AMR in Argentine Broiler Poultry Systems: Risks and Mitigation
Lead Research Organisation:
University of Nottingham
Department Name: Sch of Biosciences
Abstract
Intensive poultry production is characterised by high antimicrobial use (AMU) and associated environmental and human risks. This proposal offers five linked interdisciplinary work packages that aim to establish a strategic research program in antimicrobial resistance (AMR) in broiler farms in Argentina. It will integrate ex situ experiments with field trials on commercial broiler farms, quantifying AMR associated with broiler production and the role of litter in AMR-related risks to birds, humans and the environment. The key aim of the proposal is to develop a framework to understand AMR transference to the environment and evaluate the scientific evidence to inform interventions for suitable litter management practices in commercial broiler farms in Argentina, and more widely in LMICs. This framework will be based on empirical data collected from commercial broiler farms in Argentina and from laboratory-scale experiments (UK and Argentina) and developed via a quantitative model for spread and amelioration of AMR and the related impact on poultry productivity and welfare. The focus of the project will be the presence and persistence of AMR in poultry litters and how to mitigate spread to the environment. For this purpose, field trials will be performed in commercial Argentinian broiler farms and laboratory-scale experimental work in Argentina and UK. Data analysis will be carried out in both countries. A series of integrated work packages (WPs) will answer the four Research Questions with two additional work packages designed to address the two key objectives.
WP1: On-farm characterization of AMR status, litter management and production performance to determine how different AMU protocols and litter management strategies affect persistence of AMR determinants and bird performance; setting baseline prevalence and diversity of AMR determinants in commercial farms.
WP2: Optimising litter sanitising processes. To inform best practice by conducting composting trials in UK and Argentina under controlled conditions to simulate temperature and humidity of poultry sheds. Data obtained from field (WP1) and laboratory testing will feed into the model (WP4) and the best practice framework (WP5). Litter will be obtained from farms with different AMU strategies as described in WP1.
WP3: Phenotypic and molecular characterization of AMR of indicator bacteria and resistance genes. This work-package will determine environmental indicators to measure AMR in different scenarios with/without antimicrobials in selected farms. It will also search for a reference genome for novel strains-linkage of AMR.
WP4: Modelling AMR through the litter cycles, WP4 will develop a quantitative model for spread and amelioration of AMR in chicken litter, taking into account the production cycle and subsequent composting. Results from WP1 (field data) and WP2 (experimental data) will contribute to determine pathways from AMU to the litter.
WP5: Systems approach to understanding AMR dynamics with broiler productive performance/health and welfare. Here, data collected and analytical outputs from work packages 1-4 will be integrated into a systems model to identify key predictors for the emergence and transmission of AMR bacteria within the Argentine broiler agricultural system.
The project aims to understand how AMR persists in broiler farms through different productive cycles and spreads to the environment. Additionally, we propose to co-design cost-effective interventions to reduce the impact of AMR from poultry farms by promoting a rationale for AMU and waste management which will potentially influence on-farm behaviour. The project will offer data to develop knowledge-based policies and waste management/biosecurity recommendations which can be transferred to the development of LMIC strategies for managing AMU/AMR in poultry production.
WP1: On-farm characterization of AMR status, litter management and production performance to determine how different AMU protocols and litter management strategies affect persistence of AMR determinants and bird performance; setting baseline prevalence and diversity of AMR determinants in commercial farms.
WP2: Optimising litter sanitising processes. To inform best practice by conducting composting trials in UK and Argentina under controlled conditions to simulate temperature and humidity of poultry sheds. Data obtained from field (WP1) and laboratory testing will feed into the model (WP4) and the best practice framework (WP5). Litter will be obtained from farms with different AMU strategies as described in WP1.
WP3: Phenotypic and molecular characterization of AMR of indicator bacteria and resistance genes. This work-package will determine environmental indicators to measure AMR in different scenarios with/without antimicrobials in selected farms. It will also search for a reference genome for novel strains-linkage of AMR.
WP4: Modelling AMR through the litter cycles, WP4 will develop a quantitative model for spread and amelioration of AMR in chicken litter, taking into account the production cycle and subsequent composting. Results from WP1 (field data) and WP2 (experimental data) will contribute to determine pathways from AMU to the litter.
WP5: Systems approach to understanding AMR dynamics with broiler productive performance/health and welfare. Here, data collected and analytical outputs from work packages 1-4 will be integrated into a systems model to identify key predictors for the emergence and transmission of AMR bacteria within the Argentine broiler agricultural system.
The project aims to understand how AMR persists in broiler farms through different productive cycles and spreads to the environment. Additionally, we propose to co-design cost-effective interventions to reduce the impact of AMR from poultry farms by promoting a rationale for AMU and waste management which will potentially influence on-farm behaviour. The project will offer data to develop knowledge-based policies and waste management/biosecurity recommendations which can be transferred to the development of LMIC strategies for managing AMU/AMR in poultry production.
Technical Summary
The main purpose of this project is to establish a strategic research programme in antimicrobial resistance (AMR) associated with broiler poultry production in Argentina. We will quantify AMR associated with broiler production and the role of the common practice of re-using litter (bedding) during production cycles, and determine AMR-related risks to birds, humans and the environment. In so doing, we will establish how different litter treatments and antimicrobial use drives selection and spread of AMR.
The key aim is to develop a framework for best practice for litter management in commercial broiler farms in Argentina. The framework will be based on empirical data collected from commercial farms and from laboratory-scale experiments. The framework will be developed via a quantitative model for spread and amelioration of AMR and the related impact on poultry productive performance and welfare. This will be predicated on the outputs of five work packages which will: (i) Characterise on-farm AMR status, litter management and productive performance; (ii) optimise the litter sanitation process; (iii) use phenotypic and molecular techniques to characterise AMR of indicator bacteria and resistance genes; (iv) model AMR through the litter cycles and (v) use a systems approach to understand AMR dynamics and identify key predictors for the emergence and transmission if AMR bacteria within the broiler agri-system, including whole-animal health and welfare drivers.
Therefore, the two main objectives of the project are to: (i) develop a quantitative model to predict AMR through the litter cycles taking into account the production cycle (differences in environment/husbandry/bird density) and subsequent composting and (ii) to develop a framework for best practice for commercial farms in Argentina and LMICs which use similar broiler production strategies.
The key aim is to develop a framework for best practice for litter management in commercial broiler farms in Argentina. The framework will be based on empirical data collected from commercial farms and from laboratory-scale experiments. The framework will be developed via a quantitative model for spread and amelioration of AMR and the related impact on poultry productive performance and welfare. This will be predicated on the outputs of five work packages which will: (i) Characterise on-farm AMR status, litter management and productive performance; (ii) optimise the litter sanitation process; (iii) use phenotypic and molecular techniques to characterise AMR of indicator bacteria and resistance genes; (iv) model AMR through the litter cycles and (v) use a systems approach to understand AMR dynamics and identify key predictors for the emergence and transmission if AMR bacteria within the broiler agri-system, including whole-animal health and welfare drivers.
Therefore, the two main objectives of the project are to: (i) develop a quantitative model to predict AMR through the litter cycles taking into account the production cycle (differences in environment/husbandry/bird density) and subsequent composting and (ii) to develop a framework for best practice for commercial farms in Argentina and LMICs which use similar broiler production strategies.
Planned Impact
This is an integrative study that focuses on poultry litter as the source of AMR. Our aim is to determine whether bacteria in the litter persist over the different productive litter cycles and whether the AMR determinants disseminating via various etiologic agents (e.g. flies) also have the potential to further disseminate resistance to the population. As a consequence, the key beneficiaries of this project will be general population, the farmers and poultry workers who rear broilers and therefore come into regular contact with poultry litter. In particular, those who compost and spread litter within the closed shed environment will be subject to breathing in and possibly ingesting dust particles containing antibiotic resistant bacteria, and this could be a serious health hazard.
Chicken consumption is increasing as a source of cheap protein and intensive production methods rely on extensive use of antibiotics. Use of antibiotics often results in a high proportion of chicken carcasses that are contaminated with multidrug resistant bacteria. AMR bacteria are present in healthy broilers and this indicates potential risks for transfer to the environment and to humans, either during husbandry procedures, composting the litter or by eating a contaminated bird. In addition to poultry workers, consumers are therefore at risk and the burden of Salmonella, Campylobacter or E. coli infections is high in children and the elderly. An added complication in Argentina and other LMICs is the reuse of litter from one flock to another and the possibility of enhancing survival and spread of antibiotic resistant bacteria and genes. Therefore, the outcomes of this project will benefit poultry farmers through: (1) improvements in litter composting methods which reduce AMR within the poultry sheds; (2) lower levels of AMR bacteria will benefit broiler health and improve production efficiency, both of which translate into increased profit margins. Furthermore, consumers will benefit by not eating chicken containing drug resistant bacteria.
The success of the project will be measured by (1) understanding the drivers of AMR within poultry sheds and (2) optimising an economically viable intervention for reducing prevalence of AMR in poultry litter.
Chicken consumption is increasing as a source of cheap protein and intensive production methods rely on extensive use of antibiotics. Use of antibiotics often results in a high proportion of chicken carcasses that are contaminated with multidrug resistant bacteria. AMR bacteria are present in healthy broilers and this indicates potential risks for transfer to the environment and to humans, either during husbandry procedures, composting the litter or by eating a contaminated bird. In addition to poultry workers, consumers are therefore at risk and the burden of Salmonella, Campylobacter or E. coli infections is high in children and the elderly. An added complication in Argentina and other LMICs is the reuse of litter from one flock to another and the possibility of enhancing survival and spread of antibiotic resistant bacteria and genes. Therefore, the outcomes of this project will benefit poultry farmers through: (1) improvements in litter composting methods which reduce AMR within the poultry sheds; (2) lower levels of AMR bacteria will benefit broiler health and improve production efficiency, both of which translate into increased profit margins. Furthermore, consumers will benefit by not eating chicken containing drug resistant bacteria.
The success of the project will be measured by (1) understanding the drivers of AMR within poultry sheds and (2) optimising an economically viable intervention for reducing prevalence of AMR in poultry litter.
