Antimicrobial use in agriculture: critical review of the factors influencing behaviour

Recording antimicrobial use on Irish dairy farms: Barriers and facilitators to using technology and sharing data

Antimicrobial use (AMU) data are essential to monitor the effect of AMU reduction strategies in animal health. The use of technology and herd recording software to record AMU will be vital to scale the collation of these data in the future. The aim of this study was to determine the barriers and facilitators to Irish dairy farmers recording their AMU using a herd recording software and sharing AMU data. Thirty-three Irish dairy farmers involved in a study on AMU monitoring were asked to record their AMU using a herd recording software over a 12-mo period. At the end of the 12-mo period, 10 of these farmers were selected to take part in semi-structured interviews exploring their opinions on recording AMU, the use of herd recording software, and sharing AMU data. Interviews were transcribed and qualitatively analyzed using inductive thematic analysis. Several barriers and facilitators to farmers recording their AMU using a herd recording software and sharing AMU data were identified. Barriers included the age and generation of the farmer, farm infrastructure, a lack of training and education, a lack of knowledge around the benefits of digital data, a lack of incentive to digitize records, and a fear of repercussions. Facilitators identified by the farmers included the benefits of having instantly available data for making herd management decisions, reduced paperwork, increased organization for inspections, and a potential positive effect on the image of the dairy industry. To increase the uptake of new technology to record AMU at farm-level, farmers will need support in terms of education and training around the software available to them and reassurance around the perceived risks of repercussions with sharing data in a digital format.

Risk factors for antimicrobial use in Dutch pig farms: A cross-sectional study

BACKGROUND

Antimicrobial use (AMU) has decreased significantly in Dutch pig farms since 2009. However, this decrease has stagnated recently, with relatively high AMU levels persisting mainly among weaners. The aim of this study was to identify farm-level characteristics associated with: i) total AMU and ii) use of specific antimicrobial classes.

METHODS

In 2020, cross-sectional data from 154 Dutch pig farms were collected, including information on AMU and farm characteristics. A mixed-effects conditional Random Forest analysis was applied to select the subset of features that was best associated with AMU.

RESULTS

The main risk factors for total AMU in weaners were vaccination for PRRS in sucklings, being a conventional farm (vs. not), high within-farm density, and early weaning. The main protective factors for total AMU in sows/sucklings were E. coli vaccination in sows and having boars for estrus detection from own production. Regarding antimicrobial class-specific outcomes, several risk factors overlapped for weaners and sows/sucklings, such as farmer's non-tertiary education, not having free-sow systems during lactation, and conventional farming. An additional risk factor for weaners was having fully slatted floors. For fatteners, the main risk factor for total AMU was PRRS vaccination in sucklings.

CONCLUSIONS

Several factors found here to be associated with AMU. Some were known but others were novel, such as farmer's tertiary education, low pig aggression and free-sow systems which were all associated with lower AMU. These factors provide targets for developing tailor-made interventions, as well as an evidence-based selection of features for further causal assessment and mediation analysis.

A Rapid and Inexpensive PCR Test for Mastitis Diagnosis Based on NGS Data

Mastitis is a common mammary gland disease of dairy cattle caused by a wide range of organisms including bacteria, fungi and algae. Mastitis contributes to economic losses of dairy farms due to reduced yield and poor quality of milk. Since the correct identification of pathogens responsible for the development of mastitis is crucial to the success of treatment, it is necessary to develop a quick and accurate test to distinguish the main pathogens causing this disease. In this paper, we describe the development of a test based on the multiplex polymerase chain reaction (PCR) method allowing for the identification of Streptococcus agalactiae, Streptococcus dysgalactiae, Streptococcus uberis and Staphylococcus aureus. When creating our test, we relied on the results from new generation sequencing (NGS) for accurate determination of species affiliation. The multiplex PCR test was verified on 100 strains including veterinary samples, ATCC and Polish Collection of Microorganisms (PCM) reference strains. The obtained results indicate that this test is accurate and displays high specificity. It may serve as a valuable molecular tool for the detection of major mastitis pathogens.

Survey of farm, parlour and milking management, parlour technologies, SCC control strategies and farmer demographics on Irish dairy farms

BACKGROUND

This cross-sectional study describes a survey designed to fill knowledge gaps regarding farm management practices, parlour management practices and implemented technologies, milking management practices, somatic cell count (SCC) control strategies, farmer demographics and attitudes around SCC management on a sample of Irish dairy farms.

RESULTS

We categorized 376 complete responses by herd size quartile and calving pattern. The average respondent herd was 131 cows with most (82.2%) operating a seasonal calving system. The median monthly bulk tank somatic cell count for seasonal calving systems was 137,000 cells/ml (range 20,000 - 1,269,000 cells/ml), 170,000 cells/ml for split-calving systems (range 46,000 - 644,000 cells/ml) and 186,000 cells/ml for 'other' herds (range 20,000 - 664,000 cells/ml). The most common parlour types were swing-over herringbones (59.1%) and herringbones with recording jars (22.2%). The average number of units across herringbone parlours was 15, 49 in rotary parlours and two boxes on automatic milking system (AMS) farms. The most common parlour technologies were in-parlour feeding systems (84.5%), automatic washers on the bulk tank (72.8%), automatic cluster removers (57.9%), and entrance or exit gates controlled from the parlour pit (52.2%). Veterinary professionals, farming colleagues and processor milk quality advisors were the most commonly utilised sources of advice for SCC management (by 76.9%, 50.0% and 39.2% of respondents respectively).

CONCLUSIONS

In this study, we successfully utilised a national survey to quantify farm management practices, parlour management practices and technology adoption levels, milking management practices, SCC control strategies and farmer demographics on 376 dairy farms in the Republic of Ireland. Rotary and AMS parlours had the most parlour technologies of any parlour type. Technology add-ons were generally less prevalent on farms with smaller herds. Despite finding areas for improvement with regard to frequency of liner changes, glove-wearing practices and engagement with bacteriology of milk samples, we also found evidence of high levels of documentation of mastitis treatments and high use of post-milking teat disinfection. We discovered that Irish dairy farmers are relatively content in their careers but face pressures regarding changes to the legislation around prudent antimicrobial use in their herds.

Antibiotic use in the Northern Irish sheep flock: What lessons can be learnt from medicine records and farmer attitudes to improve stewardship of these essential medicines?

Stewardship of antibiotics used in livestock production has come under increasing scrutiny, from both the animal welfare point of view and due to concerns that antibiotic use in livestock may pose a risk to human health through selection pressure to drive development of antibiotic resistant strains of bacteria. Despite this concern, however, antibiotic consumption in the sheep sector is currently poorly described. This study determines the range and quantities of antibiotics used in the Northern Irish (NI) sheep flock as well as exploring drivers for their use. A mixed-methods approach was utilised, with an anonymous online scoping survey, analysis of the medicine records from 52 NI sheep farms and semi-structured interviews undertaken with 27 farmers. Eighteen farmers contributed both records and participated in interviews. Veterinary medicine records were derived from two sources: on-farm medicine books (seven) or veterinary practice sales data (51). As six of these farmers provided information from both sources a total of 52 unique farms participated. Overall, antibiotic use in sheep on the 52 farms sampled was low, with a median value of 11.35 mgPCU-1 (mean 13.63 mgPCU-1, sd 10.7; range 0-45.29 mgPCU-1), with all farms below 50 mgkg-1. Critically important antibiotics accounted for 0.21% of all antibiotics purchased. Lameness was the main driver of antibiotic use identified by this study. Others included a range of prophylactic treatments such as oral antibiotics to prevent watery mouth, injectable antibiotics to prevent abortion and following assisted lambing. Farmers acknowledged some of these uses had become habitual over time. The veterinary medicine sales records demonstrated significant sales of antibiotics not authorised for use in sheep, on an ongoing, rather than case-by-case, basis. Farmers were positive about their veterinarian's ability and knowledge to improve flock welfare and productivity, but were unwilling to pay for this advice. However, veterinarians may have facilitated weak medicine stewardship through a failure to adequately challenge farmers seeking antibiotics. Farmers did not maintain accurate or up-to-date on farm medicine or production records in the majority of cases. Despite this lack of on-farm recording, veterinary sales records can be studied in consultation with farmers to provide veterinarians with a farm-specific insight into antibiotic use and related attitudes and behaviours. Farmers and veterinarians can then identify areas and behaviours to target collaboratively, improving antibiotic and wider medicine stewardship, whilst simultaneously improving flock health and productivity.

A qualitative analysis of the unwritten rules influencing antibiotic prescribing practices among French poultry veterinarians

Background

It is now recognized that a better understanding of prescriber behaviour is needed to improve antimicrobial stewardship programmes. Most studies conducted in the livestock sector have focused on farmers' perspectives, while the prescribing habits of veterinarians have remained overlooked.

Objective

Our study explored the psychosocial determinants associated with antibiotic prescribing practices in the French poultry sector by analysing the informal norms and unwritten rules that influence veterinarians' prescribing decisions.

Methods

A qualitative study was conducted in four French regions in February 2021. Using the biographical narrative interpretive method, semi-structured interviews were conducted with 16 poultry veterinarians with varying professional experience. Three main themes were retained for data analysis: (i) compliance with and deviations from prescribing recommendations, (ii) the influence of fellow veterinarians on antibiotic decisions and (iii) the key role of veterinary corporate groups.

Results

When prescribing antibiotics, junior veterinarians were strongly influenced by senior veterinarians who acted as role models driving clinical practices. Prescribing habits were shared through peer networks in which veterinarians participated throughout their careers. Finally, veterinary corporate groups helped to shape veterinarians' prescribing habits by promoting existing guidelines and even producing in-house recommendations.

Conclusions

We show that, in parallel with official guidelines, prescribing habits circulate among veterinarians and are shared in professional circles. Therefore, antimicrobial stewardship interventions should focus not only on official guidelines and communication channels, but also unwritten professional rules and organizations influencing veterinarians' prescribing practices.

Participatory identification of the causes of antimicrobial use and how they may vary according to differences in sector structure: The case of the Flemish pork and veal sectors

The increasing threat of antimicrobial resistance (AMR) to human health has prompted many countries to adopt national action plans to reduce antimicrobial use (AMU) in farm animals. To achieve this goal, it is necessary to gain a deeper understanding of the factors driving AMU in farm animals. While previous research has focused on gaining a better understanding of AMU from the perspective of farmers and veterinarians, less emphasis has been placed on examining the systemic and contextual factors that influence AMU from multiple viewpoints within the food supply chain. To this end, this paper describes a participatory approach involving multiple stakeholders from two distinct livestock sectors to identify the underlying drivers of AMU and explore their case-specificity. For each sector, we identified causes of AMU during four online focus groups, by co-creating a "problem tree", which resulted in the identification of over 50 technical, economic, regulatory, and sociocultural causes per sector and exploration of causal links. Following this, we analysed the focus group discussion through a content analysis and clustered causes of AMU that were related into 17 categories (i.e. main drivers of AMU), that we then classified as drivers of AMU at sector level or drivers of AMU at farm level. Finally, we compared the two sectors by assessing whether the generated categories (i.e. main drivers for AMU) had been discussed for both sectors and, if so, whether they involved the same causes and had the same implications. Through our analysis, we gained a better understanding of several main drivers of AMU at sector level, that result from systemic and/or contextual causes. As these cannot always be addressed by farmers and/or their veterinarian, we suggest that interventions should also target other actors related to these causes or consider them to help implement certain strategies. Furthermore, based on the results of our comparative analysis, we suggest that systemic structural differences, such as size and level of supply chain integration/fragmentation, may lead to differences in how animal health management is approached. This in turn may influence AMU's decision-making and the effectiveness of interventions, if they are generic and not tailored to the specificities of the sector.

Bioinspired silver nanoparticle-based nanocomposites for effective control of plant pathogens: A review

Plant pathogens, including bacteria, fungi, and viruses, pose significant challenges to the farming community due to their extensive diversity, the rapidly evolving phenomenon of multi-drug resistance (MDR), and the limited availability of effective control measures. Amid mounting global pressure, particularly from the World Health Organization, to limit the use of antibiotics in agriculture and livestock management, there is increasing consideration of engineered nanomaterials (ENMs) as promising alternatives for antimicrobial applications. Studies focusing on the application of ENMs in the fight against MDR pathogens are receiving increasing attention, driven by significant losses in agriculture and critical knowledge gaps in this crucial field. In this review, we explore the potential contributions of silver nanoparticles (AgNPs) and their nanocomposites in combating plant diseases, within the emerging interdisciplinary arena of nano-phytopathology. AgNPs and their nanocomposites are increasingly acknowledged as promising countermeasures against plant pathogens, owing to their unique physicochemical characteristics and inherent antimicrobial properties. This review explores recent advancements in engineered nanocomposites, highlights their diverse mechanisms for pathogen control, and draws attention to their potential in antibacterial, antifungal, and antiviral applications. In the discussion, we briefly address three crucial dimensions of combating plant pathogens: green synthesis approaches, toxicity-environmental concerns, and factors influencing antimicrobial efficacy. Finally, we outline recent advancements, existing challenges, and prospects in scholarly research to facilitate the integration of nanotechnology across interdisciplinary fields for more effective treatment and prevention of plant diseases.

Understanding Knowledge and Attitude of Farmers towards Antibiotic Use and Antimicrobial Resistance in Jhunjhunu District, Rajasthan India

The misuse of antibiotics in veterinary practices by farmers is harming livestock production and food safety and leading to the rise of antibiotic resistance (AMR). This can also transfer resistant bacteria from animals to humans, posing a serious public health threat. However, we have not paid enough attention to understanding how farmers behave in this regard. Our study aims to explore farmers' behaviors and identify the factors that influence their choices. To conduct this study, we used a questionnaire with 40 questions and surveyed 208 farmers in Jhunjhunu district, Rajasthan. We analyzed the data using SPSS. Here are the key findings: About 58.3% of the farmers have some awareness of antibiotics, and 49.5% are aware of antimicrobial resistance (AMR). Notably, as the level of education increases, so does awareness of antibiotics. Unfortunately, 63.9% of the farmers are not aware of the withdrawal time, and 64% have no idea about the presence of antibiotic residues during this period. Around 75% of farmers vaccinate their animals, but approximately 56.9% of individuals have never undergone an antibiotic sensitivity test (ABST) for milk. Around 48.6% of farmers are unaware of government testing centers. Several factors hinder farmers from implementing proper animal management practices, such as the high fees of veterinarians. When their animals become sick, their first choice is home remedies, followed by using old prescriptions. Additionally, 63.9% stop treatment once the animal looks better. A significant portion (83.8%) of farmers rely on local pharmacists for medicine. It has been determined that there is no significant correlation between education, experience, age, and the level of awareness concerning withdrawal periods, the existence of government antibiotic sensitivity test (ABST) centers, and entities responsible for sending samples for ABST. In our qualitative analysis, focus groups identified significant barriers to following best farm practices and spreading awareness about AMR. These findings suggest that addressing AMR in livestock requires a comprehensive approach. This should include targeted education and awareness programs for farmers, as well as improved access to veterinary services.

Factors influencing Scottish dairy farmers' antimicrobial usage, knowledge and attitude towards antimicrobial resistance

Understanding how farmers use antimicrobials and their awareness and beliefs about antimicrobial resistance (AMR) is essential to improve antimicrobial usage (AMU) practices and combat AMR on dairy farms. A cross-sectional online survey was carried out to identify the factors affecting attitudes, knowledge and behaviour of Scottish dairy producers regarding prudent AMU and the emergence of AMR in livestock. The survey was designed based on the earlier findings of two focus groups and was disseminated online via multiple methods (e.g., social media; farming press). Participation was voluntary and answers were obtained from 61 respondents (7.3% of the total population of Scottish dairy farmers). Logistic and ordinal regression analyses were performed to identify predictors for farmers' level of knowledge about antimicrobials and AMR, AMU behaviour and attitudes towards AMR mitigation. Associations were described with odds ratios (OR) and the associated 95% confidence intervals (95% CI). Farmers were more likely to have better knowledge of antimicrobials and AMR if they had undertaken a university degree (OR = 28.28, P < 0.001), worked with mixed livestock (dairy plus sheep/beef) (OR = 4.82, P < 0.05), and trusted only veterinarians' information about responsible AMU (OR = 4.42, P < 0.05). In the survey disease scenarios, younger farmers were less likely to be classed as low antimicrobial users (OR = 0.18, P < 0.05) compared to older farmers. Respondents working on larger herds were also less likely to be low antimicrobial users compared to those working on smaller herds (OR = 0.12, P < 0.01). Conversely, farmers who did not consider economic factors (e.g., cost and withdrawal period) in antimicrobial choice were more likely to be classed as low antimicrobial users (OR = 6.17, P < 0.01). Respondents were more likely to show positive attitudes towards AMR mitigation if they worked in larger (OR = 4.67, P < 0.05) or organic dairy farms (OR = 18.35, P < 0.05). These results suggest that several practices, social, demographic, and economic factors influence dairy farmers' perception and awareness of AMR and AMU. Efforts should be made to consider these variables when developing strategies to improve AMU in dairy farming. Veterinarians and advisors should focus AMU training and AMR awareness-raising activities towards younger, less experienced farmers as well as those with a lower educational qualification (high school vs. university degree). This study can inform the development of targeted educational initiatives to encourage responsible AMU on dairy farms.

Education and Awareness on Antimicrobial Resistance in the WHO African Region: A Systematic Review

This review documents the status of AMR education and awareness in the WHO African region, as well as specific initiatives by its member states in implementing education and awareness interventions, as a strategic objective of the Global Action Plan on AMR, i.e., improve knowledge and understanding on AMR through effective communication, education, and training. A systematic search was conducted in Google Scholar, PubMed, and African Journals Online Library according to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines, for articles published in English. Retrieval and screening of articles was performed using a structured search protocol following a pre-set inclusion/exclusion criterion. Eighty-five published articles reporting 92 different studies from 19 Member States met inclusion criteria and were included in the final qualitative synthesis. Nigeria (21) and Ethiopia (16) had most of the studies, while the rest were distributed across the remaining 17 Member States. The majority of the articles were on knowledge, attitude, and practices with regard to AMR and antimicrobial use and most of them documented a general lack and suboptimal knowledge, poor attitude and practices, and widespread self-medication. This review shows low levels of knowledge of AMR coupled with extensive misuse of antimicrobial medicines by different target audiences. These findings underscore the urgent need for enhanced and context-specific educational and positive behavioural change interventions.

An agent-based model for collaborative learning to combat antimicrobial resistance: proof of concept based on broiler production in Senegal

Antimicrobial resistance (AMR) is a substantial global One Health problem. This paper reports on initial, proof-of-concept development of an agent-based model (ABM) as part of wider modelling efforts to support collaborations between groups interested in policy development for animal health and food systems. The model simulates AMR in poultry production in Senegal. It simultaneously addresses current policy issues, builds on existing modelling in the domain and describes AMR in the broiler chicken production cycle as seen by producers and veterinarians. This enables implementation and assessment of producer antimicrobial use and infection prevention and control strategies in terms of immediate economic incentives, potentially helping to advance conversations by addressing national policy priorities. Our model is presented as a flexible tool with promise for extension as part of AMR policy development in Senegal and West Africa, using participatory approaches. This work indicates that ABM can potentially play a useful role in fostering counter-AMR initiatives driven by food system actor behaviour in lower- and middle-income countries more generally.

A mixed-method survey to understand the role of dog welfare organisations in Ireland, including reported challenges and potential solutions

BACKGROUND

This novel study forms part of a larger research programme seeking an improved understanding of aspects of the owned dog population in Ireland. Dog welfare organisations (DWOs) in Ireland are recognised as an instrumental pillar of the animal welfare sector with some receiving substantial public funding. We conducted a survey of DWOs in Ireland (n = 39) to gain a better understanding of their role and function, including their policies and procedures and the rehoming of dogs to other regions. In addition, we wanted to get a better understanding of the challenges experienced by DWOs in fulfilling their role and their perspectives on potential solutions to these challenges. The survey questions consisted of closed and open-ended items. Closed items were analysed quantitively; open-ended items were analysed thematically.

RESULTS

Most DWOs (> 80%) had written protocols for important welfare actions including rehoming procedures, assessment of owner suitability and euthanasia. DWOs sent dogs to Northern Ireland (13%), Great Britain (38.5%) and to other countries outside the United Kingdom (36%, including Germany, Sweden, Italy, the Netherlands and Czechia). Reported challenges included a general lack of funding, limited public awareness of the importance of dog welfare and insufficient capacity to handle dog numbers. To address these challenges, the DWOs highlighted the potential contribution of subsidised programmes and access to resources to educate potential owners. In a further qualitative evaluation to capture perceptions of appropriate solutions by DWOs, several themes emerged, relating to legislation, education, an overwhelmed workforce, and funding.

CONCLUSIONS

This study provides important insights into the roles and functions of DWOs and challenges they experience in Ireland. It is hoped that the findings from this research will inform future research investigating potential solutions to these challenges as well as the development of policy in Ireland.

Drivers of antimicrobial resistance in layer poultry farming: Evidence from high prevalence of multidrug-resistant Escherichia coli and enterococci in Zambia

Background and Aim

Inappropriate use of antimicrobials exacerbates antimicrobial resistance (AMR) in the poultry sector. Information on factors driving AMR in the layer poultry sector is scarce in Zambia. This study examined the drivers of AMR in the layer poultry sector in the Lusaka and Copperbelt Provinces of Zambia.

Materials and Methods

This cross-sectional study employed a structured questionnaire in 77 layer poultry farms in the provinces of Lusaka and Copperbelt, Zambia, from September 2020 to April 2021. Data analysis was conducted using Stata version 16.1. Antimicrobial resistance was defined as the presence of multidrug resistance (MDR) isolates. Multivariable regression analysis was used to identify drivers of AMR.

Results

In total, 365 samples were collected, from which 339 (92.9%) Escherichia coli and 308 (84.4%) Enterococcus spp. were isolated. Multidrug resistance was identified in 39% of the E. coli and 86% of the Enterococcus spp. The overall prevalence of AMR in layer poultry farms was 51.7% (95% confidence interval [CI]: 40.3%-63.5%). Large-scale farmers (Adjusted odds ratio [AOR] = 0.20, 95% CI: 0.04%-0.99%) than small-scale and farmers who were aware of AMR than those who were unaware (AOR = 0.26, 95% CI: 0.08%-0.86%) were less likely to experience AMR problems.

Conclusion

This study found a high prevalence of AMR in layer poultry farming linked to the type of farm management practices and lack of AMR awareness. Evidence of high MDR in our study is of public health concern and requires urgent attention. Educational interventions must increase AMR awareness, especially among small- and medium-scale poultry farmers.

Antimicrobial Resistance (AMR)

Antimicrobial resistance (AMR) has now emerged as a chronic public health problem globally, with the forecast of 10 million deaths per year globally by 2050. AMR occurs when viruses, bacteria, fungi and parasites do not respond to antimicrobial treatments in humans and animals, thus allowing the survival of the microorganism within the host. The prominent cause contributing to the current crisis remains to be the overuse and misuse of antimicrobials, particularly the inappropriate usage of antibiotics, increasing the global burden of antimicrobial resistance. The global consumption and usage of antibiotics are therefore closely monitored at all times. This review provides a current overview of the implications of strategies used by international governmental organisations, including the UN's 17 Sustainable Development Goals (SDGs), to address the problem of antibiotic resistance, as well as the "One Health Approach," a system incorporating a multidisciplinary effort to achieve the best possible health outcome by acknowledging the clear connections between humans, animals and their shared environment. The importance of public awareness and health literacy of lay audiences still needs to be further emphasised as part of global and local action plans. Antimicrobial resistance continues to be a major global public health dilemma of the 21st century. Already this topic is receiving substantial political input from the G7 countries and continues to be on the agenda of numerous political conferences. The consequences of failure to adequately address AMR are profound, with estimations of a return to the pre-antibiotic era, where everyday infections relating to childbirth, surgery and open fractured limbs could be potentially life-threatening. AMR itself represents a microcosm of factors, including social anthropology, civil unrest/war, diasporas, ethnic displacement, political systems, healthcare, economics, societal behaviour both at a population and individual level, health literacy, geoclimatic events, global travel and pharmaceutical innovation and investment, thus finding a solution that adequately addresses AMR and which helps stem further AMR emergence is complicated. Success will involve individuals, communities and nations all working together to ensure that the world continues to possess a sufficient armamentarium of effective antimicrobials that will sustain human and animal health, both now and in the future.

Immobilization of Natural Antimicrobial Compounds on Food-Grade Supports as a New Strategy to Preserve Fruit-Derived Foods

The use of natural antimicrobials in the food industry is being proposed as an eco-friendly postharvest technology to preserve fruit-derived foods. In this context, this systematic review aims to describe and discuss the application of naturally occurring antimicrobial compounds in the processing of fruit-derived foods by the PRISMA methodology. In a first step, the use of free natural antimicrobials was investigated as an approach to identify the main families of bioactive compounds employed as food preservatives and the current limitations of this dosage form. Then, the use of immobilized antimicrobials, in an innovative dosage form, was studied by distinguishing two main applications: addition to the food matrix as preservatives or use during processing as technological aids. Having identified the different examples of the immobilization of natural antimicrobial compounds on food-grade supports, the mechanisms of immobilization were studied in detail to provide synthesis and characterization guidelines for future developments. Finally, the contribution of this new technology to decarbonization and energy efficiency of the fruit-derived processing sector and circular economy is discussed in this review.

Antimicrobial usage and resistance in scottish dairy herds: a survey of farmers' knowledge, behaviours and attitudes

Antimicrobial resistance (AMR) poses a major threat to global health. Understanding how antimicrobials are used on dairy farms and stakeholder beliefs relating to their use is essential to ensure responsible antimicrobial usage (AMU) to tackle the emergence of AMR. This study explored Scottish dairy farmers' knowledge about the meaning of AMR and antimicrobial activity, behaviour and practices related to farm AMU and attitudes towards AMR mitigation. An online survey was designed based on the findings of two focus groups and was completed by 61 respondents (7.3% of the total population of Scottish dairy farmers). Knowledge of antimicrobials and AMR was variable, and almost half of the participants believed that antimicrobials could have anti-inflammatory or analgesic activity. Veterinarians' opinions and advice about AMU were ranked significantly more important than other social referents or advisors. The majority of farmers (90%) reported having implemented practices to reduce reliance on antimicrobials (e.g., selective dry cow therapy, AMU treatment protocols) and having reduced farm AMU over recent years. Feeding waste milk to calves is still widespread, being reported by up to 30% of respondents. The main factors described to hinder responsible farm AMU were limited facilities (e.g., lack of isolation pens for sick animals) and knowledge of appropriate AMU recommendations, followed by time and financial constraints. Most farmers (89%) agreed that it is important to reduce AMU on dairy farms, but fewer (52%) acknowledged that AMU on UK dairy farms is currently too high, suggesting a mismatch between their intention to reduce antimicrobials and AMU behaviour. These results indicate that dairy farmers are aware of AMR, and their self-reported farm AMU has been reduced. However, some do not clearly comprehend the activity of antimicrobials and their correct usage. More work is needed to improve dairy farmers' knowledge of appropriate AMU and intentions to combat AMR. Farmers would benefit from more regular AMU discussions and advice from herd veterinarians, as they were described as highly trusted information resources. Training on how to reduce AMU should involve all farm staff administering antimicrobials and should be tailored to farm-specific barriers, such as limited facilities and workforce shortages.

Factors influencing dairy farmers' antibiotic use: An application of the COM-B model

In dairy farming, mastitis treatment is the most common reason for antimicrobial use. The overuse or misuse of antibiotics in agriculture has been associated with the development and spread of antimicrobial resistance (AMR). Traditionally, blanket dry cow therapy (BDCT), in which all cows receive antibiotic treatment, was used prophylactically to prevent and manage disease spread. In recent years, there has been a move toward selective dry cow therapy (SDCT), in which only clinically infected cows are treated with antibiotics. This study aimed to explore farmer attitudes toward antibiotic use (ABU), using the COM-B (Capability-Opportunity-Motivation-Behavior) model as a framework, to identify predictors of changing behavior toward SDCT and suggest interventions to encourage its uptake. Participant farmers (n = 240) were surveyed online between March and July 2021. Five items were found to be significant predictors of farmers having stopped BDCT: (1) having lower knowledge of AMR, (2) greater awareness of AMR and ABU (Capability), (3) feeling social pressure to reduce ABU (Opportunity), and (4) having greater professional identity, and (5) having positive emotions associated with stopping BDCT (Motivation). Direct logistic regression found that these 5 factors explained between 22 and 34.1% of the variance in making changes to BDCT practices. Additionally, objective knowledge was not correlated with current positive antibiotic practices, and farmers often perceived their antibiotic practices as more responsible than they actually were. A multifaceted approach, encompassing each of the predictors highlighted, should be taken to encourage farmer behavior change in relation to stopping BDCT. Additionally, as farmers' perceptions of their own behaviors may not align with their actual practices, awareness raising of what constitutes "responsible" behavior should be targeted at dairy farmers to motivate them to take action and adopt more responsible antibiotic practices.

Barriers and facilitators to implementing a new regulation restricting antimicrobial use in dairy production in Québec, Canada: A qualitative study

With the emergence of antimicrobial resistance (AMR), many countries are implementing restrictive regulations to reduce antimicrobial use (AMU) in animal production. Although these measures are effective at the national level, their implementation may generate challenges for producers and veterinarians. The objective of this study was to explore the barriers and facilitators of implementing a new regulation restricting the use of antimicrobials of very high importance for human health in the dairy production sector in the province of Québec, Canada. Individual interviews were conducted with fifteen veterinarians and twenty-seven dairy producers. Thematic analysis was performed based on the COM-B model of behavior change (capability-opportunity-motivation-behavior). Our results indicated that the lack of availability of alternative treatments, the long delays related to diagnostic tests and the fear of economic consequences were major barriers to the implementation of the regulation. A small number of producers also perceived that the regulation negatively impacted the health and wellbeing of their animals. Additionally, participants acknowledged the importance of early education and training to better understand the purpose of the regulation and increase its acceptability. Lastly, most participants reported that they had not only reduced their use of antimicrobials of very high importance for human health following the regulation, but they had also increased preventive practices on their farm. This study reveals that the implementation of restrictive regulations to reduce AMU in animal production can lead to multiple challenges in practice. Our results highlight the need for better communication and training of producers and veterinarians before and during the implementation of similar regulations in the future and underline the importance of measuring the direct and indirect impacts of those regulations on productivity and on animal health and wellbeing.

Exploring veterinarians' behaviour relating to antibiotic use stewardship on Irish dairy farms using the COM-B model of behaviour change

Employing a theoretical model of human behaviour (COMB), the current study explores the factors influencing veterinarians' engagement with antibiotic use stewardship on Irish dairy farms. One-to-one semi structured interviews were carried out by telephone with 12 veterinarians whose daily work focused on dairy cattle. A thematic analysis approach was undertaken. The identified themes and sub-themes were then mapped to the COM-B model. This study identified challenges faced by veterinarians when trying to prescribe responsibly which included lack of training to encourage farmer behaviour change, issues with laboratory testing, pressures from farmers to prescribe antimicrobials, concern for animal welfare and farmers going elsewhere for prescriptions. Having a good knowledge of AMR, peers as an advice source, potential financial benefits for farmers as a result of reduced antimicrobial costs and accepting a shared responsibility for AMR, facilitate veterinarians in their role as antimicrobial stewards. The barriers and facilitators identified as influencing veterinarians' capability, opportunity and motivation to responsibly prescribe antimicrobials formed the basis for a number of practical recommendations which should be considered by advisory and policy making teams. Recommendations include; continuous training for veterinarians on AMR and alternatives to overcome the barriers faced when trying to promote reduced AMU, veterinarian peer support groups to improve confidence in their knowledge and decision making to minimise the effect of client pressures/expectations, setting up collaborative farmer and veterinarian working groups to promote a transparent working relationship and the development of affordable and efficient diagnostic and susceptibility testing.

A review of new emerging livestock-associated methicillin-resistant Staphylococcus aureus from pig farms

Methicillin-resistant Staphylococcus aureus (MRSA) is a S. aureus strain resistant to β-lactam antibiotics and is often associated with livestock, known as livestock-associated (LA)-MRSA. Using molecular typing with multi-locus sequence typing, MRSA clones have been classified in pigs, including clonal complex 398. Livestock-associated-methicillin-resistant S. aureus was first discovered in pigs in the Netherlands in 2005. Since then, it has been widely detected in pigs in other countries. Livestock-associated-methicillin-resistant S. aureus can be transmitted from pigs to pigs, pigs to humans (zoonosis), and humans to humans. This transmission is enabled by several risk factors involved in the pig trade, including the use of antibiotics and zinc, the size and type of the herd, and the pig pen management system. Although LA-MRSA has little impact on the pigs' health, it can be transmitted from pig to pig or from pig to human. This is a serious concern as people in direct contact with pigs are highly predisposed to acquiring LA-MRSA infection. The measures to control LA-MRSA spread in pig farms include conducting periodic LA-MRSA screening tests on pigs and avoiding certain antibiotics in pigs. This study aimed to review the emerging LA-MRSA strains in pig farms.

The New Precision Stewards?

The precision health era is likely to reduce and respond to antimicrobial resistance (AMR). Our stewardship and precision efforts share terminology, seeking to deliver the “right drug, at the right dose, at the right time.” Already, rapid diagnostic testing, phylogenetic surveillance, and real-time outbreak response provide just a few examples of molecular advances we dub “precision stewardship.” However, the AMR causal factors range from the molecular to that of global health policy. Mirroring the cross-sectoral nature of AMR science, the research addressing the ethical, legal and social implications (ELSI) of AMR ranges across academic scholarship. As the rise of AMR is accompanied by an escalating sense of its moral and social significance, what is needed is a parallel field of study. In this paper, we offer a gap analysis of this terrain, or an agenda for “the ELSI of precision stewardship.” In the first section, we discuss the accomplishments of a multi-decade U.S. national investment in ELSI research attending to the advances in human genetics. In the next section, we provide an overview of distinct ELSI topics pertinent to AMR. The distinctiveness of an ELSI agenda for precision stewardship suggests new opportunities for collaboration to build the stewardship teams of the future.

Perception of poultry veterinarians on the use of antimicrobials and antimicrobial resistance in egg production

This study aimed to describe the perception of veterinarians who work with commercial laying hens in the state of Rio Grande do Sul, Brazil, regarding the use of antibiotics and their possible impacts on animal, human, and environmental health. A descriptive epidemiological study was carried out through face-to-face or web conferencing interviews with the veterinarians that provide technical assistance at commercial laying hen operations. A standardized and structured questionnaire was developed based on the literature and expert opinion, which contained 1 opened and 40 closed questions. Conventional non-probabilistic sampling was used, based on an initial list of 15 veterinarians registered in the Poultry Production Association of Rio Grande do Sul, followed by the snowball technique. The acquisition of 26 contacts of veterinarians was accomplished, and 16 were interviewed. Through the answers obtained it was possible to verify that the interviewees' understanding regarding both the antibiotic resistance impact and the decision-making about the use of antibiotics seem to be linked to their practical experiences. Besides that, according to the veterinarians, farmers can acquire and administer the antimicrobials on their farms. Moreover, both farm storage and administration of lower doses of antibiotics than the recommended one could be contributing factors to resistant bacteria selection. Furthermore, controversially, the professionals believed that resistant bacteria can be transmitted to humans from eggs, but they said that there are no bacteria in eggs. Therefore, the veterinarians´ practices can be improved considering national and international guidelines on antimicrobial resistance to minimize the development of resistance. Finally, it is expected that the present results will contribute to a more complex discussion about antimicrobial resistance, helping to formulate public policies in the egg production industry.

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): antimicrobial-resistant Staphylococcus aureus in cattle and horses

Staphylococcus aureus (S. aureus) was identified among the most relevant antimicrobial-resistant (AMR) bacteria in the EU for cattle and horses in previous scientific opinions. Thus, it has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on its eligibility to be listed, Annex IV for its categorisation according to disease prevention and control rules as in Article 9, and Article 8 for listing animal species related to the bacterium. The assessment has been performed following a methodology previously published. The outcome is the median of the probability ranges provided by the experts, which indicates whether each criterion is fulfilled (lower bound ≥ 66%) or not (upper bound ≤ 33%), or whether there is uncertainty about fulfilment. Reasoning points are reported for criteria with uncertain outcome. According to the assessment here performed, it is uncertain whether AMR S. aureus can be considered eligible to be listed for Union intervention according to Article 5 of the AHL (60-90% probability). According to the criteria in Annex IV, for the purpose of categorisation related to the level of prevention and control as in Article 9 of the AHL, the AHAW Panel concluded that the bacterium does not meet the criteria in Sections 1, 2 and 4 (Categories A, B and D; 1-5%, 5-10% and 10-33% probability of meeting the criteria, respectively) and the AHAW Panel was uncertain whether it meets the criteria in Sections 3 and 5 (Categories C and E, 33-90% and 60-90% probability of meeting the criteria, respectively). The animal species to be listed for AMR S. aureus according to Article 8 criteria include mainly mammals, birds, reptiles and fish.

Fijian Farmers' Attitude and Knowledge Towards Antimicrobial Use and Antimicrobial Resistance in Livestock Production Systems–A Qualitative Study

Antimicrobial resistance (AMR) is a global health issue affecting humans and livestock. To mitigate AMR risks, responsible use of antimicrobials in livestock production systems have been advocated. Studies have reported patterns of antimicrobial use (AMU) in livestock production systems; however, there is limited information on the drivers of AMU and AMR. Therefore, this study aimed to explore and understand the attitude and knowledge of Fijian livestock farmers on AMU and AMR. Livestock farmers and managers from the Central and Western divisions of Viti Levu, Fiji were recruited using purposive and snowball sampling methods. Face-to-face one-to-one semi-structured qualitative interviews were conducted. Interview questions were informed by the Theory of Planned Behavior (TPB). Interview transcripts were analyzed inductively using reflexive thematic analysis and deductively using the TPB framework. A total of 19 cattle and poultry farmers took part. Our analysis generated four themes: (1) Uninformed use of antimicrobials and unaware of AMR, (2) Safeguarding livestock and generating income source as primary motivators for using antimicrobials (3) Medicine shortage results in hoarding and self-prescribing, and (4) Farm decisions on AMU and livestock management influenced by foreign farmers and veterinarians. Livestock farmers used medicines in livestock production; however, they could not differentiate amongst different types of medicine, including antimicrobials. Antimicrobials were used to prevent diseases in livestock and promote production of food and financial security but without any awareness of the risks of AMR. Additionally, farmers hoarded and self-prescribed medicines. Farmers rationed antimicrobials by not completing the entire course of antibiotics to save them for future use. Based on past experiences, farmers expressed dissatisfaction with the veterinary services provided by the government. They sought help online and from foreign farmers and veterinarians. We propose the need for antimicrobial stewardship (AMS) programmes focused on promoting rational use of antimicrobials and awareness of AMR amongst farmers in the Fijian livestock production systems. These programmes need to consider the anthropological, socio-cultural, economic, and environmental factors driving AMU. Future studies are underway to explore the attitude and knowledge of Fijian veterinarians, para-veterinarians and pharmacists on AMU and AMR to gain a broader systems knowledge to inform the design of AMS programmes.

Awareness of Antimicrobial Resistance and Associated Factors among Layer Poultry Farmers in Zambia: Implications for Surveillance and Antimicrobial Stewardship Programs

Antimicrobial resistance (AMR) is a global public health problem affecting animal and human medicine. Poultry production is among the primary sources of income for many Zambians. However, the increased demand for poultry products has led to a subsequent increase in antimicrobial use. This study assessed the awareness of AMR and associated factors among layer poultry farmers in Zambia. A cross-sectional study was conducted among 77 participants from September 2020 to April 2021. Data was analysed using Stata version 16.1. The overall awareness of AMR among the farmers was 47% (n = 36). The usage of antibiotics in layer poultry production was high at 86% (n = 66). Most antibiotics were accessed from agrovets (31%, n = 24) and pharmacies (21%, n = 16) without prescriptions. Commercial farmers were more likely to be aware of AMR compared to medium-scale farmers (OR = 14.07, 95% CI: 2.09–94.70), as were farmers who used prescriptions to access antibiotics compared to those who did not (OR = 99.66, 95% CI: 7.14–1391.65), and farmers who did not treat market-ready birds with antibiotics compared to those who did (OR = 41.92, 95% CI: 1.26–1396.36). The awareness of AMR among some layer farmers was low. Therefore, policies that promote the rational use of antibiotics need to be implemented together with heightened surveillance activities aimed at curbing AMR.

Assessing Knowledge, Beliefs, and Behaviors around Antibiotic Usage and Antibiotic Resistance among UK Veterinary Students: A Multi-Site, Cross-Sectional Survey

Antimicrobial resistance (AMR) is a profound threat to human and animal health. Antimicrobial prescribing behaviours are influenced by psychological factors such as knowledge, beliefs, and emotions. As future antimicrobial prescribers, it is important to understand beliefs about AMR and stewardship among veterinary (vet) students. This cross-sectional online survey assessed vet students' self-reported behavior, knowledge, and beliefs in specific relation to antibiotic resistance (ABR) and antibiotic usage. Participants were early years (first- and second-year; n = 460) and later-years (third- and fourth-year; n = 113) undergraduate vet students from three UK universities. Self-reported antibiotic-related behaviors were responsible among most students. Knowledge about ABR and stewardship was moderate among early years students and good among later years students. Vet students typically believed that vets had less responsibility for both causing and preventing ABR than other groups (animal owners, human medics, and the public). This study offers evidence that vet students (along with other groups) tend to lay greater responsibility for ABR/AMR outside of their own profession, which may impact their future prescribing behaviors. It is vital that AMR and antimicrobial stewardship are embedded across veterinary curricula, and that the One Health nature of the challenge posed by AMR is emphasized to encourage shared responsibility across all stakeholder groups, thereby helping to reduce 'other-blaming' for AMR.