Antibiotic resistance in animal nutrition
An overview of Konrad J Domig's presentation by Matt Holmes, Features editor, International Aquafeed
Antibiotics were placed firmly on the agenda at Biomin"s World Nutrition Forum in Cape Town. Konrad J Domig, of the BOKU University of Natural Resources and Life Sciences, Vienna, spoke about the relevance of antibiotic resistance in animal nutrition.
"Since their discovery, antibiotics have been widely used in human and veterinary medicine. The fundamental problem of antibiotic resistance development has long been known and was initially countered with the development of new active substances.
"After hardly any new active ingredients have been approved in the last two decades, the fundamental problem of the widespread use of antibiotic agents has become acute. This challenge has been taken up by different legislative bodies with different approaches to implementation."
This also concerns the possible application of antibiotic agents in the practice of livestock farming. Mr Domig said, in addition to the challenge of antibiotics resistance in livestock husbandry, further drivers of the problem can be named.
"A rapidly increasing human population that in parallel develops a disproportionality high demand for animal protein for nutrition, as well as challenges in the supply of drinking water and the disposal of municipal wastewater and waste. It should be emphasised that the antibiotic resistance problem that currently exists in human medicine has also mainly developed in this environment.
"On the other hand recent resistance monitoring data show a strong linkage of resistance development in human and veterinary medicine and both of them can be seen as drivers of the antibiotic resistance development in the environment."
Mr Domig added that any use of antimicrobial substances leads to resistance development in microorganisms. This also applies to other antimicrobials such as disinfectants and heavy metals.
"The underlying resistant microorganisms or resistance genes can nowadays be detected not only in the application environment, but also far away. In the end the direct danger to humans lies in the potential treatment failure of infections that means that no effective antibiotics are available against defined multidrug-resistant pathogens."
Mr Domig says that a large number of monitoring systems in human and veterinary medicine are established.
"Regardless of the discussion concerning the complete recording of the amounts of antibiotics used and their correct assignments to the treated animal equivalents, as well as the critically considered random sample analysis of selected indicator bacteria, they nevertheless provide a rough insight into the global development of antibiotic resistance."
Mr Domig says that a number of small steps is needed in order to achieve the future viability of livestock production. This strategic approach can be summarised by the European Food Safety Authority"s (EFSA) keywords: reduce, replace, rethink.
It is also important to evaluate the use of antimicrobial agents in the context of risk considerations and to consider appropriate alternative measures and to implement them with corresponding success.
"Although the current situation of the resistance developed in the livestock sector is still a small direct threat to the consumer, it is important to be active on a broad front," said Mr Domig.
A corresponding risk assessment for the spread of microbial resistance must also assess the risks of the alternatives and should include risks in livestock husbandry and risks along the food chain, in the consumer sector and in the environment.
"The multiple challenges of minimising antibiotic resistance require a risk-based use of antibiotics combined with high levels of management and hygiene and appropriate on-demand animal nutrition. The further development of preventive measures (from animal breeding to vaccinations), drug development (From new antibiotics up to new principles of action) as well as novel feeding concepts are necessary to make modern livestock farming economical and sustainable."