Key Facts You Need to Know About Antibiotic Reduction.
Over the years, the necessity of antibiotic reduction in animal production has become a global endeavor. Driven by the emergence of multi-resistant bacteria and the need for a one-health concept, most countries now have legislation to regulate antibiotic use. The quickly evolving market demands and feed industry solutions prompt us to take a fresh look on this complex topic.
What are antibiotics used for?
Antibiotics are substances which are able to kill or inhibit the growth of bacteria. In the global perspective, we see regional differences as to whether they are used only to treat or also to prevent bacterial infections. They may be classified by their chemical properties and by their modes of action. For the use in livestock, they are mostly available as medication for oral application via feed or drinking water or as injectable substance. Their safety and efficacy have been proven in clinical trials. Veterinary preparations containing antibiotics are strictly regulated by authorities.
In animal production, antibiotics are necessary for the treatment of diseases. Their use is, in most countries, obliged to registrations. These include specifications regarding
Species to be treated
Indications
Duration of treatment
Dosage to be used
The withdrawal period
The withdrawal period describes the amount of time that has to pass from the last application of the antibiotic until the meat or milk of the treated animal can be used safely again for human consumption.
For decades, certain antibiotic substances such as bacitracin, carbadox, salinomycin, virginiamycin and many more have also been used in animal feed to function as antibiotic growth promoters, so called AGPs. Used in subtherapeutic dosages, these substances have a positive impact on the biological performance of livestock. By modulating the intestinal microbiome, AGPs can improve the feed conversion ratio and the daily weight gain. To a limited extend, they also control the spread of possibly pathogenic bacteria in the intestine.
The use of AGPs makes up a significant portion of the worldwide antibiotic use in livestock. It has become an established, cheap way to secure performance.
The problem of antimicrobial resistance.
In the last two decades, the increasing occurrence of antibiotic-resistant bacteria has started to pose a serious health threat to both humans and animals. Through the excessive and frequent use of antibiotics, some bacteria have been able to develop resistances to one or more classes of antibiotics. This is known as AMR (antimicrobial resistance). The occurrence of AMR is linked to heavy use of antibiotics both in animal production and the human health sector. Especially in countries where antibiotics can be bought without a prescription or those without treatment guidelines, antibiotics are often over-prescribed by health workers and veterinarians.
Some classes of antibiotics are used for both veterinary and human treatment alike. Through a shared environment and contamination mechanisms, some resistant bacteria can spread between animal and human populations, they have zoonotic potential. Common infections that have usually been easy to treat with a course of antibiotics may thus become life-threatening.
Figure 1: Source: bioMérieux SA (2020) https://amr.biomerieux.com/en/challenges/from-farm-to-food-to-people-one-health/
Some antibiotics have been classified as reserve antibiotics. They are oftentimes used as drug of last resort in infections with multi-resistant bacteria.
The use of reserve antibiotics such as
polymyxins
3rd and 4th generation cephalosporins
fluoroquinolones
in animals is more and more being viewed critically. Some legislators call for exclusive use of these substances in humans to reduce the risk of further resistance developments.
More information can be found here: https://www.who.int/health-topics/antimicrobial-resistance
What has been done so far?
The One Health approach propagated by the World Health Organization (WHO) recognizes the relationship between animal and human health. To combat the overuse of antibiotics and the threat of AMR, it is necessary to promote the prudent use of antibiotics in both sectors.
Health authorities in the EU have already recognized the need to reduce the veterinary use of antibiotics at the end of the last century. The use of AGPs is banned in the EU since 2006. Since 2011, the European Medicines Agency (EMA) is monitoring the use of antibiotics in their European Surveillance of Veterinary Antimicrobial Consumption (ESVAC) project. A report is released annually.
Monitoring the use of antibiotics, with a special focus on reserve antibiotics, puts pressure on member countries to implement legislature to regulate and limit their use. The latest ESVAC report noted that the sales of veterinary antibiotics in European countries dropped by more than 34% between 2011 and 2018. Between 2011 and 2019, the use of veterinary antibiotics has dropped by even 60% in Germany alone.
Figure 2 Source: European Medicines Agency Science Medicines Health (2011-2018)
What are the challenges?
As the European Union, and also the US, is leading the way in reducing veterinary antibiotic usage, more and more countries are following up in tightening their regulations. Several countries in southeastern Asia are currently banning AGPs.
In therapeutic dosages, antibiotics are frequently used to treat digestive disorders. It is estimated that this makes up 50% of the uses in poultry and about 30% of uses in pig production. These numbers are expected to rise with the elimination of AGPs. Targeting intestinal health thus provides a large potential for antibiotic reduction.
There is an increasing consumer awareness for antibiotic use and also animal welfare. The call for antibiotic reduction provides marketing opportunities for food producers: meat is advertised as “NAE” (no antibiotics ever) or “ABF” (antibiotic free). We need to carefully weigh between the need for antibiotic reduction and the maintenance of animal welfare. The necessary treatment of sick animals should not be put at risk by market pressure.
Another market trend is the general rising demand for poultry meat. Especially in developing and strongly populated countries, poultry meat is growing in popularity. This sector is expected to expand significantly in the near future. Due to the high performance, short fattening period and efficient feed conversion of broiler chicken, poultry meat is relatively easy and quickly to produce, even under suboptimal conditions.
Figure 3: Data provided by FAOSTAT. Poultry production increased by almost 30% between 2010 and 2019.
And what are the solutions?
The feed industry has stepped up to this challenge. The potential loss of performance and also the maintenance of gut health can be addressed with effective and innovative feeding concepts. There is probably not one single feed additive to compensate the performance-boosting effects of AGPs. Comprehensive research has been conducted in this field, resulting in a wide array of additives and complementary solutions available on the market. Feed producers and nutritionists can use and combine these to provide effective solutions that are best adapted to regional differences.
Some examples of feed additive solutions targeting intestinal health are:
Probiotics
Prebiotics
Organic acids
Phytobiotics
Toxin binders
Of these, probiotics are most likely the best documented and widely used. While their benefit on intestinal health is well proven and recognized, the industry is continuously researching and identifying new strains to improve their efficacy. On the one hand, they can be used to improve animal performance by increasing digestibility and supporting the development of the gut. On the other hand, some strains are suitable to target specific pathogens and lowering the risk of intestinal disorders, thus reducing the need for antibiotic intervention and securing the health status.
You can find out more about probiotics in general here, or about the benefits of probiotic-containing feeding concepts for poultry, swine and ruminants production.
Outlook on current and future developments.
In some of the countries with the highest increase in poultry meat demand, the rearing conditions for broilers are rather inadequate. Inconsistent feedstuff qualities, challenging sanitary conditions and high endemic pathogen pressure are some of the hurdles to producing poultry meat sustainably without the overuse of antibiotics.
In the recent past, the COVID-19 crisis threatened a significant part of the livestock sector. The deterioration of gastronomy markets, plummeting meat prices, and false rumors about SARS-CoV-2 infections related to poultry meat consumption threw an entire industry sector off track.
Will some producers revert back to cheap AGP solutions instead of maintaining the use of sustainable alternatives? This might be an attractive short-term solution for the current market situation. But in the long run, the investment in high-quality feed solutions will be the only option to simultaneously secure human health, animal welfare and performance and consumer demands.
Contact your local Biochem sales representatives to find out how we can support you to continue and improve your production!
