Abstract
Nanopore-based sequencing has emerged as a revolutionary tool for animal pathogen genomics, offering capabilities unattainable with Sanger and next-generation sequencing (NGS). Despite rapid technical progress, routine veterinary deployment still faces uncertainty in study design, sample preparation, and interpretation thresholds across diverse hosts and sample matrices. Accordingly, this review consolidates recent evidence and provides workflow-oriented guidance for veterinary diagnostics and One Health surveillance. Its portability, ability to generate real-time long-read data, and minimal infrastructure requirements enable rapid, on-site sequencing for veterinary diagnostics and surveillance. This review examines the principles of nanopore sequencing and its advantages over conventional methods, surveying recent applications across viral, bacterial (including antimicrobial resistance, AMR), and parasitic pathogen detection in animals. In viral diagnostics, it facilitates rapid whole-genome sequencing and outbreak tracing in field settings. For bacterial pathogens, it enables near-complete genome assembly and identification of plasmid-borne AMR genes. Emerging studies also demonstrate its utility in parasitology, from high-resolution species identification to whole-genome assemblies. We compare these advancements with traditional diagnostics, highlighting strengths in speed and comprehensiveness while addressing current limitations in accuracy and host-DNA interference. As technology matures through improvements in chemistry and adaptive sampling, nanopore sequencing is poised to transform veterinary pathogen detection and bolster One Health surveillance of emerging zoonoses.