Whole-Genome Sequencing Unravels Virulence and Antimicrobial Resistance Landscapes of Major Bovine Respiratory Disease Pathogens

Bovine respiratory diseases are a seasonally highly prevalent infectious condition and cause great economic losses to the farming industry. In order to expand the genomic database information of bovine respiratory disease pathogens, the raw data were assembled and genome annotated using relevant bioinformatics analysis software to clarify the strain virulence, resistance gene carriage, and evolution of bovine-origin Pasteurella multocida, Mannheimia haemolytica, and Mycoplasma bovis. Whole genome sequencing of Pasteurella multocida (Pm1), Mannheimia haemolytica (Mh1), and Mycoplasma bovis (Mb1) isolated from diseased material was carried out using Illumina HiSeq X and Oxford Nanopore sequencing platforms. The whole genome size of Pm1, Mh1, and Mb1 is 620,451, 2,718,449, and 1,006,140 base pairs (bp), and the GC content is 40.25%, 41.07%, and 29.29%, respectively. Additionally, in Pm1, Mh1, and Mb1, the Cluster of Orthologous Groups (COG) in the database has the largest number of annotated genes, which are the annotated Pm1 (2020), Mh1 (2058), and Mb1 (1063) genes. Whereas, the number of genes annotated in the Comprehensive Antibiotic Resistance Database (CARD) is the lowest, with 50, 97, and 5 genes. This study, through whole-genome sequencing and annotation of Pm1, Mh1, and Mb1, has enriched the gene pool of bovine respiratory disease pathogens. It contributes to a more comprehensive understanding of the genomic structure, functional gene distribution, and evolutionary relationships of these pathogens. The findings can support precise diagnosis and personalized treatment of bovine respiratory diseases, as well as help to develop targeted use of antibiotics for farm animals, thereby reducing the occurrence and spread of drug resistance. This research holds significant importance for promoting the healthy development of the livestock industry and mitigating economic losses.