Antibiotic resistance—consequences for animal health, welfare, and food production

Abstract

Most of the literature on the consequences of emergence and spread of bacteria resistant to antibiotics among animals relate to the potential impact on public health. But antibiotics are used to treat sick animals, and resistance in animal pathogens may lead to therapy failure. This has received little scientific attention, and therefore, in this article, we discuss examples that illustrate the possible impact of resistance on animal health and consequences thereof. For all animals, there may be a negative effect on health and welfare when diseases cannot be treated. Other consequences will vary depending on why and how different animal species are kept. Animals kept as companions or for sports often receive advanced care, and antibiotic resistance can lead to negative social and economic consequences for the owners. Further, spread of hospital-acquired infections can have an economic impact on the affected premises. As to animals kept for food production, antibiotics are not needed to promote growth, but, if infectious diseases cannot be treated when they occur, this can have a negative effect on the productivity and economy of affected businesses. Antibiotic resistance in animal bacteria can also have positive consequences by creating incentives for adoption of alternative regimes for treatment and prevention. It is probable that new antibiotic classes placed on the market in the future will not reach veterinary medicine, which further emphasizes the need to preserve the efficacy of currently available antibiotics through antibiotic stewardship. A cornerstone in this work is prevention, as healthy animals do not need antibiotics.

Effect of Tetracycline Dose and Treatment Mode on Selection of Resistant Coliform Bacteria in Nursery Pigs

“…They cause increased mortality from infectious diseases (1) and a higher cost of treatment due to the prolonged recovery time and the need for the use of more expensive antibiotics, and they increase the need for and the cost of biosecurity in hospitals (2). The same is true in veterinary medicine, where resistant bacteria increase the cost of treatment and may lead to animal welfare problems due to unsuccessful treatments (3,4). For these reasons, it is important to reduce the factors that result in the selection of antibioticresistant bacteria as much as possible.…”

“…The results showed no significant effect of the three most common additional treatments, and we ruled out the possibility that additional treatments were a confounding factor. After time point T 3 , pigs were distributed to different fattening units, and only a fraction of the pigs were resampled at T 4 . No records on antibiotic use covering the time periods from birth to T 1 and between T 3 and T 4 were available to us.…”

“…Finally, on one farm, pigs were often treated with amoxicillin before T 1 but received no other treatments between T 2 and T 3 . Antibiotic treatments between T 3 and T 4 were not consistently recorded and were thus not taken into account in the analyses. When analyzing for the effect of treatments with antibiotics before and after our treatments, there were no significant effects of the three additional treatments administered to the largest number of pigs (colistin treatment before T 1 , amoxicillin treatment before T 1 , and doxycycline treatment after T 2 ) on the absolute number of tetracycline-resistant coliform bacteria, the proportion of tetracycline-resistant coliforms, or the change in the proportion of tetracycline-resistant coliforms, and we concluded that these treatments were not confounders in our study.…”

A Systematic Review of Public Attitudes, Perceptions and Behaviours Towards Production Diseases Associated with Farm Animal Welfare

“…Despite their concern, the public may have very little or no understanding of modern farming practices and their impact on productivity and welfare (Harper and Henson 2001). The incidence of production diseases can increase in intensive systems, and can negatively affect FAW (Bengtsson and Greko 2014). The public represent an important user of the food-chain, and can drive demand for specific food products (Jensen 2006).…”

New Structural Templates for Clinically Validated and Novel Targets in Antimicrobial Drug Research and Development

“…R. Peterson 2009) associated with high mortality and morbidity (Pendleton et al 2013), there are concerns that the increasing lack of effective therapeutics could develop into a serious threat for public health, or even into a fallback to a so-called pre-antibiotic era (Piddock 2012;Ventola 2015;Wright 2015b). The anthropological reasons for this situation are manifold; they include the inadequate clinical use of existing antibiotics (Gilbert 2015;Sanchez and Demain 2015;Shiva 2015), extended misuse of antibiotics in intensive animal husbandry for food production (Bengtsson and Greko 2014;Littmann et al 2015), and the economically-driven exodus of big pharma companies from the antibiotics research field that contributed to the innovation gap mentioned above (Lowther 1979;Powers 2003;Projan 2003;Spellberg et al ; Tau es ; To es ; O Co ell et al . Beyond these anthropological acceleration forces (Breu et al 2001;Gillings 2013), we have to accept that bacterial resistance to antibiotics is not a side effect of modern drug therapy, but an inherent part of bacterial evolution to fight for their evolutionary niche with other bacteria and further organisms (Wright 2012;Wright and Poinar 2012;Rodríguez-Rojas et al 2013).…”