Clouds and Pasteurella multocida

The University of Queensland

  • Project code: PRJ-010276

  • Project stage: Closed

  • Project start date: Wednesday, August 3, 2016

  • Project completion date: Wednesday, April 1, 2020

  • National Priority: CME-Priority 3-Contributing to efficient and secure chicken production systems

Summary

Fowl cholera continues to be a problem in broiler breeder operations and has emerged in organic and free range broiler production. With RIRDC and CRC funding, a series of diagnostic tools have been developed and are currently delivered via a user pays service by the Microbiology Research Group within QAAFI. These diagnostic tools along with supporting molecular assays have been used to look at the genetic diversity within a fowl cholera outbreak and then that confirm the identification of the isolate as Pasteurella multocida and then identify the lipopolysaccharide genotype via PCR. However, these tools only look at a very limited amount of the genome and therefore provide little information about the impact of diversity between isolates on key issues such as immunogenic surface structures and virulence factors. In human medicine, the importance of genetic variation within a pathogen (the concept of a “cloud” as opposed to a single species or indeed a single clone) within an individual is now being recognised as a critical issue. For example, Burkeholderia dolosa isolates within a cystic fibrosis patient show genetic variation over time in genes involved with outer-membrane components, iron scavenging and antimicrobial resistance (Nature Genetics 46:82-87). Indeed, the important and impact of “clouds” of viruses is well appreciated in poultry vaccines and poultry diseases. This proposal seeks to establish the importance of clouds in disease outbreaks associated with fowl cholera. A knowledge of the impact of “clouds” will allow a more informed and more targtted use of vaccines and biosecurity programs.

Program

Chicken Meat

Research Organisation

The University of Queensland

Objective Summary

1. Establish a pipeline to allow effective rapid whole genome sequencing and then full bio-informatic analysis to be able to understand and measure genetic diversity within a disease outbreak.
2. Use the above pipeline and analysis approach on a well characterized and extensive collection of Pasteurella multocida from a prolonged fowl cholera outbreak (including the various killed vaccine strains used over the period of the outbreak).
3. Use the sequencing and bioinformatics analysis to understand the contribution of clouds (genetic diversity) to evasion of vaccine protection and to thus assist in ensuring a match between vaccine protection and field challenge.
4. Transfer the established technologies to the user pays service provided by the Microbiology Research Group for on-going use by the poultry industry beyond the life of the project.