A Systematic Review on the Link between Animal Welfare and Antimicrobial Use in Captive Animals

Fecal microbiota transplants facilitate post-antibiotic recovery of gut microbiota in cheetahs (Acinonyx jubatus)

Burgeoning study of host-associated microbiomes has accelerated the development of microbial therapies, including fecal microbiota transplants (FMTs). FMTs provide host-specific microbial supplementation, with applicability across host species. Studying FMTs can simultaneously provide comparative frameworks for understanding microbial therapies in diverse microbial systems and improve the health of managed wildlife. Ex-situ carnivores, including cheetahs (Acinonyx jubatus), often suffer from intractable gut infections similar to those treated with antibiotics and FMTs in humans, providing a valuable system for testing FMT efficacy. Using an experimental approach in 21 cheetahs, we tested whether autologous FMTs facilitated post-antibiotic recovery of gut microbiota. We used 16S rRNA sequencing and microbial source tracking to characterize antibiotic-induced microbial extirpations and signatures of FMT engraftment for single versus multiple FMTs. We found that antibiotics extirpated abundant bacteria and FMTs quickened post-antibiotic recovery via engraftment of bacteria that may facilitate protein digestion and butyrate production (Fusobacterium). Although multiple FMTs better sustained microbial recovery compared to a single FMT, one FMT improved recovery compared to antibiotics alone. This study elucidated the dynamics of microbiome modulation in a non-model system and improves foundations for reproducible, low-cost, low-dose, and minimally invasive FMT protocols, emphasizing the scientific and applied value of FMTs across species.

Reduced antimicrobial use in weaned pigs through an intervention program supporting veterinarians' adherence to the clinical practice Streptococcus suis guideline

Veterinary guidelines have been published in the Netherlands to promote antimicrobial stewardship. An evidence-based intervention program using Implementation Mapping and performance indicators was developed to enhance veterinarians' adherence to the veterinary guideline "Streptococcus suis in weaned pigs". The present study evaluates the effect of this eight-month intervention program in a multicenter, pragmatic, stepped-wedge cluster design trial. Of the 49 veterinarians that participated, 33 provided data from 125 S. suis problem farms. A baseline measurement (M0) before the intervention program, and two measurements during (M1) and partly after (M2) the intervention program were conducted. A significant reduction in farm-level antimicrobial use of 25% in M1 and 49% in M2 was achieved compared to M0. For the performance indicators at veterinarian level, a significant reduction (- 36%) was found for antimicrobial prescription in M2, a significant increase occurred in argumentation for 2nd choice antimicrobials (M2) and the usage of bacteriological examination (M1). Two other performance indicators (ratio of 1st to 2nd or 3rd choice antimicrobials and corticosteroids) did not change significantly. These results show how an evidence-based intervention program to foster adherence to an existing veterinary clinical practice guideline achieved a significant reduction in antimicrobial prescriptions by swine veterinarians.

The correlation between on-farm biosecurity and animal welfare indices in large-scale turkey production

This research aimed to determine the association between biosecurity and animal welfare measures in large-scale fattening turkey farms in Hungary. Large-scale farms raising male fattening turkeys across Hungary were contacted, with 24 agreeing to participate. The Biocheck.UGent questionnaire was used to evaluate biosecurity measures, and Animal Welfare Indicators (AWIN) protocol was used for welfare assessment. The association between biosecurity and welfare indicators was investigated by correlation testing and prediction accuracy using random forest classification. The areas of biosecurity that were shown to be closely linked to the welfare index were the organization of the farm (farm management, supply of materials), the control and hygienic measures implemented between farm structures, cleaning and disinfection measures on the farm, and control and hygienic measures implemented in the case of farm workers and visitors upon entrance and exit. The study highlighted the link between biosecurity and animal welfare in turkey production, concluding that enhanced biosecurity measures correlate with better welfare outcomes and emphasizing the need for comprehensive and well-implemented biosecurity protocols.

Conventionally Reared Wallon Meat Lambs Carry Transiently Multi-Drug-Resistant Escherichia coli with Reduced Sensitivity to Colistin Before Slaughter

Major efforts have been made to reduce the use of colistin in livestock since the discovery of the plasmid-borne mobile colistin resistance (mcr) gene in E. coli a decade ago, to curb the burden of its potential transmission to other bacterial species, spread between animals, humans and the environment. This study explored the longitudinal prevalence and characteristics of colistin-resistant and extended-spectrum beta-lactamase-producing (ESBL) E. coli via in vivo fecal and ex vivo carcass swabs from two batches of conventional indoor and organic outdoor Wallon meat sheep from birth to slaughter in 2020 and 2021. Antimicrobial susceptibility testing via broth microdilution revealed that n = 16/109 (15%) E. coli isolates from conventional meat lamb fecal samples had a reduced colistin sensitivity (MIC = 0.5 μg/mL) and thereof, n = 9/109 (8%) were multi-drug-resistant E. coli, while no resistant isolates were recovered from their carcasses. Sequencing revealed causative pmrB genes, indicating that the reduced sensitivity to colistin was not plasmid-borne. While the sample size was small (n = 32), no colistin-resistant and ESBL-producing E. coli were isolated from the organic meat sheep and their carcasses, potentially due to the different husbandry conditions. Prudent and judicious antimicrobial use and strict slaughter hygiene remain imperative for effective risk management to protect consumers in a sustainable One Health approach.

A comparison of antibiotic resistance genes and mobile genetic elements in wild and captive Himalayan vultures

As the most widely distributed scavenger birds on the Qinghai-Tibetan Plateau, Himalayan vultures (Gyps himalayensis) feed on the carcasses of various wild and domestic animals, facing the dual selection pressure of pathogens and antibiotics and are suitable biological sentinel species for monitoring antibiotic resistance genes (ARGs). This study used metagenomic sequencing to comparatively investigate the ARGs and mobile genetic elements (MGEs) of wild and captive Himalayan vultures. Overall, the resistome of Himalayan vultures contained 414 ARG subtypes resistant to 20 ARG types, with abundances ranging from 0.01 to 1,493.60 ppm. The most abundant resistance type was beta-lactam (175 subtypes), followed by multidrug resistance genes with 68 subtypes. Decreases in the abundance of macrolide-lincosamide-streptogramin (MLS) resistance genes were observed in the wild group compared with the zoo group. A total of 75 genera (five phyla) of bacteria were predicted to be the hosts of ARGs in Himalayan vultures, and the clinical (102 ARGs) and high-risk ARGs (35 Rank I and 56 Rank II ARGs) were also analyzed. Among these ARGs, twenty-two clinical ARGs, nine Rank I ARG subtypes, sixteen Rank II ARG subtypes were found to differ significantly between the two groups. Five types of MGEs (128 subtypes) were found in Himalayan vultures. Plasmids (62 subtypes) and transposases (44 subtypes) were found to be the main MGE types. Efflux pump and antibiotic deactivation were the main resistance mechanisms of ARGs in Himalayan vultures. Decreases in the abundance of cellular protection were identified in wild Himalayan vultures compared with the captive Himalayan vultures. Procrustes analysis and the co-occurrence networks analysis revealed different patterns of correlations among gut microbes, ARGs, and MGEs in wild and captive Himalayan vultures. This study is the first step in describing the characterization of the ARGs in the gut of Himalayan vultures and highlights the need to pay more attention to scavenging birds.

Animal board invited review: Improving animal health and welfare in the transition of livestock farming systems: Towards social acceptability and sustainability

The need to integrate more clearly societal expectations on livestock farming has led the authors of this article to consider that livestock farming systems must be redesigned to position health and welfare at the heart of their objectives. This article proposes a vision of the advances in knowledge required at different scales to contribute to this transformation. After defining health and welfare of animals, the article emphasises the need to consider health in a broader perspective, to deepen the question of positive emotional experiences regarding welfare, and raises the question of how to assess these two elements on farms. The positive interactions between health and welfare are presented. Some possible tensions between them are also discussed, in particular when improving welfare by providing a more stimulating and richer environment such as access to outdoor increases the risk of infectious diseases. Jointly improving health and welfare of animals poses a number of questions at various scales, from the animal level to the production chain. At the animal level, the authors highlight the need to explore: the long-term links between better welfare and physiological balance, the role of microbiota, the psycho-neuro-endocrine mechanisms linking positive mental state and health, and the trade-off between the physiological functions of production, reproduction and immunity. At the farm level, in addition to studying the relationships at the group level between welfare, health and production, the paper supports the idea of co-constructing innovative systems with livestock farmers, as well as analysing the cost, acceptability and impact of improved systems on their working conditions and well-being. At the production chain or territory levels, various questions are raised. These include studying the best strategies to improve animal health and welfare while preserving economic viability, the labelling of products and the consumers' willingness to pay, the consequences of heterogeneity in animal traits on the processing of animal products, and the spatial distribution of livestock farming and the organisation of the production and value chain. At the level of the citizen and consumer, one of the challenges is to better inter-relate sanitary and health perspectives on the one hand, and welfare concerns on the other hand. There is also a need to improve citizens' knowledge on livestock farming, and to develop more intense and constructive exchanges between livestock farmers, the livestock industry and citizens. These difficult issues plead for interdisciplinary and transdisciplinary research involving various scientific disciplines and the different stakeholders, including public policy makers through participatory research.

Antimicrobial resistance of commensal Escherichia coli and Enterococcus faecalis isolated from clinically healthy captive wild animals in Seoul zoo

Despite the importance of antimicrobial resistance, only a few studies on the antimicrobial susceptibility on wild animals have been conducted owing to their population, accessibility, and characteristics. The objective of this study was to investigate the prevalence and characteristics of antimicrobial resistance pattern in Escherichia coli and Enterococcus faecalis isolated from the feces of captive wild animals in a zoo. A total of 61 captive wild animals were included in this study. E. coli was isolated from 58 of the 61 animals and E. faecalis was isolated from 29 animals. Among the isolated E. coli strains, ampicillin exhibited the highest resistance rate (27/29, 93.1%). Of these, 18 strains (18/29, 62%) showed multidrug resistance. The multilocus sequence typing (MLST) test showed that only ST155 was detected twice, while the other 16 strains showed different ST types. Among the E. faecalis strains, two were susceptible to all tested antimicrobials, whereas the remaining 27 strains showed resistance to one or more antimicrobials. Nine strains (9/27, 31%) showed multidrug resistance. Among the E. faecalis strains, resistance to quinupristin/dalfopristin was the highest at 96.3% (26/27), while the MLST of the nine MDR strains showed no predominant ST. Genetic association with human isolates or livestock products was observed in the isolated ST types. This indicates that antibiotic resistance in the zoo is responsible for the use of antibiotics and the partial horizontal transmission between humans and animals through feeding or contact.

Global trends in antimicrobial resistance on organic and conventional farms

The important hypothesis that organic livestock management reduces the prevalence of antimicrobial resistance is either fiercely supported or bitterly contested. Yet, empirical evidence supporting this view remains fragmentary, in part because relationships between antimicrobial use and drug resistance vary dramatically across contexts, hosts, pathogens, and country-specific regulations. Here, we synthesize global policies and definitions of 'organic' and ask if organic farming results in notable reductions in the prevalence of antimicrobial resistance when directly examined alongside conventional analogs. We synthesized the results of 72 studies, spanning 22 countries and five pathogens. Our results highlight substantial variations in country-specific policies on drug use and definitions of 'organic' that hinder broad-scale and generalizable patterns. Overall, conventional farms had slightly higher levels of antimicrobial resistance (28%) relative to organic counterparts (18%), although we found significant context-dependent variation in this pattern. Notably, environmental samples from organic and conventional farms often exhibited high levels of resistance to medically important drugs, underscoring the need for more stringent and consistent policies to control antimicrobial contaminants in the soil (particularly on organic farms, where the application of conventional manure could faciliate the spread antimicrobial resistance). Taken together, these results emphasize the challenges inherent in understanding links between drug use and drug resistance, the critical need for global standards governing organic policies, and greater investment in viable alternatives for managing disease in livestock.

Attitudes towards Use of High-Importance Antimicrobials—A Cross-Sectional Study of Australian Veterinarians

The timely implementation of antimicrobial stewardship interventions could delay or prevent the development of higher levels of antimicrobial resistance in the future. In food-producing animals in Australia, high-importance antimicrobials, as rated by the Australian Strategic and Technical Advisory Group (ASTAG), include virginiamycin and third-generation cephalosporins (in individual pigs or cattle). The use of high-importance antimicrobials in companion animals is more widespread and less regulated. There is no national antimicrobial use surveillance system for animals in Australia. Consequently, there is a gap in the knowledge about reasonable use across all sectors of veterinary practice. This study explored attitudes towards the use in veterinary medicine of antimicrobials with high importance to human health, and determined levels of agreement about the introduction of restrictions or other conditions on this use. An online survey was distributed via social media and email from June to December 2020 to veterinarians working in Australia. Of the 278 respondents working in clinical practice, 49% had heard of the ASTAG rating system, and 22% used a traffic light system for antimicrobial importance in their practice. Overall, 61% of participants disagreed that veterinarians should be able to prescribe high-importance antimicrobials without restrictions. If there were to be restrictions, there was most agreement amongst all respondents for only restricting high-importance antimicrobials (73%). There is a need for education, guidance, and practical support for veterinarians for prescribing high-importance antimicrobials alongside any restrictions.