Perceptions of Tennessee cattle producers regarding the Veterinary Feed Directive

Functional evaluation of Bacillus licheniformis PF9 for its potential in controlling enterotoxigenic Escherichia coli in weaned piglets

During the bacterial selection, isolate PF9 demonstrated tolerance to low pH and high bile salt and an ability to extend the lifespan of Caenorhabditis elegans infected with enterotoxigenic Escherichia coli (ETEC; P < 0.05). Thirty-two weaned piglets susceptible to ETEC F4 were randomly allocated to four treatments as follows: 1) non-challenged negative control group (NNC; basal diet and piglets gavaged with phosphate-buffered saline), 2) negative control group (NC; basal diet and piglets challenged with ETEC F4, 3 × 107 CFU per pig), 3) positive control (PC; basal diet + 80 mg·kg-1 of avilamycin and piglets challenged with ETEC F4), and 4) probiotic candidate (PF9; control basal diet + 2.5 × 109 CFU·kg-1 diet of B. licheniformis PF9 and piglets challenged with ETEC F4). The infection of ETEC F4 decreased average daily gain and gain:feed in the NC group when compared to the NNC group (P < 0.05). The inoculation of ETEC F4 induced severe diarrhea at 3 h postinoculum (hpi), 36, 40 hpi in the NC group when compared to the NNC group (P < 0.05). The supplementation of B. licheniformis PF9 significantly relieved diarrhea severity at 3 hpi when compared to the NC group (P < 0.05). The inoculation of ETEC F4 reduced duodenal, jejunal, and ileal villus height (VH) in the NC group when compared to the NNC group. A significant (P < 0.05) decrease was detected in the duodenal VH in the PC and NNC groups. Moreover, the NNC group had a reduced relative mRNA level of Na+-glucose cotransporter 1 (SGLT1) when compared to the NC group (P < 0.05). Compared to the NC and NNC groups, the supplementation of B. licheniformis PF9 increased the relative mRNA levels of aminopeptidase N, occludin, zonula occludens-1, and SGLT1 (P < 0.05). The supplementation of B. licheniformis PF9 also significantly increased the relative mRNA level of excitatory amino acid transporter 1 when compared to the NC group (P < 0.05). Piglets supplemented with B. licheniformis PF9 showed lower relative abundance of Bacteroidetes in the colon than piglets from the NNC group (P < 0.05). The NNC group had a higher relative abundance of Firmicutes in the ileum than all the challenged piglets (P < 0.05); however, a lower relative abundance of Proteobacteria in the ileum and colon was observed in the NC group (P < 0.05). This study provides evidence that B. licheniformis PF9 has the potential to improve the gut health of piglets under challenging conditions.

Livestock health and disease economics: a scoping review of selected literature

Animal diseases in production and subsistence environments have the potential to negatively affect consumers, producers, and economies as a whole. A growing global demand for animal sourced food requires safe and efficient production systems. Understanding the burden of animal disease and the distribution of burden throughout a value chain informs policy that promotes safe consumption and efficient markets, as well as providing more effective pathways for investment. This paper surveys existing knowledge on the burden of animal disease across economic categories of production, prevention and treatment, animal welfare, and trade and regulation. Our scoping review covers 192 papers across peer-reviewed journals and reports published by organizations. We find there exists a gap in knowledge in evaluating what the global burdens of animal diseases are and how these burdens are distributed in value chains. We also point to a need for creating an analytical framework based on established methods that guides future evaluation of animal disease burden, which will provide improved access to information on animal health impacts.

Invited review: Qualitative research in dairy science-A narrative review

The use of qualitative research in dairy science has increased considerably in recent years, providing the opportunity to inform research and practice. This review aims to enhance the accessibility of qualitative research among a range of audiences and specifically: (1) provide an overview of what qualitative research is and the value it can bring to scientific inquiries in the dairy context, (2) illustrate the emergence of qualitative dairy science research in the past 15 to 20 years, (3) outline the role of the researcher and key philosophical assumptions underlying qualitative research, (4) describe qualitative research approaches and methods used in dairy science research, and (5) highlight key aspects of qualitative inquiry used to ensure research trustworthiness. Qualitative approaches in dairy science enable researchers to understand myriad topics including stakeholder relationships, decision-making, and behaviors regarding dairy cattle management, animal welfare, and disease prevention and control measures. Approaches that were used often for qualitative data collection were individual interviews and focus groups, and variations of thematic analysis were common analytical frameworks. To assess public values, attitudes, and perceptions, mixed methods questionnaires that combined quantitative data with qualitative data from open-ended questions were used regularly. Although still used infrequently, action research and participatory approaches have the potential to bridge the research-implementation gap by facilitating group-based learning and on-farm changes. Some publications described the philosophical assumptions inherent to qualitative research, and many authors included reflexivity and positionality statements. Although a comprehensive description of strategies to meet trustworthiness criteria for qualitative research was uncommon, many publications mentioned certain aspects of trustworthiness, such as member checking, researcher triangulation, and the recording of reflexive notes. Qualitative research has been used to deepen our understanding of phenomena relevant to the dairy sector and has opened the door for a broad array of new opportunities. In addition to having merit on its own, qualitative research can guide, inform, and expand on quantitative research, and an understanding of the core pillars of qualitative research can foster interdisciplinary collaborations.

Regulations on the Use of Antibiotics in Livestock Production in South America: A Comparative Literature Analysis

As a global health problem, antimicrobial resistance (AMR) crosses national borders, leading UN (United Nations) multilateral agencies to call for all countries to improve the stewardship of antibiotics in humans and animals. South American countries have changed their regulations regarding antibiotic use in livestock production. This literature review examines how far the five largest meat-producing countries in South America (Argentina, Brazil, Chile, Colombia, and Uruguay) have come in terms of the relevant legislation. Rules on market entry (marketing authorization and official distribution systems) are already set in all countries examined. Four countries do not allow growth promoters based on critically important antibiotics, and countries have also begun to set guidelines and minimum welfare and biosecurity requirements to reduce the therapeutic demand for antibiotics. Nonetheless, there are aspects related to the distribution, use, and disposal of antibiotics that need to be developed further. In conclusion, legislation in South American countries is moving towards the goals set by UN multilateral agencies, but more can be done. Differences between countries' rules and the gold standards set by the World Organization for Animal Health (OIE), World Health Organization (WHO), and Food and Agriculture Organization of the United Nations (FAO) reveal possible adaptations to the countries' realities. Further studies must examine compliance with the legislation already set and investigate other tools that can be used alongside legislation as a driving force to change stakeholder behaviour.

Tetracycline, Sulfonamide, and Erythromycin Residues in Beef, Eggs, and Honey Sold as "Antibiotic-Free" Products in East Tennessee (USA) Farmers' Markets

Foods that contain antibiotic residues have potential adverse health effects on consumers and provide selective pressure for the threat of antimicrobial resistance (AMR). This study's objective was to measure tetracycline, sulfonamide, and erythromycin residues in beef, eggs, and honey sold as "antibiotic-free" at farmers' markets in East Tennessee (East TN) in the United States (U.S.). Between July and September 2020, 36 "antibiotic-free" food products (9 beef, 18 egg, and 9 honey products) were purchased from East TN farmers' markets and tested for tetracycline, sulfonamide, and erythromycin residues using competitive enzyme-linked immunosorbent assays (cELISA). All beef, egg, and honey products had tetracycline residue; the median concentrations were 51.75, 30.25, and 77.86 µg/kg, respectively. Sulfonamide residue was present in every sample of beef. Of 18 eggs, 11 eggs had detectable sulfonamide residue; the median concentrations were 3.50 and 1.22 µg/kg in beef and eggs, respectively. Each sample of beef and honey contained erythromycin residue; the median concentrations were 3.67 and 0.68 µg/kg, respectively. Overall, the median concentrations of tetracycline, sulfonamide, and erythromycin residues were below the maximum residue levels (MRLs) set in the U.S. for beef and eggs. Thus, the beef and eggs sold as "antibiotic-free" in East TN farmers' markets can be considered safe for consumption. Safety determination for honey could not be made because MRLs have not been set for honey in the U.S. Because these residues should not be expected in "antibiotic-free" food products, it is important to further investigate the potential sources of these residues in these products.

Assessment of the knowledge and behavior of backyard and small-scale producers in California regarding disease prevention, biosecurity practices and antibiotics use

The number and popularity of backyard poultry and livestock farming have rapidly increased in California as well as other states in the United States following consumers' preference for local and organic products in the last few years. This study aimed to investigate current on-farm management and farmers' understanding of Veterinary Feed Directive (VFD) and California Senate Bill (SB) 27 implications for disease prevention, biosecurity procedures, and antimicrobial use in small-scale and backyard farms in California. The survey consisted of 38 questions. The responses of 242 backyard and small-scale livestock owners were investigated in this study. Descriptive statistics summarized survey responses, and multivariable logistic regression evaluated the association of antibiotics purchase and use, and the impact of VFD and SB27 on antibiotic use with demographics and on-farm management. Backyard and small-scale farmers in California mostly raised chickens or small ruminants with small herd sizes kept for personal use. Antibiotics were generally used for individual treatment of a sick animal with the guidance of a veterinarian. VFD and SB27 implementation promoted the judicious use of antibiotics, specifically, by enhancing the relationship between backyard and small-scale farmers with veterinarians and treating fewer animals with antibiotics under veterinary oversight. Therefore, better access to veterinary service in backyard and small-scale farms will improve the farmer's knowledge of good husbandry practices with judicious antimicrobial use in livestock and finally contribute to reducing the risk of antimicrobial resistance in California.

Effect of Changes in Veterinary Feed Directive Regulations on Violative Antibiotic Residues in the Tissue of Food Animals from the Inspector-Generated Sampling in the United States

The presence of antibiotic residues in the tissue of food animals is a growing concern due to the adverse health effects that they can cause in humans, such as antibiotic resistance bacteria. An inspector-generated sampling (IGS) dataset from the United States National Residue Surveillance Program, collected between 2014 and 2019, was analyzed to investigate the association of changes in the veterinary feed directive (VFD) regulations on the detection of violative penicillin, tetracycline, sulfonamide, desfuroylceftiofur, tilmicosin, and florfenicol, residues in the tissue of food animals. Multivariable logistic regression models were used for analysis. While the animal production class was significantly associated with residue violations for tetracycline, having a sample collection date after the implementation of change in VFD regulations was not. However, the odds of detecting violative sulfonamide and penicillin residues in the tissue of food animals following the implementation of the change in VFD regulations were 36% and 24% lower than those collected before the implementation of the change in VFD regulations period, respectively, irrespective of animal production class. Violative desfuroylceftiofur, tilmicosin, and florfenicol residues in the tissue of food animals were not significantly associated with the implementation of changes in the VFD regulations. Further investigation of the factors that influence the presence of violative antibiotic residues in the tissue of food animals following the change in VFD regulations would lend clarity to this critical issue.

Emotive Themes from Tennessee Cattle Producers Regarding Responsible Antibiotic Use

To improve judicious antimicrobial use (AMU) in food animals in the United States, all feed additives that were medically important antimicrobials were moved from over the counter to Veterinary Feed Directive in 2017. This action required a change in behavior of producers’ AMU practices. Because emotions are important aspects of behavior, several behavioral interventions have targeted people’s emotions as means of effecting change. Hence, understanding and incorporating the emotional experiences of producers towards current AMU practices can be a starting point to making future behavioral changes that could reduce the emergence of antimicrobial resistance challenge. Between June 2017 and March 2018, seven focus group meetings of Tennessee (TN) beef and dairy cattle producers were conducted to evaluate producers’ emotional views regarding responsible AMU in TN cattle. Sixty-two TN cattle producers participated and emotively expressed the following: (1) deep connections to animals in ways that improve animal and public health; (2) pride in their quality of products; (3) distress that consumers misconceive their AMU practices as indiscriminate; and (4) recommended that producers be more transparent about their AMU practices and the public improve their awareness for detecting marketers’ deceptive product labels that take advantage of public ignorance. Knowledge of these producers’ emotions would help educators target more successful behavioral change campaigns, improving stewardship in AMU practices among producers.

Factors Associated with Antimicrobial Stewardship Practices on California Dairies: One Year Post Senate Bill 27

BACKGROUND

The current study is aimed at identifying the factors associated with antimicrobial drug (AMD) use and stewardship practices on conventional California (CA) dairies a year after CA Senate Bill 27.

METHODS

Responses from 113 out of 1282 dairies mailed a questionnaire in 2019 were analyzed to estimate the associations between management practices and six outcomes including producer familiarity with medically important antimicrobial drugs (MIADs), restricted use of MIADs previously available over the counter (OTC), use of alternatives to AMD, changes in on-farm management practices, changes in AMD costs, and animal health status in dairies.

RESULTS

Producers who reported having a veterinarian-client-patient relationship (VCPR) and tracking AMD withdrawal intervals had greater odds of being familiar with the MIADs. Producers who began or increased the use of preventive alternatives to AMD in 2019 had higher odds (OR = 3.23, p = 0.04) of decreased use of MIADs previously available OTC compared to those who did not. Changes in management practices to prevent disease outbreak and the use of diagnostics to guide treatment were associated with producer-reported improved animal health. In addition, our study identified record keeping (associated with familiarity with MIADs), use of alternatives to AMD (associated with management changes to prevent diseases and decreased AMD costs), and use of diagnostics in treatment decisions (associated with reported better animal health) as factors associated with AMD stewardship.

CONCLUSIONS

Our survey findings can be incorporated in outreach education materials to promote antimicrobial stewardship practices in dairies.

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

Antimicrobial resistance (AMR) is a global health emergency affecting humans and animals, diminishing the effectiveness of medication used to treat illness. The agri-food sector has attracted increased attention for imprudent antimicrobial use (AMU) and its contribution to AMR. Thus, ascertaining farmers' and veterinarians' behaviours surrounding AMU is essential to address imprudent AMU and generate behaviour change within the agri-food sector. Therefore, the aim of this critical review is to investigate, assess and collate the current body of evidence to identify psychosocial factors including knowledge, understanding, perceptions, attitudes and behaviours surrounding AMU. Database searches were limited to articles utilizing qualitative and quantitative methodologies, available in English with no restriction on publication year. Of the 1156 articles identified, 103 were retained for this review. Findings on the psychosocial aspects were thematically analysed. Five key themes emerged from the data: (i) knowledge and awareness of antimicrobials; (ii) attitudes towards antimicrobials; (iii) influential relationships; (iv) resources; and (v) factors influencing AMU. Results indicated that to overcome barriers experienced by key stakeholders, a carefully considered, evidence-based approach, incorporating behaviour change theory, is required when designing intricate interventions/strategies, in order to elicit successful and sustained AMU behaviour change.

Impact of the veterinary feed directive on Ohio cattle operations

Widespread use of antibiotics in U.S. livestock operations has been identified as a potential contributor to the rising rates of antibiotic-resistant bacterial infections. In response, the U.S. Food and Drug Administration (FDA) issued new rules in January 2017. GFI (Guide for Industry) #213 banned use of antibiotics for growth promotion and required veterinarian permission, via a revised Veterinary Feed Directive (VFD), to deliver antibiotics through feed. Many stakeholders expressed pre-implementation concerns regarding the rules' potential adverse effects on production and profitability. Our study employed qualitative and quantitative methods to investigate how implementation of GFI #213/VFD impacted Ohio cattle operations. We interviewed over fifty cattle farmers and eight large animal veterinarians to document changes in farm antibiotic use, management practices, and profitability. We also examined published government data for possible effects on overall meat production at the state and national levels. We found that the great majority of Ohio farmers reported little difficulty in complying with the VFD with minimal adverse impacts. Farm responses to the feed directive varied with operation size, type (beef or dairy), and whether producers had previously used fed antibiotics. The most commonly reported changes, by both producers and veterinarians, were more veterinary-client interactions, more paperwork/record-keeping, and decreased use of fed antibiotics. All veterinarians, many beef operators, but no dairy operators reported perceiving the VFD as beneficial; however, dairy operations reported less difficulty with compliance due to established working relationships with veterinarians. We found no evidence that the rules impacted the trajectory of state or national livestock output. In conclusion, GFI #213 was reported as not burdensome enough to prevent compliance, but inconvenient enough to incentivize reduced use of fed antibiotics (when previously used) without significant adverse effects, consistent with its goal of promoting judicious use of medically important antibiotics in order to preserve their effectiveness.

New York State dairy veterinarians' perceptions of antibiotic use and resistance: A qualitative interview study

Antimicrobial resistance (AMR) limits the ability to prevent and treat infection, making AMR one of the foremost threats to human and animal health. Animal agriculture's large use of antibiotics in food animals is an important factor in AMR. As such, policies to reduce antibiotic use and combat AMR in animal agriculture in the United States (US) have been in place or are developed. One key to the success of these policies in the US is understanding how a major stakeholder - veterinarians treating dairy cattle - perceive the scale of antibiotic use, the threat of AMR and the utility of antibiotic use policies. We interviewed 9 dairy veterinarians in New York State and conducted an iterative thematic analysis of their responses, through which five themes were identified: 1. veterinarians' views of the frequency and reasons for antibiotic misuse, 2. their ideas on reducing antibiotic use, 3. perceptions of AMR within the dairy industry, 4. view of organic farming and how it relates to animal welfare, and 5. the impact of consumers' beliefs on the dairy industry. Participants viewed antibiotic overuse as largely due to farmers' concern for the welfare of their cattle and desire to treat ailments swiftly. Interviewees believed that it was possible to reduce antibiotic use through regulation, such as the Veterinary Feed Directive and improved herd management activities, such as better colostrum management, culture-based mastitis treatment, and improved housing conditions. They did not view the dairy industry as a significant contributor to AMR, particularly when compared to the human medical industry. Interviewees also offered their (unsolicited) opinion on organic dairy farming in the US and expressed frustration with the limited treatment options available in organic dairy farming and how this dynamic may potentially compromise animal welfare. Finally, they commented on the impact of consumers' beliefs on the dairy industry, expressing frustration with how misinformation about the dairy industry has led to consumer driven changes. As consumer beliefs have an impact on the dairy industry, this influence could be leveraged to further decrease antibiotic use. These findings can help guide future efforts in veterinarian-client communication and the development and implementation of effective policies in New York State. These results also highlight the need for more quantitative research on antibiotic use in the dairy industry, as without this data it will be difficult to ascertain the true impact of policy interventions.

Survey on Antimicrobial Drug Use Practices in California Preweaned Dairy Calves

The California (CA) dairy industry was surveyed in July 2017 to evaluate producers' knowledge and perceptions and antimicrobial drug (AMD) use in preweaned dairy calves following the implementation of the nationwide veterinary feed directive final rule (VFD) in January 2017 and prior to statewide implementation of CA Senate Bill (SB) 27 in January 2018. Together, these regulations require veterinary oversight for all uses of medically important antimicrobial drugs (MIADs) administered to livestock in CA. Survey questionnaire was mailed to 1,361 CA Grade A milk producing dairies and calf ranches across CA resulting in a 12% (169) response. Most respondents (83%) were aware of the VFD and SB 27 changes. Use of antibiotics was perceived as important (77%) in raising preweaned dairy calves and judicious use of antibiotics was ranked as the most important antimicrobial stewardship practice, amongst record keeping, observing withdrawal periods, having a valid Veterinarian-Client-Patient-Relationship (VCPR), and use of alternatives to antibiotics. Treating sick calves was the major indication for AMD use (90.5%); however, few producers reported use of antibiotics to control (12.7%) or prevent disease (11%). Neomycin sulfate, chlortetracycline, oxytetracycline and sulfamethazine were the most used AMD. The respondents reported a decreased use of AMD in milk (10%) and in solid feed (5%), and discontinuation of one or more AMDs used in milk (18.6%) or in solid feed (5%) post-VFD rule implementation in 2017. Most respondents reported keeping treatment records and the information recorded included date (82%), dose (44%) and route (15%) of AMD used. A few respondents reported they had initiated use of alternatives to AMDs, such as vitamins (32.6%), minerals (25.6%), herbal remedies (11.6%) and pathogen specific antibodies (7%), post-VFD. The limited changes noted in AMD use could be attributed to the short period between the implementation of the VFD and the time of the survey. Our study outcomes identified opportunities to improve AMD use practices, including record keeping and use of AMD alternatives, and provides a baseline for future evaluation of the impact of these regulatory changes, as well as guidance for the future recommendations on best practices to promote judicious AMD use.

Antibiotics Use in Food Animal Production: Escalation of Antimicrobial Resistance: Where Are We Now in Combating AMR?

The use of antibiotics has been very beneficial to human health, animal wellbeing, and food production, however, there are no alternatives to antimicrobials in treating infectious diseases. Their use can contribute to the development of antimicrobial resistance, but the world has realized the need to combat antimicrobial resistance in recent decades due to the continued escalation of the problem jeopardizing human and veterinary medicine and food and environmental safety. Understanding the AMR and judicious use of antimicrobials are critical, and one health approach involving several sectors and multiple disciplines is important to tackle the problem. National, regional, and global action plans have been instigated to tackle the escalation of AMR. Antimicrobials are frequently used in food animal production. Therefore, food animal producers are important participants to prevent overuse and misuse of antimicrobials. Recent regulations to address the challenges have not been perceived well in animal farming communities. More awareness regarding these action plans and understanding the impact of AMR are needed. A nationwide survey of perceptions of food animal producers regarding AMR mitigation approaches should be conducted to evaluate the effectiveness of the current policies regarding antibiotics use and AMR. These outcomes should be incorporated in future policies and awareness campaigns targeting food animal producers.

Antimicrobial Resistance of Major Bacterial Pathogens from Dairy Cows with High Somatic Cell Count and Clinical Mastitis

Simple Summary

Mastitis is the most prevalent disease of dairy cattle that causes significant economic losses. Different agents cause mastitis which leads to increased somatic cell count (SCC) and low milk quality. Treating mastitis with antimicrobials is essential to reduce SCC and improve milk quality. Excessive use or misuse of antimicrobials in dairy farms leads to the development of antimicrobial resistant bacteria. The objectives of this study were (1) to isolate and identify the causative agent of mastitis and (2) determine antimicrobial resistance profiles of bacterial isolates. A total of 174 quarter milk samples from 151 cows with high SCC and clinical mastitis from 34 dairy farms in Tennessee, Kentucky, and Mississippi were collected. Bacterial causative agents were determined by bacteriological and biochemical tests. Antimicrobial resistance of bacterial isolates against 10 commonly used antimicrobials was tested. A total of 193 bacteria consisting of six bacterial species, which include Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae were isolated. Staphylococcus aureus was the predominant isolate. The proportion of resistant isolates was relatively higher in Gram-negatives than Gram-positives. Continuous antimicrobial resistance testing and identification of reservoirs of resistance traits in dairy farms are essential to implement proper mitigation measures.

Abstract

Mastitis is the most prevalent and economically important disease caused by different etiological agents, which leads to increased somatic cell count (SCC) and low milk quality. Treating mastitis cases with antimicrobials is essential to reduce SCC and improve milk quality. Non-prudent use of antimicrobials in dairy farms increased the development of antimicrobial resistant bacteria. This study’s objectives were (1) to isolate and identify etiological agents of mastitis and (2) to determine antimicrobial resistance profiles of bacterial isolates. A total of 174 quarter milk samples from 151 cows with high SCC and clinical mastitis from 34 dairy farms in Tennessee, Kentucky, and Mississippi were collected. Bacterial causative agents were determined by bacteriological and biochemical tests. The antimicrobial resistance of bacterial isolates against 10 commonly used antimicrobials was tested. A total of 193 bacteria consisting of six bacterial species, which include Staphylococcus aureus, Streptococcus uberis, Streptococcus dysgalactiae, Escherichia coli, Klebsiella oxytoca and Klebsiella pneumoniae were isolated. Staphylococcus aureus was the predominant isolate followed by Strep. spp., E. coli, and Klebsiella spp. Results of this study showed that Gram-negatives (E. coli and Klebsiella spp.) were more resistant than Gram-positives (Staph. aureus and Streptococcus spp.). Continuous antimicrobial resistance testing and identification of reservoirs of resistance traits in dairy farms are essential to implement proper mitigation measures.

Addressing Individual Values to Impact Prudent Antimicrobial Prescribing in Animal Agriculture

Antimicrobial resistance is a growing public health threat driven by antimicrobial use—both judicious and injudicious—in people and animals. In animal agriculture, antimicrobials are used to treat, control, and prevent disease in herds of animals. While such use generally occurs under the broad supervision of a veterinarian, individual animals are often treated by farm owners or managers. The decision to administer antimicrobials is therefore influenced not only by the clinical situation but also by the motivations and priorities of different individual actors. Many studies have examined the drivers of external forces such as costs, workload and time constraints, or social pressures on antimicrobial use by veterinarians and producers, but none have explored the role of individually held values in influencing decision-making related to antimicrobial use. Values are deeply held normative orientations that guide the formation of attitudes and behaviors across multiple contexts. Values have been shown to be strongly tied to perceptions of and attitudes toward polarizing topics such as climate change, and preliminary evidence suggests that values are also associated with attitudes to antimicrobial resistance and stewardship. In this article, we draw on lessons learned in other fields (human health care, climate change science) to explore how values could be tied to the extrinsic and intrinsic factors that drive antimicrobial use and prescribing in animal agriculture. We also provide suggestions for ways to build a bridge between the veterinary and social sciences and incorporate values into future research aimed at promoting antimicrobial stewardship in animal agriculture.

New York State dairy farmers' perceptions of antibiotic use and resistance: A qualitative interview study

Antibiotic resistance is a global problem affecting both human and animal health. Ensuring the strategic and effective use of antibiotics is paramount to combatting the emergence and spread of resistance. This study explored New York State (NYS) dairy farmers' perceptions regarding antibiotic use in dairy farming and antibiotic resistance. Dairy farmers' perceptions were assessed through semi-structured, in-person interviews. Twenty interviews with farm owners and/or managers of 15 conventional and five USDA certified organic dairy farms with 40 to 2,300 lactating cows were conducted. Thematic analysis was used to assess, compare and contrast transcripts for farmers' characterization of their beliefs, values, and concerns. Conventional dairy farmers had a low level of concern about the possible impacts of on-farm antibiotic resistance on human health and believed their antibiotic use was already judicious. Generally, they believed their cattle's health would suffer if antibiotic use were further curtailed. Conventional farmers expressed frustration over the possibility of more stringent governmental, milk cooperative, buyer, or marketer requirements for antibiotic use and associated animal welfare in the future. They attributed expanding regulations in part to misinformed consumer preferences, that farmers felt were influenced by the marketing of organic dairy products. Organic dairy farmers were generally more concerned about issues related to antibiotic resistance than conventional farmers. Both conventional and organic farmers placed emphasis on disease prevention through herd health management rather than treatment. In conclusion, the conventional NYS dairy farmers in this study were skeptical of the need for and benefits of reduced antibiotic use on their dairy farms. Interventions for farmers, delivered by a trusted source such as a veterinarian, that provide training about proper antibiotic use practices and information of possible financial benefits of refining antibiotic use may hold promise.