Antibiotics in Animal Health

Huge amounts of antibiotics are administrated annually to almost all domestic animal species for treatment or prophylaxis of infectious diseases or as feed additives for their growth-promoting effect. Antibiotics are needed to fight infectious diseases caused by specific animal pathogens. The development of new antibiotics with higher efficacy and lower toxicity remains of tremendous importance. However, antibiotics alter the microbiota of animals, possibly leading to an impaired health status. Additionally, antibiotic pressure can result in the selection of antibiotic resistances in specific pathogens but also in the natural microbiota of animals. The antibiotics administered and the selected resistant microorganisms are released into the environment. Humans can also be contaminated by these antibiotics and resistant bacteria through direct contact with animals or indirectly through the consumption of food products. Many bacterial species (especially those of the gut microbiota) are shared between humans and animals. Furthermore, specific animal pathogens can be transmitted to humans in the context of zoonotic diseases. Overall, the use of antibiotics in animals has a significant impact on the environment and animal and human health. A one-health approach is needed to monitor and control the potential consequences of the administration of antibiotics in animals.