Veterinarians Without Borders

Dietary fat composition modulates host physiology and the gut microbiome, but the long-term effects of specific fat sources and the extent to which these changes resolve after dietary reversal remain incompletely defined. Here, we present a longitudinal multi-omic resource of mice maintained for one year on a purified control diet, seven high-fat diets differing in predominant fat source, or reversal regimens in which animals were switched from high-fat to control diet after 4 or 9 months. We further incorporated two cohorts with distinct pre-existing microbiome configurations to determine how baseline community structure shapes diet-induced remodeling of the gut microbiome ecosystem. By integrating longitudinal phenotyping, fecal metagenomics, fecal metabolomics, plasma metabolomics and lipidomics, and intestinal single-cell RNA sequencing, we defined the shared and dietary fat-specific responses across host and microbiome compartments. Baseline microbiome composition strongly influenced microbial responses to diet, indicating that pre-existing community structure is a major determinant of dietary ecosystem remodeling. Although many altered features shifted toward baseline after dietary reversal, only approximately half of diet-associated microbial changes recovered within the study window. A subset of taxa exhibited persistent alterations, including sustained depletion of Lactobacillus johnsonii and Bifidobacterium pseudolongum and sustained enrichment of Alistipes finegoldii, consistent with a "microbiome memory" of prior high-fat diet exposure. This memory effect is mirrored in the host, by sustained suppression of major histocompatibility complex class II (MHC-II) gene expression in intestinal epithelial cells after dietary reversal. These findings indicate that dietary fats leave a lasting imprint on the host-microbiome interactome that survives dietary intervention. Together, these data establish a resource for defining how dietary fat source, baseline microbiome composition, and dietary history shape host-microbiome states. The entire resource is available online as an RShiny app.

Hepatopathies in dogs often present diagnostic challenges due to the overlap of infectious, metabolic, and inflammatory etiologies. This report describes a case of bacterial hepatitis caused by Staphylococcus pseudintermedius associated with hepatic copper accumulation in a dog, emphasizing the diagnostic approach, clinical progression, and therapeutic management. A female dog was presented with nonspecific clinical signs and biochemical evidence of hepatocellular injury. Serial hematological and biochemical analyses revealed progressive liver enzyme alterations, prompting further diagnostic investigation. Definitive diagnosis was established through liver biopsy, histopathological evaluation, bacterial culture with antimicrobial susceptibility testing, and hepatic copper quantification. Histopathology demonstrated inflammatory changes consistent with bacterial hepatitis, along with cholestasis and hepatocellular degeneration. Microbiological culture identified Staphylococcus pseudintermedius as the causative agent. Hepatic copper concentration was markedly increased, exceeding reference limits. Targeted antimicrobial therapy and supportive hepatic treatment were initiated, resulting in progressive clinical improvement and gradual normalization of laboratory parameters during follow-up. The temporal response to therapy suggests that bacterial hepatitis was the primary condition, with secondary copper accumulation likely associated with cholestasis. However, limitations in the assessment of copper distribution prevent definitive differentiation between primary and secondary hepatopathy. This case highlights the importance of comprehensive diagnostic evaluation in canine hepatopathies and underscores the potential coexistence of infectious and metabolic factors in liver disease. Recognition of such multifactorial conditions is essential for accurate diagnosis and appropriate therapeutic decision-making in small animal practice.

Hypothyroidism in dogs is a common endocrine disorder resulting from deficient thyroid hormone production, leading to a reduced metabolic rate. A four- year-old, neutered female Shih Tzu was presented with a history of progressive weight gain, lethargy, bilateral symmetrical alopecia, and cold intolerance over the preceding three months. Physical examination revealed a dull coat, seborrhoeic dermatitis, bradycardia and mild obesity. Routine haematology and serum biochemistry were within normal limits except for mild hypercholesterolaemia. Thyroid function testing demonstrated low total thyroxine (T4) and free T4 levels with elevated thyroid-stimulating hormone (TSH), confirming primary hypothyroidism. The dog was treated with oral levothyroxine sodium at 20 µg/kg twice daily, resulting in significant clinical improvement within six weeks.

To date, there is little evidence on laparoscopic repair of peritoneopericardial diaphragmatic hernias (PPDH). The present study reports on surgical technique considerations, complications and outcome. This was a multicentric retrospective cohort study of patients with laparoscopic PPDH repairs, using low-pressure CO2 insufflation (3-4 mmHg) who were operated between October 2022 to November 2024 in two specialist centers. Dog and cat patients were diagnosed with PPDH and treated laparoscopically using low-pressure CO2 insufflation (3-4 mmHg). Patients were either symptomatic or their owners wished for repair. Demographics of patients and details of surgical procedures including follow-up were reported in simple observational statistics. Details of surgical procedures included extent of PPDH, number of ports, insufflation pressure, suture use, use of thoracocentesis with an 18 gauge needle and/or drain, operating and total surgical time, anesthetic and surgical complications during and after surgery and a follow up at 6 months. Twelve canine and one feline patient were included in the study. One case required conversion to open surgery due to CO2-induced pericardial tamponade. All patients survived and had no serious complications. Full laparoscopic repair of PPDH using low insufflation pressure was successfully achieved in 92% (12/13) patients. This is the largest case series to report on outcomes of laparoscopic repairs of PPDH. Laparoscopic treatment of PPDH is a viable option without increased risk of complications.

African swine fever (ASF) is a transboundary viral disease that has heavily impacted Southeast Asia since its introduction in 2019. Smallholder pig production systems in Cambodia and the Lao People’s Democratic Republic (the Lao PDR), characterized by low biosecurity, free-ranging practices, and limited veterinary oversight, remain particularly vulnerable. To assess farmers’ awareness and practices regarding ASF, a knowledge, attitudes, and practices (KAP) survey was implemented between March and September 2023 by Agronomes et Vétérinaires Sans Frontières within the framework of the Biosecurity in Pig Farming (BIG) project. A total of 471 pig farmers, including 56% women, were interviewed across eight provinces using a standardized questionnaire (188 in Cambodia and 283 in the Lao PDR). Results showed that ASF awareness was generally high (92% in Cambodia, 66% in the Lao PDR), yet 15% of Cambodian and 30% of Lao respondents expressed doubts about the presence of ASF in their country. While recognition of ASF symptoms was moderate and positively correlated with farmers’ perceived capacity to identify the disease, knowledge of transmission pathways was low and often misaligned with perceptions. Airborne transmission was frequently cited as a risk, and the risks related to visitors and fomites were underestimated by more than 50% of the farmers. Implementation of biosecurity measures (BSM) was limited, with mean scores of 43% in Cambodia and 27% in the Lao PDR. Risky practices such as swill feeding, free-ranging, sharing of boars, traders, and inadequate carcass disposal remained widespread. Statistical analysis identified education level, herd size, knowledge, perceived risks, and perceived benefits of BSM as the main determinants of biosecurity implementation. Farmers with larger herds or stronger commercial orientation demonstrated higher biosecurity adoption, while misconceptions and knowledge gaps remained frequent among smallholder farmers. Strengthening awareness, promoting low-cost and feasible biosecurity practices, and integrating farmer-centred approaches are essential for reducing ASF transmission risks and improving the resilience of smallholder pig production systems in the region.

Metagenomic analysis of deeply sequenced, eukaryotic-dominant symbiotic communities can be difficult for many metagenomic workflows. Here, we present MAGUS, a bioinformatic toolkit that uses a suite of custom bioinformatic methods for iterative genome assembly and filtering of pan-domain communities, where eukaryotes, bacteria, viruses, and functionally annotated gene catalogs are resolved and analyzed over a series of interconnected, modular software components. We evaluated MAGUS using deeply sequenced (median depth: 579 million reads) ten samples of hard corals, soft corals, and hydrozoans, which comprise complex, eukaryote-dominated symbiotic communities. We successfully resolved phylogenetically comparable host (N = 10), algal (N = 6), bacterial (N = 55), and viral (N = 160,925) genomes, as well as a gene catalog comprising 15,369,684 non-redundant genes (7.6% functionally annotated). MAGUS is available on GitHub (https://github.com/two-frontiers-project/2FP_MAGUS/).

XTree is a k-mer-based aligner enabling rapid, memory-efficient alignment of sequencing reads to whole-genome reference databases with up to millions of genomes. Here, we detail XTree's performance on short and long read sequencing data and demonstrate its high accuracy across diverse bacterial, viral, and eukaryotic genomes. Benchmarking demonstrates superior and/or comparable precision and recall over existing tools, with more scalable indexing and efficient memory mapping. We additionally provide pre-indexed databases, including (1) the Genome Taxonomy Database (versions r214-r226), (2) representative GenBank fungi and protozoan genomes and (3) the Pan-Viral-Compendium, a bespoke data resource spanning 6.6 million, quality-controlled, viral genomes.

The interface between wild boar and domestic pigs represents is a critical hotspot for the spillover and spillback of several diseases, including brucellosis. This cross-sectional study assessed the seroprevalence of Brucella spp. and B. suis in swine at the wildlife-livestock interface in northeast Portugal, focusing on wild boar and the autochthonous Bísaro pig breed. Antibodies against Brucella spp. were detected in 25.7 % of wild boar (95/370; 95 % CI: 21.2 %-30.1 %) and 15.2 % of Bísaro pigs (35/231; 95 % CI: 10.5 %-19.8 %). Among these, 82 wild boar and 33 domestic pigs tested positive for B. suis, with molecular confirmation in three domestic pigs, marking the first molecular identification of B. suis in Bísaro pigs. Spatial analysis revealed distinct B. suis prevalence, higher in wild boar in the northwest and in domestic pigs in the southeast. A significant positive correlation between the spatial distributions suggests potential transmission at the wildlife-livestock interface. Environmental and anthropogenic factors showed moderate correlation with B. suis prevalence, suggesting a link to animals' overpopulation. Additionally, prevalence was positively associated with pig farms land elevation and negatively with dense shrublands coverage/areas, reinforcing the role of farming practices in pathogen spillover. These findings highlight the multifactorial nature of B. suis distribution, shaped by both ecological and human-driven landscape features. Given the zoonotic potential, this study underscores the urgent need for integrated One Health surveillance and control strategies to mitigate public health risks in rural communities and safeguard animal and human health at both regional and national level.

The French Armed Forces are regularly deployed in areas of endemic rabies, a virus responsible for 59,000 deaths worldwide per year. During Operation DAMAN 50 at the end of 2024, rapid conflict intensification in southern Lebanon at once significantly increased the rabies exposure of French servicemen and decreased access to laboratory analyses. Exposures of military personnel to scratches from cats of unknown rabies status multiplied, putting post-exposure prophylaxis (PEP) stocks under extreme strain. To minimize the risk of a PEP shortage and its consequences, the medical personnel deployed in Operation DAMAN 50 adopted a pragmatic strategy updating existing recommendations. At the individual level, watch-and-see PEP occurred only when veterinary cat observation was possible. In the absence of reliable laboratory service, it was based on pathophysiological, epidemiological, environmental and operational data. On a wider scale, the strategy involved controlling the feline population. Based on the clinical field skills and global appraisal of situations not previously encountered by military practitioners, operational capacity was maintained, while limited vaccine supplies were reserved for patients in dire need.

This thesis investigates the amyloid-like oligomerization of Golgi-associated plant pathogenesis-related protein 1 (GAPR-1), a unique member of the CAP superfamily, and its functional role in regulating autophagy through interaction with beclin 1. The study aims to elucidate how membrane binding and oligomerization of GAPR-1 are governed by specific lipid interactions and structural determinants. A multidisciplinary approach integrating molecular dynamics simulations, biochemical assays, and yeast model systems was used to elucidate the molecular mechanisms underlying GAPR-1 function. The findings show that GAPR-1 binds negatively charged lipids in a tilted orientation. This orientation is mediated by Lys7 and N-terminal myristoylation, which is essential for its subsequent oligomerization and interaction with beclin 1. Lysine residues in the N-terminal α-helix modulate the kinetics of oligomerization and biomolecular condensation. GAPR-1 binds multiple lipids through an extended interface rather than a defined pocket. The amphipathic N-terminal α-helix likely facilitates the subsequent membrane insertion and stabilization. Mutational analyses revealed that specific residues and dimer configurations regulate membrane docking, amyloid-like aggregation, and condensate dynamics. Furthermore, the study highlights the distinct regulatory roles of GAPR-1 and Bcl-2 in modulating beclin 1 activity, demonstrating that both proteins inhibit autophagy through independent but complementary pathways. This work not only advances our understanding of how peripheral membrane proteins couple lipid binding to functional assembly, but also establishes Saccharomyces cerevisiae as a model system for studying amyloid oligomers and their functions. These insights offer implications for novel disease intervention strategies via regulation of autophagy with possibly even broader implications for targeting amyloid-related diseases, including neurodegeneration and cancer.