Distribution of indole-producing urease-negative pasteurellas in animals

Area of Science:

• Veterinary Microbiology
• Bacterial Taxonomy
• Animal Health

Background:

• The genus Pasteurella encompasses diverse bacterial species significant in animal health.
• Previous classification grouped many indole-positive, urease-negative Pasteurella under Pasteurella multocida.
• Recent taxonomic revisions have introduced new subspecies and species within the Pasteurella genus.

Purpose of the Study:

• To re-evaluate indole-positive, urease-negative Pasteurella animal isolates using current taxonomic classifications.
• To determine the prevalence of recognized Pasteurella multocida subspecies and related species in animal populations.
• To identify and characterize unassignable isolates and investigate host-specific predilections.

Main Methods:

• Phenotypic characterization of 356 animal Pasteurella isolates.
• Comparison of isolate profiles against established taxa: P. multocida ssp. multocida, P. multocida ssp. septica, P. multocida ssp. gallicida, P. canis, P. stomatis/Taxon 16, and Pasteurella sp. B.
• Analysis of isolation sources, animal species, and host-specific patterns.

Main Results:

• 263 (73.9%) of the 356 isolates were assigned to known taxa, with P. multocida ssp. multocida being the most frequent overall.
• 93 isolates (26.1%) represented 17 distinct unassignable biotypes.
• P. canis was predominant in dogs, P. multocida ssp. septica showed host predilection for cats (especially CNS infections), and P. canis for sheep. Unassignable biotypes showed predilection for cattle and dogs.

Conclusions:

• The current classification successfully identified a majority of indole-positive, urease-negative Pasteurella animal isolates.
• A significant proportion of isolates represent novel biotypes, indicating ongoing evolution and diversity within the Pasteurella genus.
• Specific Pasteurella taxa exhibit distinct host predilections and tissue tropisms, relevant for understanding animal disease pathogenesis.