Study on knowledge, attitudes and behavioral practices of antimicrobial usage and resistance in animals and humans in Bahir Dar City, Northwest Ethiopia.

Antimicrobial resistance has emerged as one of the foremost global public health challenges. While not a new issue, AMR has gained increasing attention due to the rise of multi-resistant pathogenic organisms, leading to higher mortality rates and significant economic burdens. To assess the knowledge, attitudes, and practices of the Bahir Dar City community regarding human and animal antimicrobial use and AMR, a community-based cross-sectional study was conducted from February to June 2023. The study area was selected purposively, and a simple random sampling approach was used to select kebeles, households, and individual participants. A total of 400 participants were enrolled in the study, with 63.25% being male and 31.25% having graduated from secondary school. Additionally, 61.5% of respondents were married, and the majority (46.5%) owned two species of animals. The findings revealed that 48.5% of the participants had moderate knowledge, 57.5% had positive attitudes, and 52.75% demonstrated good practices regarding antimicrobial resistance and usage. Chi-square analysis revealed statistically significant associations (p < 0.05) between respondents' knowledge level and their educational level, marital status, and position in the house. Attitude level were significantly associated (p < 0.05) with educational level, marital status, occupation, house ownership, and position in the house. Practice level also showed significant association (p < 0.05) with position in the house and occupation. Furthermore, there were significant associations among knowledge, attitude, and practice: knowledge was significantly associated with attitude (χ2 = 209.91, p ≤ 0.001), knowledge with practice (χ2 = 160.43, p ≤ 0.001), and attitude with practice (χ2 = 136.95, p ≤ 0.001). In conclusion, the study found a moderate level of knowledge, positive attitude, and good practice regarding antimicrobial usage and resistance among participants. It is recommended to promote responsible antimicrobial use across all sectors and encourage interdisciplinary collaboration.

Conventional and unsupervised artificial intelligence analyses identified risk factors for antimicrobial resistance on dairy farms in the province of Québec, Canada.

Antimicrobial resistance (AMR) is one of the greatest threats to global health worldwide and is threatening not only humans, but also animal production systems, including dairy farms. The objective of this paper was to describe risks factors associated with AMR on dairy farms in Québec, Canada. This observational cross-sectional study included 101 commercial dairy farms and took place between the springs of 2017 and 2018 for a one-year period. We explored risk factors such as farm practices and producer's knowledge (measured using a questionnaire), antimicrobial use (quantified using veterinary invoices), and the presence of Salmonella Dublin (tested by serology). We evaluated AMR with fecal Escherichia coli retrieved from pre-weaned calves and lactating cows using the following outcomes: the presence of extended-spectrum-ß-lactamase/AmpC resistance and the number of resistances to antimicrobial classes. We used logistic regression models to evaluate the association between each risk factor and the 2 outcomes for the 2 types of samples (pre-weaned calves and lactating cows). Furthermore, we explored the relationships between these risk factors utilizing data dimensionality reduction and hierarchical clustering. Outputs of these analyses were used as regressors for AMR in regression models. While the results for univariate analyses were ambiguous, the unsupervised analysis naturally categorized the sample of farms according to their health/treatment status (dimension 1, explaining 12.9% of the variance) and herd size (dimension 2, explaining 7.8%). Three clusters of farms were identified (cluster 1: mainly healthy herds and low ceftiofur users, cluster 2: relatively high ceftiofur users, cluster 3: farms with a higher incidence of diseases and higher antimicrobial treatment rates). Dimension 1 and cluster membership were statistically associated with the presence of extended-spectrum-ß-lactamase/AmpC resistance in lactating cows and in pre-weaned calves. Dimension 1 was also statistically associated with the number of resistances in lactating cows and in pre-weaned calves. This study highlights the complexity of analyzing risk factors associated with AMR. Our results suggest that the herd health status and the AMU-related practices used are associated with AMR in dairy farms. However, prospective studies are needed to confirm a causal relation.

Effect of a dairy farmworker stewardship training program on antimicrobial drug usage in dairy cows.

Antimicrobial use (AMU) is critical to preserving animal health and welfare. However, the development of antimicrobial resistance (AMR) represents a public health threat. Although most antimicrobials used on the farm require a veterinarian prescription, farmworkers make daily on-farm treatment decisions. Therefore, farmworker training is vital to promote responsible AMU. This research project aimed to evaluate the effect of farmworker antimicrobial stewardship (AMS) training on the quantity of AMU on dairy farms in Ohio and California. We hypothesized that farms receiving AMS training would have reduced AMU in dairy cattle compared with farms where training wasn't administered. We designed a quasiexperimental study with 18 conventional dairy farms enrolled in Ohio and California. Twelve farms received AMS training, and 6 farms did not. The AMS program included a 12-wk training focused on accurate identification of cows requiring antimicrobial treatment. We quantified AMU by collecting used drug containers, manually counted by researchers during farm visits. Treatment incidence (TI) was calculated using animal daily doses (ADD), and Poisson regression models were used to analyze the TI data. Disease incidence rate (DIR) in lactating cows was 2.2, 1.5, 1.0, 0.4, 0.3, 0.2, and 0.03/1,000 cow-days for mastitis, lameness, metritis, pneumonia, retained placenta, diarrheas, and other diseases (e.g., conjunctivitis, injuries), respectively. The highest TI by antimicrobial class (provided in ADD/1,000 cow-days) was cephalosporin (5.9), penicillin (5.2), tetracyclines (0.4), lincosamides (0.2), and sulfonamides (0.1). Among the trained farms using a within-treatment group analysis, no significant differences were observed in TI pre-intervention (10.9 ADD/1,000 cow-days) compared with TI postintervention (10.3 ADD/1,000 cow-days). Treatment incidence from the training group was 10.8 ADD/1,000 cow-days and although numerically lower, it was not significantly different compared with TI in the control groups at 13.9 ADD/1,000 cow-days (rate ratio = 0.77, CI = 0.25-2.38). Future research on AMS should incorporate farmworker training with social science approaches to overcome barriers and promote on-farm responsible use.

Antimicrobial Resistance Profiles of Campylobacter spp. Recovered from Chicken Farms in Two Districts of Bangladesh.

The rapid emergence of antimicrobial resistance (AMR) in Campylobacter has reinforced its status as a foodborne pathogen of significant public health concern. Resistant Campylobacter is typically transferred to humans via the consumption of contaminated animal products, particularly poultry. The genes associated with antimicrobial resistance in Campylobacter spp. are poorly understood. To address this knowledge gap, we conducted a prevalence survey of AMR Campylobacter across 84 chicken farms in two districts of Bangladesh. Pooled cloacal swabs were collected from chickens and underwent bacteriological testing for Campylobacter spp. with PCR confirmation. Antimicrobial susceptibility was tested against 14 antibiotics by disk diffusion method, and 12 resistance genes were screened in Campylobacter-positive isolates using multiplex PCR. A total of 34 (40.5%) farms were Campylobacter-positive of which 73.5% of isolates were resistant to at least 10 antibiotics. The antimicrobial susceptibility results indicate a high level of resistance against streptomycin (97.1%), clindamycin (97.1%), ampicillin (94.1%), tetracycline (94.1%), erythromycin (91.2%), ciprofloxacin (88.2%), nalidixic acid (85.3%), and imipenem (82.4%), and comparatively a low frequency of resistance to chloramphenicol (47.1%), ceftazidime (44.1%), and colistin (35.3%). Multidrug-resistant (MDR) and extensively drug-resistant Campylobacter were identified in 97.1%, and 50% of isolates, respectively. Ten resistance genes were identified including blaTEM (in 97.1% of isolates), strA-strB (85.9%), tetA (70.6%), tetB (32.4%), qnrS (23.5%), blaCTX-M-1 (20.6%), qnrB (20.6%), blaSHV (8.8%), aadB (5.9%), and qnrA (2.9%). Our findings demonstrate that resistance to ampicillin, tetracycline, and ceftazidime in Campylobacter isolates was significantly (p ≤ 0.05) associated with the presence of blaTEM, tetA, and blaSHV genes, respectively. The high rates of AMR in Campylobacter isolates from our study are not surprising given the liberal use of antimicrobials and incomplete biosecurity provisions on farms. Of particular concern are resistance rates to those classes of antibiotics that should be reserved for human use (azithromycin, ciprofloxacin, and colistin). AMR was more prevalent in chicken farms that used multiple antibiotics, engaged in prophylactic treatment of the birds, and improperly disposed of antibiotic packages. The high prevalence of MDR in chicken-derived Campylobacter isolates from the different regions of our study reinforces the need for more prudent use of antimicrobial compounds in Bangladeshi chicken farms.

Collecting Multi-country Retrospective Antimicrobial Consumption and Use Data: Challenges and Experience.

Excessive or inappropriate antimicrobial use contributes to antimicrobial resistance, emphasizing the need to monitor and document the types and quantities of antibiotics used. Thus, data on antimicrobial consumption (AMC) and antimicrobial usage (AMU) are key in informing and promoting judicious use. Our study, conducted during 2019-2023, as part of the CAPTURA project, aimed to understand the state of data availability and quality for AMC and AMU monitoring in Asia. In this article, we describe the challenges and opportunities faced and provide examples of AMU and AMC analysis. World Health Organization (WHO) and country-tailored methodologies and tools were applied to collect retrospective data from 2016 to 2019 in Bangladesh, Bhutan, Laos, Nepal, Pakistan, Papua New Guinea, Sri Lanka, and Timor-Leste. The primary indicator for national AMC was total level of consumption, expressed as total defined daily doses (DDD) per 1000 inhabitants per day for the year or period of data collected. For facility AMC and AMU, the primary indicator was total DDD per admissions per day for the year or period of data collected. Although many countries faced infrastructural challenges in data collection and storage, we managed to collect and analyze AMC data from 6 countries and AMU data from 5. The primary indicators, and additional findings, were visualized to facilitate dissemination and promote the development of action plans. Looking ahead, it is crucial that future initiatives empower each country to establish surveillance infrastructures tailored to their unique contexts, ensuring sustainable progress in the fight against antimicrobial resistance.

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.

Single-center survey of prescription trends and appropriate use plans for macrolide antimicrobials.

INTRODUCTION: Macrolides (MCs) are broad-spectrum antimicrobials with activity against many microorganisms. They are widely used, and the development of MC-resistant bacteria is a serious problem in Japan. It is therefore necessary to clarify the purpose and duration of administration, with the aim of promoting appropriate use. METHODS: Patients of all ages, for whom oral MCs were prescribed between 2016 and 2020 were included. They were divided into four groups based on the number of days per prescription. In the long-term treatment group, patients treated with MCs for ≥1000 days were specifically investigated for the purpose of treatment. RESULTS: Macrolide prescriptions increased from 2019 to 2020. Most patients received ≥28 days of treatment based on one prescription. During the study period, 1212 patients (28.6%) received a total of ≥50 days and 152 patients (3.6%) received a total of ≥1000 days of treatment. Approximately a third of long-term administrations were for nontuberculous mycobacterial infections (NTMs), and 18.3% of patients with NTMs were treated with MCs alone. In addition, many MCs were administered for their anti-inflammatory effects on neutrophils. CONCLUSIONS: Owing to their pleiotropic effects, MCs may also be administered for the treatment of noninfectious diseases. In general, the long-term administration of antimicrobials contradicts the strategy for the suppression of resistant bacteria. It is thus important to understand the actual clinical utility of MCs and the purpose and duration of administration. In addition, strategies for the appropriate use of MCs are required for each medical institution.

Economic evaluation of antimicrobial usage surveillance in livestock.

There is increased pressure by governments and industry to develop national surveillance programmes to evaluate antimicrobial usage (AMU) in animals. This article presents a methodological approach to cost-effectiveness analysis of such programmes. Seven objectives are proposed for AMU surveillance in animals: quantifying use, finding trends, detecting hotspots, identifying risk factors, encouraging research, evaluating the impact of policies and diseases, and demonstrating compliance with regulations. Achieving these objectives would assist in making decisions about potential interventions, help to generate trust, incentivise the reduction of AMU and decrease the risk of antimicrobial resistance. The cost-effectiveness of each objective can be found by dividing the cost of the programme by the performance indicators of the surveillance required to meet the objective concerned. The precision and accuracy of surveillance outputs are suggested here as useful performance indicators. Precision depends on the level of surveillance coverage (SC) and surveillance representativeness (SR). Accuracy is influenced by the quality of farm records and SR. The authors argue that there is an increase in marginal cost for each unit increase of SC, SR and data quality. This is caused by the increasing difficulty of recruiting farmers due to potential barriers such as staff capacity, capital availability, computing literacy and availability, and geographical differences, among other factors. A simulation model was conducted to test the approach, using the quantification of AMU as the primary objective, and to provide evidence of the application of the law of diminishing returns. Cost-effectiveness analysis can be used to support decisions on the level of coverage, representativeness and data quality required in such AMU programmes.

Les gouvernements tout comme le secteur de l'élevage exercent une pression croissante pour que des programmes nationaux de surveillance soient élaborés afin d'évaluer l'utilisation d'agents antimicrobiens (UAM) chez les animaux. Cet article présente une approche méthodologique permettant de réaliser l'analyse coût-efficacité de ces programmes. Sept objectifs sont proposés pour la surveillance de l'UAM chez les animaux : quantifier cette utilisation, relever les tendances, détecter les situations d'utilisation intensive, déceler les facteurs de risque, encourager la recherche, évaluer l'impact des politiques et des maladies et démontrer la conformité avec les réglementations. La réalisation de ces objectifs de surveillance permettra de prendre des décisions éclairées sur les interventions à mener, contribuera à mettre en place un climat de confiance, encouragera à réduire l'UAM et atténuera le risque d'apparition d'antibiorésistances. Le ratio coût-efficacité de chaque objectif peut être déterminé en divisant le coût du programme par les indicateurs de performance de la surveillance requise pour chacun des objectifs examinés. Les auteurs considèrent que la précision et l'exactitude des résultats de la surveillance sont des indicateurs de performance utiles à cet effet. La précision dépend du niveau de couverture de la surveillance (CS) et de sa représentativité (RS). L'exactitude est fonction de la qualité des registres d'élevage et de la RS. D'après les auteurs, chaque accroissement unitaire de la CS, de la RS et de la qualité des données donne lieu à une augmentation du coût marginal. Celle-ci s'explique par la difficulté croissante de recruter des éleveurs pour cette activité, en raison d'obstacles tels que le manque d'effectifs, la disponibilité de capitaux, le manque de compétences et d'équipements informatiques et les différences géographiques, entre autres facteurs potentiels. Un modèle de simulation a été mis en oeuvre pour tester cette approche à partir de l'objectif principal (la quantification de l'UAM), et pour apporter des éléments démontrant l'application de la loi des rendements décroissants dans ce domaine. L'analyse coût-efficacité peut être utilisée pour étayer les décisions concernant la couverture, la représentativité et la qualité des données requises pour les programmes de surveillance de l'UAM.

Los gobiernos y la industria vienen presionando cada vez más para la implantación de programas nacionales de vigilancia destinados a evaluar el uso de agentes antimicrobianos (UAM) en los animales. Los autores presentan una solución metodológica para analizar la relación costo-eficacia de tales programas. En primer lugar proponen un conjunto de siete objetivos que deben cumplirse al vigilar el UAM en los animales: cuantificar el uso, detectar tendencias, localizar áreas de "gran intensidad" de uso, determinar los factores de riesgo, alentar la investigación, evaluar la repercusión de las políticas y las enfermedades y comprobar la observancia de los reglamentos. El logro de estos objetivos ayudaría a decidir sobre posibles intervenciones y a generar confianza, supondría un incentivo para reducir el UAM y atenuaría el riesgo de que surgieran resistencias a estos productos. Para cada objetivo es posible determinar la relación costo-eficacia dividiendo el costo del programa por los indicadores de desempeño de la vigilancia requerida para cumplir el objetivo en cuestión. Los autores proponen utilizar la precisión y exactitud de los resultados de la vigilancia como útiles indicadores de desempeño. La precisión depende del nivel de cobertura y de representatividad de la vigilancia. En la exactitud, por su parte, influyen la calidad de los archivos de las explotaciones pecuarias y la representatividad de la vigilancia. Los autores postulan que cada aumento unitario de la cobertura y la representatividad de la vigilancia y de la calidad de los datos se acompaña de un aumento correspondiente del costo marginal. Ello se explica por la creciente dificultad que presenta la participación de ganaderos en el proceso, debida a su vez a posibles barreras en aspectos como la dotación de personal, el capital disponible, los conocimientos en informática y el acceso a ordenadores o las diferencias geográficas, entre otros factores. Para ensayar el método y probar que se aplica el principio de los rendimientos decrecientes, los autores emplearon un modelo de simulación, utilizando como principal objetivo la cuantificación del UAM. El análisis de la relación costo-eficacia puede ser utilizado como herramienta auxiliar para tomar decisiones sobre el nivel de cobertura, representatividad y calidad de los datos que se necesita en este tipo de programas de vigilancia del UAM.

Diagnostic Performance of Metagenomic Next-Generation Sequencing in Pediatric Patients: A Retrospective Study in a Large Children's Medical Center.

BACKGROUND: Metagenomic next-generation sequencing (mNGS) has the potential to become a complementary, if not essential, test in some clinical settings. However, the clinical application of mNGS in a large population of children with various types of infectious diseases (IDs) has not been previously evaluated. METHODS: From April 2019 to April 2021, 640 samples were collected at a single pediatric hospital and classified as ID [479 (74.8%)], non-ID [NID; 156 (24.4%)], and unknown cases [5 (0.8%)], according to the final clinical diagnosis. We compared the diagnostic performance in pathogen detection between mNGS and standard reference tests. RESULTS: According to final clinical diagnosis, the sensitivity and specificity of mNGS were 75.0% (95% CI: 70.8%-79.2%) and 59.0% (95% CI: 51.3%-66.7%), respectively. For distinguishing ID from NID, the sensitivity of mNGS was approximately 45.0% higher than that of standard tests (75.0% vs 30.0%; P < 0.001). For fungal detection, mNGS showed positive results in 93.0% of cases, compared to 43.7% for standard tests (P < 0.001). Diagnostic information was increased in respiratory system samples through the addition of meta-transcriptomic sequencing. Further analysis also showed that the read counts in sequencing data were highly correlated with clinical diagnosis, regardless of whether infection was by single or multiple pathogens (Kendall's tau b = 0.484, P < 0.001). CONCLUSIONS: For pediatric patients in critical condition with suspected infection, mNGS tests can provide valuable diagnostic information to resolve negative or inconclusive routine test results, differentiate ID from NID cases, and facilitate accurate and effective clinical therapeutic decision-making.

Modelling the effects of antimicrobial metaphylaxis and pen size on bovine respiratory disease in high and low risk fattening cattle.

Bovine respiratory disease (BRD) dramatically affects young calves, especially in fattening facilities, and is difficult to understand, anticipate and control due to the multiplicity of factors involved in the onset and impact of this disease. In this study we aimed to compare the impact of farming practices on BRD severity and on antimicrobial usage. We designed a stochastic individual-based mechanistic BRD model which incorporates not only the infectious process, but also clinical signs, detection methods and treatment protocols. We investigated twelve contrasted scenarios which reflect farming practices in various fattening systems, based on pen sizes, risk level, and individual treatment vs. collective treatment (metaphylaxis) before or during fattening. We calibrated model parameters from existing observation data or literature and compared scenario outputs regarding disease dynamics, severity and mortality. The comparison of the trade-off between cumulative BRD duration and number of antimicrobial doses highlighted the added value of risk reduction at pen formation even in small pens, and acknowledges the interest of collective treatments for high-risk pens, with a better efficacy of treatments triggered during fattening based on the number of detected cases.

A multivariable analysis of the contribution of socioeconomic and environmental factors to blood culture Escherichia Coli resistant to fluoroquinolones in high- and middle-income countries.

BACKGROUND: Antimicrobial resistance (AMR) is a public health concern. We wanted to determine if various environmental and socioeconomic variables as well as markers of antimicrobial use impacted on the level of AMR in countries of different income levels. METHODS: We performed cross-national univariate and multivariable analyses using the national proportion of quinolone-resistant Escherichia coli (QREC) in blood culture as the dependent variable. Access to safe water and sanitation, other socioeconomic variables, and human and animal antimicrobial consumption were analysed. RESULTS: In middle-income countries, unsafely managed sanitation, corruption and healthcare access and quality were significantly associated with the national proportion of blood culture QREC (%) in univariate analyses, whereas no variables remained significant in the multivariable models. For the multivariable high-income country model, corruption and healthcare access and quality were significantly associated with blood culture QREC (%) levels. For the model including all countries, human fluoroquinolone use, corruption level, livestock and crop production index were significantly associated with blood culture QREC (%) levels in the univariate analyses. CONCLUSION: Corruption is a strong predictor of AMR, likely reflecting a multitude of socioeconomic factors. Sanitation quality contributed to increased blood culture QREC (%) levels in middle-income countries, although was not an independent factor, highlighting the need to also focus on infrastructure such as sanitation services in the context of AMR.

Association between antimicrobial usage and resistance in Salmonella from poultry farms in Nigeria.

BACKGROUND: Antimicrobial resistance (AMR) is a global health threat affecting treatment outcome in animals and humans. A pre-requisite for development of AMR reduction strategies is knowledge of antimicrobial use patterns, and how these affect resistance development. The aim of this study was to determine antimicrobial usage (AMU) and whether such usage was associated with AMR in Salmonella from poultry farms in Northwest Nigeria. RESULTS: Fifteen (37%) of antimicrobial products observed contained compounds that are of highest priority and critically important for human medicine. Broilers chicken consumed higher (28 ± 14 mg/kg active ingredients) amounts of antimicrobials compared to layers (13 ± 8 mg/kg) per week (p = 0.0009). Surprisingly, chickens raised under backyard system consumed higher amounts of antimicrobials (34 ± 7 mg/kg) than poultry in other systems (p = 0.02). High levels of resistance to tetracycline (58%), sulphonamides (65%), ciprofloxacin (46%) and gentamicin (42%) correlated with high farm level usage of these antimicrobials, and there was a strong correlation (r = 0.9) between farm usage and resistance of isolates to the same antimicrobials (p = 0.03). CONCLUSION: High AMU, including use of highest priority critically important antimicrobials was observed at poultry farms in Northwest Nigeria. AMU correlated with high levels of resistance. Communication of prudent use of antimicrobials to farmers and regulation to obtain reduction in AMU should be a priority.

The effectiveness of prescription support and treatment reporting system on the appropriate usage of oral third-generation cephalosporins.

INTRODUCTION: Preauthorization and prospective audit and feedback system are reported to be effective for the achievement of appropriate use of intravenous antimicrobials, but few reports on oral antimicrobials are available, especially for adults. METHODS: The prescription of oral third-generation cephalosporins (oral 3rd Ceph) for inpatients and outpatients from 2013 to 2018 was investigated. The study period was divided into three phases. First, prescription support to suggest discontinuation of antimicrobials for unnecessary prescriptions, and alternative antimicrobials for inappropriate prescriptions were provided. Next, we continued prescription monitoring, and observed the trends of antimicrobial prescription without support. Finally, we have introduced prescription reporting system to promote the appropriate use of oral 3rd Ceph. In each phase, we evaluated days of therapy per 1000 patient-days and prescriptions per 1000 visits as an index of effectiveness of our interventions. RESULTS: The total annual amount of oral 3rd Ceph usage decreased significantly over time between phases, respectively. During the same period, the incidence rate of methicillin-resistant Staphylococcus aureus (MRSA), extended spectrum ß-lactamase (ESBL)-producing bacteria, and AmpC ß-lactamase (AmpC)-producing bacteria was not changed significantly, indicating that oral 3rd Ceph usage was reduced without a concomitant increase of the drug-resistant bacteria. Simultaneously, the annual usage of other broad-spectrum antimicrobial agents such as oral fluoroquinolones and oral macrolides also decreased, which indicated these antimicrobials were not prescribed as an alternative for oral 3rd Ceph. CONCLUSIONS: The combination of prescription support activity and treatment reporting system for oral antimicrobial agents is an effective method for promoting appropriate oral antimicrobial use.

Quantification of antimicrobial usage in adult cows and preweaned calves on 40 large Wisconsin dairy farms using dose-based and mass-based metrics.

Use of antimicrobials in animal agriculture is under increasing scrutiny, but the quantity of antimicrobials used on large US dairy farms has not been evaluated using data from large farms and different metrics. This study investigated total antimicrobial usage (AMU) in adult dairy cows and preweaned calves (PWC) and contrasted 2 metrics used for measurement of AMU. Wisconsin dairy farms were eligible if they had >250 lactating cows, maintained computerized animal health records, and were willing to allow researchers access to treatment records. Animal health data for a 1-yr period was retrospectively collected from computerized records, and a farm visit was performed to verify case definitions and recording accuracy. Both dose-based (animal daily doses; ADD) and mass-based (total mg of antimicrobials per kg of body weight; BW) metrics were calculated at the herd, cow, and PWC levels. Descriptive statistics for AMU were examined for both age groups. Mean AMU was compared among active ingredients and route of usage using ANOVA models that included farm as a random variable. At enrollment, farms (n = 40) contained approximately 52,639 cows (mean: 1,316 ± 169; 95% CI: 975, 1657) and 6,281 PWC (mean: 180 ± 33; 95% CI: 112, 247). When estimated using ADD, total herd AMU was 17.2 ADD per 1,000 animal-days (95% CI: 14.9, 19.5), with 83% of total herd-level AMU in adult cows. When estimated using the mass-based metric, total herd AMU was 13.6 mg of antimicrobial per kilogram of animal BW (95% CI: 10.3, 17.0), with 86% of total AMU used in adult cows. For cows, 78% of total ADD (15.8 ADD per 1,000 cow-d) was administered as intramammary (IMM) preparations. In contrast, when AMU was estimated using a mass-based metric, IMM preparations represented only 24% of total AMU (12.1 mg of antimicrobial/kg of cow BW). For cows, ceftiofur was the primary antimicrobial used and accounted for 53% of total ADD, with 80% attributed to IMM and 20% attributed to injectable treatments. When estimated using a mass-based metric, ampicillin was the predominant antimicrobial used in cows and accounted for 33% of total antimicrobial mass per kilogram of BW. When AMU was estimated for PWC using ADD, injectable antimicrobials represented 79% of total usage (28.3 ADD per 1,000 PWC-d). In contrast, when AMU was estimated for PWC using a mass-based metric, injectable products represented 42% of total AMU, even though more farms administered antimicrobials using this route. When AMU in PWC was summarized using ADD, penicillin represented 32% of AMU, and there were no significant differences in ADD among ampicillin, oxytetracycline or enrofloxacin. When a mass-based metric was used to estimate AMU in PWC, oral products (sulfadimethoxine and trimethoprim-sulfa) represented more than half of the total AMU given to this group. Overall, these results showed that choice of metric and inclusion of different age groups can substantially influence interpretation of AMU on dairy farms.

Monitoring udder health on routinely collected census data: Evaluating the short- to mid-term consequences of implementing selective dry cow treatment.

In 2013, the preventive use of antimicrobials in Dutch livestock was prohibited, including a ban on the blanket application of antimicrobial dry cow treatment (BDCT). Since then, selective dry cow treatment (SDCT) has become the standard approach. In this study, we aimed to determine the effect of the ban on BDCT and the extent of the subsequent adoption of SDCT on antimicrobial usage (AMU) and udder health on Dutch dairy farms. In the Dutch cattle health surveillance system, AMU for dry cow treatment (AMUDCT), AMU for intramammary treatment at any point in time (AMUIMM), and udder health indicators are routinely and continuously monitored. This provided the opportunity to study associations among SDCT, udder health, and AMU on census data of approximately 17,000 dairy herds, with about 1.67 million cows in total (>2 yr old) at one moment in time in the period from 2013 until 2017. Six udder health parameters were evaluated using multivariable population-averaged generalized estimating equation models. The year in which the ban on BDCT was introduced (2013) was compared with the period thereafter (2014-2017). Additionally, AMUIMM and AMUDCT were included as independent variables to evaluate whether the extent to which SDCT was implemented on the herd level was associated with udder health. Demographic parameters were included as potential confounders. Since the ban on BDCT, overall declines of 63% in AMUDCT and 15% in AMUIMM were observed. The raw data show an improvement in 5 out of 6 evaluated udder health parameters between 2013 and 2017. Nevertheless, the multivariable model results showed that the period since the ban on BDCT was associated with a small but significant increase in the percentage of cows with high somatic cell count (HSCC) and new HSCC (+0.41% and +0.06%, respectively). Additionally, the probability of belonging to the group of herds with more than 25% of primiparous cows having HSCC during the start of lactation increased slightly, associated with the period after which BDCT was banned (odds ratio = 1.08). The probability of belonging to the group of herds with more than 25% cows having a persistent HSCC during the dry period was not affected and bulk milk somatic cell count showed a slight but significant reduction. The only udder health parameter that notably worsened during the study period was the probability of belonging to the group of herds with more than 25% of multiparous cows with a new HSCC after the dry period, during the start of lactation (odds ratio = 1.23). In herds where the farmer decided not to apply any dry cow therapy (≈20% of all herds), all udder health parameters were poorer compared with herds in which dry cow therapy was applied to some extent. The ban on BDCT and implementation of SDCT in the Netherlands was associated with a considerable reduction in AMU without a major impairment in udder health at the national level. Although negative effects of changed dry cow management were observed in some herds, we conclude that SDCT can be introduced without substantial negative effects on udder health.

Antimicrobial use and farmers' attitude toward mastitis treatment on dairy farms with automatic or conventional milking systems.

Mastitis is one of the major causes for antimicrobial use on dairy cattle farms. On farms with an automatic milking system (AMS), diagnostics differ from those with a conventional milking system (CMS), with potentially a different attitude toward mastitis treatment. This may result in differences in antimicrobial usage (AMU) between these 2 types of farms. The aims of this study were (1) to compare AMU between AMS and CMS farms, (2) to identify variables associated with AMU in both types of herds, and (3) to describe the distribution of mastitis-causing pathogens and their antimicrobial resistance patterns. Data on AMU was collected for 42 AMS and 254 CMS farms in the Netherlands and was expressed as animal-defined daily dose (ADDD). The ADDD variables were total usage (ADDDTOTAL), intramammary usage during lactation (ADDDIMM), usage for dry cow therapy (ADDDDCT), and usage by injection (ADDDINJ). Eighteen AMS farms and 24 CMS farms participated in a survey on factors potentially related to AMU. These farmers collected 5 quarter milk samples from quarters with clinical mastitis or high somatic cell count, which were subjected to bacteriological culture and antimicrobial susceptibility testing. In addition, routinely collected udder health data of these farms were used in the analysis. Nonlinear principal component analysis (NLPCA) was used to explore associations between AMU, udder health, and questionnaire variables. The ADDDTOTAL and ADDDDCT were comparable between AMS and CMS farms, whereas ADDDIMM tended to be lower and ADDDINJ higher on AMS farms than on CMS farms. The NLPCA yielded 3 principal components (PC) that explained 48% of the variation in all these variables. The AMS farms were not distinguished from CMS farms in the principal component space. The 3 PC represented different aspects of udder health, ADDDTOTAL, and treatment strategy. Differences in treatment strategy were unrelated to total antimicrobial usage or overall udder health. The distribution of mastitis-causing pathogens and their antimicrobial resistance were comparable between AMS and CMS farms. In conclusion, our study shows that AMU on AMS farms was similar to that of CMS farms, but AMS farmers tend to apply more injectable and fewer intramammary treatments during lactation than CMS farmers. Across both farm types, farmers' attitudes toward udder health in general and toward mastitis treatment are associated with AMU.

Single Layer Centrifugation with 20% or 30% Porcicoll separates the majority of spermatozoa from a sample without adversely affecting sperm quality.

Centrifugation of boar semen through one layer of 40% colloid (Porcicoll) was previously shown to separate spermatozoa from bacteria without having a detrimental effect on sperm quality. However, some spermatozoa were lost. The purpose of the present study was to determine whether 20% or 30% Porcicoll could be used to recover most of the spermatozoa without impacting on sperm quality. Insemination doses (n = 10) from a commercial boar station were sent to the laboratory at the Swedish University of Agricultural Sciences and processed by Single Layer Centrifugation with 20% and 30% Porcicoll approximately 7 hr after semen collection. The resulting sperm samples and controls were evaluated for sperm quality immediately and again after storage at 16-18°C for 4 and 7 days. Sperm recovery was 94 ± 18% and 87 ± 15% for 20% and 30% Porcicoll, respectively (p > .05). Sperm mitochondrial membrane potential and chromatin integrity were unaffected (p > .05). The proportion of live spermatozoa producing superoxide (9 ± 8%, 7 ± 6% and 3 ± 1%; p < .05), and the proportion of spermatozoa with high stainability DNA (0.68 ± 19%, 0.61 ± 0.22% and 0.96 ± 0.23%; p < .05- <0.01), were marginally increased whereas membrane integrity, although high, was lower in the centrifuged samples than in the controls (82 ± 8%, 83 ± 5% versus 92 ± 4%; p < .05). In conclusion, centrifugation through 20% or 30% Porcicoll enables most spermatozoa to be recovered, without having a major effect on sperm quality. These results are encouraging for further studies involving microbiological investigation of the processed samples, and scaling-up to process larger volumes of boar ejaculates.

Attitudes of dental practitioners towards antimicrobial therapy in Croatia and Bosnia and Herzegovina.

INTRODUCTION: The objective of this study was to assess perceptions and attitudes amongst dental practitioners in relation to antibiotic usage and antibiotic resistance. METHODS: Self-administered questionnaire was given to dental practitioners employed in south Croatia, west Herzegovina and Sarajevo, Bosnia and Herzegovina (N = 115). RESULTS: 81.7% of respondents agreed the usage of antimicrobials is frequently uncritical and unnecessary. 83.5% of dental practitioners reported that they have used guidelines in their practice; however, only 9 out of 115 stated valid guidelines. One-third of the respondents agreed or were undecided that the usage of antimicrobials in every oral inflammatory process treatment is justified. Furthermore, 13% was undecided and 26% agreed that pregnant women and breastfeeding women should not use any antimicrobials. However, three quarters of respondents considered they had satisfactory knowledge on antimicrobials. DISCUSSION: The respondents considered they had satisfactory knowledge on antimicrobials, which was in contrast to the knowledge shown, but also expressed the need for additional education. Therefore, adequate measures include the creation of the local guidelines, their implementation, and updating the practitioners' knowledge on antibiotic use and resistance through continuous educational courses.

Assessing antimicrobial misuse in small-scale chicken farms in Vietnam from an observational study.

BACKGROUND: Antimicrobials are used by poultry farmers in Vietnam as a tool to treat and prevent infectious diseases. We aimed to determine the fraction of disease episodes likely to remain untreated due to the administration of antimicrobials on non-susceptible pathogens in chicken flocks in the Mekong Delta of Vietnam. Weekly data on antimicrobial use and clinical signs were collected from 88 randomly chosen chicken flocks over 124 full production cycles (i.e. time between restocking flocks with day-old chicks and sale for slaughter). A naïve Bayes model was trained to infer the probabilities of disease episodes having been caused by each of 24 pathogens, given the observed clinical sign profile, and expert knowledge on their relative incidence. RESULTS: A total of 224 disease episodes were observed, of which 44.8% were attributed to viruses (95% CI 31.1-58.4%), 54.6% (CI 40.4-68.7%) to bacteria, and 0.6% (CI 0-1.7%) to a protozoan (Eimeria spp.). Antimicrobials were more frequently administered on weeks with disease than on weeks without disease (43.3% vs. 17.8%; p < 0.001). A median of 2 [IQR 0-4] antimicrobials were used by episode. The choice of specific antimicrobials was independent on whether the flocks had disease clinical signs or not. Antimicrobials were not used in 30.3% of the episodes. The overall probability that episodes were not effectively treated was 74.2, and 53.7% when discounting cases where the inferred aetiology is viral. Considering only episodes where antimicrobials were given, these probabilities were 57.4 and 23.8% respectively. CONCLUSIONS: This study highlights untargeted use of antimicrobials on small-scale Vietnamese chicken farms, as well as the limitations of antimicrobials as effective tools to control infectious diseases.

Veterinary medicinal product usage among food animal producers and its health implications in Central Ethiopia.

BACKGROUND: Antimicrobials and anthelmintics are the most commonly used veterinary drugs to control animal diseases. However, widespread use of these drugs could contribute to the emergence of drug resistance. Information on the practice of antimicrobial usage among food animal raising communities in Central Ethiopia is scarce. We used a standardised questionnaire survey to assess knowledge, awareness, and practices related to drug use and resistance in food animals among the farmers in and around Bishoftu town. RESULTS: Of the total of 220 livestock owners interviewed, around 80% of the respondents were not able to define what antimicrobials are and for what purposes they are used. Only 14.1% (n = 31) of the respondents had awareness about antimicrobial resistance (AMR) and its consequences; and 35.5% (n = 11/31) and 9.7% (n = 3/31) of them agreed that the irrational use of antimicrobials in animals could lead to AMR in animals and humans. Oxytetracycline was the most commonly available antibiotic in veterinary drug shops/pharmacies and the most widely used drug in the area. However, 43.3% of the respondents did not see clinical improvements after using antibiotics. Similarly, the respondents explained that no response was observed in 73.3, 70.8 and 52.5% of the cases after medication with anthelmintics, antiprotozoal and acaricides, respectively. About 56.7% of the respondents considered traditional medicines equally important to modern medicines. It was also noted that there were illegal drug vendors, dispensing medicines under unfavourable conditions which include a direct exposure to sunlight, which practice violates the drug handling and storage recommendations given by WHO. CONCLUSION: The study revealed that there is a general lack of awareness among food animal owners about the correct use of antibiotics and anthelmintics. The widespread misuse and improper drug dispensing and handling practices observed in this study can affect the drug quality and can also contribute to the development of drug resistance in central Ethiopia.