that antibiotics that are approved for use in poultry, and that meat production does not add to the growing threat of antibiotic resistance in humans. [30] Antimicrobial Stewardship Programs (ASPs) serve as an example of systematic monitoring and analysis of data via interdisciplinary and multi-sectoral collaboration. [31]

Performing quality improvement in the process of livestock production is another focus. Some alternative methods include "improving hygiene, using enzymes, probiotics, prebiotics, and acids to improve health and utilizing bacteriocins, antimicrobial peptides, and bacteriophages as substitutes for antibiotics." [31] Adaptations of methods by other countries is an additional focus. For example, the use of antibiotics in feed was banned in Sweden in 1985 with no compensatory increase in antibiotic usage in other sectors of production, proving that a ban can be successfully administered without unintended impacts on other categories. [32]

Major producers in the poultry industry have also begun to make strides towards change, largely due to public concern over the widespread use of antibiotics in poultry. Some producers have started eliminating the use of antibiotics in order to produce and market chickens that may legally be labeled "antibiotic free." In 2007, Perdue began phasing out all medically important antibiotics from its feed and hatcheries and began selling poultry products labeled "no antibiotics ever" under the Harvestland brand. Consumer response was positive and in 2014 Perdue also began phasing out ionophores from its hatchery and began using the "antibiotic free" labels on its Harvestland, Simply Smart and Perfect Portions products. [33]

Impacts of change

As Guidance for Industry #213 has been voluntarily accepted, it will be a violation of the Federal Food, Drug, and Cosmetic Act to use antibiotics in livestock production for non-therapeutic purposes. However, as there is now a requirement for veterinary oversight and approval for antibiotics use, there is leeway in the interpretation of non-therapeutic purposes dependent on the situation. For example, per the FDA, "a veterinarian may determine, based on the client's production practices and history, that weaned beef calves arriving at a feedlot in bad weather after a lengthy transport are at risk to develop a bacterial respiratory infection. In this case, the veterinarian might choose to preventively treat these calves with an antimicrobial approved for prevention of that bacterial infection." [34]

The FDA is not trying to regulate all antimicrobials at this time – only those antibiotics which are considered "medically important." For example, bacitracin, a common antibiotic found in over the counter antibiotic ointments, is not classified as "medically important." Ionophores, which are not a part of human medicine but given for improving the health of livestock, are also not included in this regulation. [14]

Related Research Articles

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An antibiotic is a type of antimicrobial substance active against bacteria. It is the most important type of antibacterial agent for fighting bacterial infections, and antibiotic medications are widely used in the treatment and prevention of such infections. They may either kill or inhibit the growth of bacteria. A limited number of antibiotics also possess antiprotozoal activity. Antibiotics are not effective against viruses such as the ones which cause the common cold or influenza. Drugs which inhibit growth of viruses are termed antiviral drugs or antivirals. Antibiotics are also not effective against fungi. Drugs which inhibit growth of fungi are called antifungal drugs.

<span class="mw-page-title-main">Antimicrobial resistance</span> Resistance of microbes to drugs directed against them

Antimicrobial resistance occurs when microbes evolve mechanisms that protect them from antimicrobials, which are drugs used to treat infections. This resistance affects all classes of microbes, including bacteria, viruses, protozoa, and fungi. Together, these adaptations fall under the AMR umbrella, posing significant challenges to healthcare worldwide. Misuse and improper management of antimicrobials are primary drivers of this resistance, though it can also occur naturally through genetic mutations and the spread of resistant genes.

<i>Campylobacter</i> Genus of gram-negative bacteria

Campylobacter is a type of bacteria that can cause a diarrheal disease in people. Its name means "curved bacteria", as the germ typically appears in a comma or "s" shape. According to its scientific classification, it is a genus of gram-negative bacteria that is motile.

<span class="mw-page-title-main">Drug resistance</span> Pathogen resistance to medications

Drug resistance is the reduction in effectiveness of a medication such as an antimicrobial or an antineoplastic in treating a disease or condition. The term is used in the context of resistance that pathogens or cancers have "acquired", that is, resistance has evolved. Antimicrobial resistance and antineoplastic resistance challenge clinical care and drive research. When an organism is resistant to more than one drug, it is said to be multidrug-resistant.

<span class="mw-page-title-main">Campylobacteriosis</span> Infection by Campylobacter bacteria

Campylobacteriosis is among the most common infections caused by a bacterium in humans, often as a foodborne illness. It is caused by the Campylobacter bacterium, most commonly C. jejuni. It produces an inflammatory, sometimes bloody, diarrhea or dysentery syndrome, and usually cramps, fever and pain.

<span class="mw-page-title-main">Salmonellosis</span> Infection caused by Salmonella bacteria

Salmonellosis is a symptomatic infection caused by bacteria of the Salmonella type. It is the most common disease to be known as food poisoning, these are defined as diseases, usually either infectious or toxic in nature, caused by agents that enter the body through the ingestion of food. In humans, the most common symptoms are diarrhea, fever, abdominal cramps, and vomiting. Symptoms typically occur between 12 hours and 36 hours after exposure, and last from two to seven days. Occasionally more significant disease can result in dehydration. The old, young, and others with a weakened immune system are more likely to develop severe disease. Specific types of Salmonella can result in typhoid fever or paratyphoid fever. Typhoid fever and paratyphoid fever are specific types of salmonellosis, known collectively as enteric fever, and are, respectively, caused by salmonella typhi and paratyphi bacteria, which are only found in humans. Most commonly, salmonellosis cases arise from salmonella bacteria from animals, and chicken is a major source for these infections.

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<span class="mw-page-title-main">Poultry farming</span> Part of animal husbandry

Poultry farming is the form of animal husbandry which raises domesticated birds such as chickens, ducks, turkeys and geese to produce meat or eggs for food. Poultry – mostly chickens – are farmed in great numbers. More than 60 billion chickens are killed for consumption annually. Chickens raised for eggs are known as layers, while chickens raised for meat are called broilers.

<span class="mw-page-title-main">Antibiotic misuse</span> Improper use of antibiotic medications

Antibiotic misuse, sometimes called antibiotic abuse or antibiotic overuse, refers to the misuse or overuse of antibiotics, with potentially serious effects on health. It is a contributing factor to the development of antibiotic resistance, including the creation of multidrug-resistant bacteria, informally called "super bugs": relatively harmless bacteria can develop resistance to multiple antibiotics and cause life-threatening infections.

<span class="mw-page-title-main">Animal Drug Availability Act 1996</span> US law

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<span class="mw-page-title-main">Subtherapeutic antibiotic use in swine</span>

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<span class="mw-page-title-main">Antibiotic use in livestock</span> Use of antibiotics for any purpose in the husbandry of livestock

Antibiotic use in livestock is the use of antibiotics for any purpose in the husbandry of livestock, which includes treatment when ill (therapeutic), treatment of a group of animals when at least one is diagnosed with clinical infection (metaphylaxis), and preventative treatment (prophylaxis). Antibiotics are an important tool to treat animal as well as human disease, safeguard animal health and welfare, and support food safety. However, used irresponsibly, this may lead to antibiotic resistance which may impact human, animal and environmental health.

<span class="mw-page-title-main">Feed manufacturing</span> Production of animal feed

Feed manufacturing refers to the process of producing animal feed from raw agricultural products. Fodder produced by manufacturing is formulated to meet specific animal nutrition requirements for different species of animals at different life stages. According to the American Feed Industry Association (AFIA), there are four basic steps:

  1. Receive raw ingredients: Feed mills receive raw ingredients from suppliers. Upon arrival, the ingredients are weighed, tested and analyzed for various nutrients and to ensure their quality and safety.
  2. Create a formula: Nutritionists work side by side with scientists to formulate nutritionally sound and balanced diets for livestock, poultry, aquaculture and pets. This is a complex process, as every species has different nutritional requirements.
  3. Mix ingredients: Once the formula is determined, the mill mixes the ingredients to create a finished product.
  4. Package and label: Manufacturers determine the best way to ship the product. If it is prepared for retail, it will be "bagged and tagged," or placed into a bag with a label that includes the product's purpose, ingredients and instructions. If the product is prepared for commercial use, it will be shipped in bulk.

Salmonellosis annually causes, per CDC estimation, about 1.2 million illnesses, 23,000 hospitalizations, and 450 deaths in the United States every year.

The poultry microbiome is an understudied, yet extremely impactful part of the poultry industry. Poultry is defined as any avian species used for production purposes such as food or down feathers. The United States consumes more poultry, specifically broiler meat, than any other type of protein. Worldwide, poultry makes up 33% of consumed meat. This makes poultry extremely valuable and the impact of the poultry microbiome on health and production even more valuable. Antonie van Leeuwenhoek was the first to notice microbes inside animals through stool samples giving light to further research into the gut microbiome. His discovery lead to the ever evolving study of the microbiota and microbiome. The microbiota is the entirety of living organisms including bacteria, viruses, fungi, and archaea in an environment. The microbiome is the combination of the microbiota and the additional activities in that system including metabolites and chemicals in a habitat. Much of the work done to characterize the poultry microbiome has been accomplished over the past decade and was done through the use of 16s rRNA sequencing.

References

  1. ↑ Castonon, J.R. History of the Use of Antibiotics Archived 2016-12-05 at the Wayback Machine [Poultry Science, 2011].
  2. ↑ Ogle, Maureen. "Riots, Rage, and Resistance: A Brief History of How Antibiotics Arrived on the Farm". Scientific American. Sep 3, 2013. Retrieved 28 October 2016.
  3. ↑ Roth, Natalia. "How to reduce antibiotic resistance on poultry farms." July 27, 2016. Retrieved 28 October 2016.
  4. ↑ CDC. "Antibiotic Resistant Threats in the United States" CDC 2013.
  5. ↑ O’Niel, Jim. “Antimicrobials in the agriculture and the environment: Reducing the unnecessary use and waste” The Review on Antimicrobial Resistance. 2016.
  6. 1 2 O’Niel, Jim. “Review on Antimicrobial Resistance” December 2015.
  7. ↑ Federal Register. “Rules and Regulations” 2012.
  8. ↑ American Meat Institute. “The Facts About Antibiotics in Livestock & Poultry Production”.
  9. ↑ CDC. "Antibiotic Resistance Threats in the United States 2013", April 23, 2013. Retrieved on 28 October 2016.
  10. ↑ CDC. “Estimates of foodborne illness in the United States” 2011.
  11. 1 2 Lautenbach, et al. "Extended-Spectrum β-Lactamase-Producing Escherichia coli and Klebsiella pneumoniae: Risk Factors for Infection and Impact of Resistance on Outcomes", Clinical Infectious Disease, 2001. Retrieved on 28 October 2016.
  12. ↑ CDC. "Antibiotic Resistance Threats in the United States 2013", April 23, 2013. Retrieved on 28 October 2016.
  13. ↑ CDC. “Antibiotic Resistant Threats in the United States” 2013.
  14. 1 2 Grow, Brian; Huffstutter, PJ; Erman, Michael (2014-09-15). "The drugs fed to farm animals and the risks posed to humans: Farmaceuticals". reuters.com. Retrieved 2020-05-14.
  15. ↑ U.S. FDA. "Phasing out certain antibiotics use in farm animals", Dec 11, 2013. Updated Feb 25, 2015. Retrieved on 28 October 2016.
  16. 1 2 3 4 5 6 7 8 Sneeringer, et al. "Economics of Antibiotic Use in U.S. Livestock production" Archived 2016-05-17 at the Wayback Machine , USDA , November 2015. Retrieved on 28 October 2016.
  17. ↑ "Organic Regulations". ams.usda.gov. United States Department of Agriculture. Retrieved 2020-05-14.
  18. ↑ Pelton, Tom. "New Book Explains How Perdue's "Chickenizing" Changed the World", 'WYPR', Sep 8, 2016. Retrieved on 28 October 2016.
  19. ↑ "Vertical Integration", National Chicken Council , 2012. Retrieved on 28 October 2016.
  20. ↑ "Chicken from Farm to Table | USDA Food Safety and Inspection Service". Fsis.usda.gov. April 6, 2011. Archived from the original on September 3, 2011. Retrieved August 26, 2011.
  21. ↑ “The Human Health Impact of Antimicrobial Resistance in Animal Populations” 2011.
  22. ↑ CDC. "Multistate Outbreak of Multi-Drug Resistant Salmonella Heidelberg Infections Linked to Foster Farms Brand Chicken (Final Update)". 31 July 2014.
  23. ↑ CDC. "Multistate Outbreak of Multi-Drug Resistant Salmonella Enteriditis Infections Linked to Raw, Frozen, Stuffed Chicken Entrees Produced by Barber Foods (Final Update)" 16 October 2015.
  24. ↑ S. Sneeringer, "Restrictions on Antibiotic Use for Production Purposes in U.S. Livestock Industries Likely To Have Small Effects on Prices and Quantities", Amber Waves, November 2015.
  25. 1 2 Dorsey, ER; de Roulet, J; Thompson, JP; Reminick, JI; Thai, A; WhiteStellato, Z; et al. (2010). "Funding of US biomedical research, 2003–2008". JAMA. 303 (2): 137–43. doi:10.1001/jama.2009.1987. PMC   3118092 . PMID   20068207.
  26. ↑ D. Harvey, "Poultry & Eggs: Statistics & Information," Amber Waves Magazine, 22 August 2016.
  27. ↑ S. Tavernise, "F.D.A. Restricts Antibiotic Use for Livestock," The New York Times, 11 December 2013.
  28. ↑ Frontline. “Modern Meat: Antibiotic Debate Overview”
  29. 1 2 "U.S. Congressional Legislation Relating to Antibiotic Use, 2004–2014", Washington D.C.
  30. ↑ The Pew Charitable Trusts. "New Antibiotics Bill Addresses the Threat of Superbugs" 2 March 2015.
  31. 1 2 L. Chang-Ro, H. C. Ill, C. J. Byeong and H. L. Sang, "Review Strategies to Minimize Antibiotic Resistance," International Journal of Environment Research and Public Health, 2013.
  32. ↑ Gilchrist, M. J.; Greko, C.; Wallinga, D. B.; Beran, G. W.; Riley, D. G.; Thorne, P. S. (2007). "The Potential Role of Concentrated Animal Feeding Operations in Infectious Disease Epidemics and Antibiotic Resistance". Environmental Health Perspectives. 115 (2): 313–316. doi:10.1289/ehp.8837. PMC   1817683 . PMID   17384785.
  33. ↑ Stephanie Strom (July 31, 2015). "Perdue Sharply Cuts Antibiotic Use in Chickens and Jabs at Its Rivals". The New York Times. Retrieved August 12, 2015.
  34. ↑ "FDA's Strategy on Antimicrobial Resistance – Questions and Answers". fda.gov. December 2013. Retrieved 2020-05-14.

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