In vitro culture of buffalo fly and infections with Wolbachia
The In vitro culture of buffalo fly and infections with Wolbachia project developed an in vitro buffalo fly colony and cell line to assist in investigating new control options to combat buffalo fly infestations in cattle using Wolbachia.
Summary
Buffalo fly, Haematobia (irritans) exigua infestations are consistently listed by northern beef and dairy producers as amongst their main cattle health problems. They cause irritation to cattle, reduce weight gains and decrease milk production. They also vector a filarial nematode Stephanofilaria sp. that causes skin lesions, downgrading skin quality and raising welfare concerns. In recent years buffalo flies have dispersed southwards and westwards and their range is projected to extend significantly with climate change.
Research into new methods of buffalo fly control has been limited by the need to maintain live cattle hosts. This is expensive, severely restricts the type of research that can be conducted and is increasingly problematic from an animal ethics standpoint.
This project has developed an in vitro rearing technique for buffalo fly whereby all stages can be grown in the laboratory without the need for a live animal host. The current strain has now been maintained for 33 generations. Availability of this strain will help maintain or improve the efficiency of currently available control methods, for example through provision of a characterised and consistent strain of flies for use in
studies to detect and monitor resistance and for use in testing new candidate control compounds. It will also facilitate the development of potential new approaches to control such as techniques incorporating the use of Wolbachia and other biocontrols and the release of genetically modified strains.
We have also developed the first ever Haematobia irritans and H. exigua cell lines. Although the H. exigua cell line was lost during the Brisbane floods we expect that we will be able to re-establish this line using the method utilised successfully for H. irritans. These cell lines will be critical to attempts to transfect Wolbachia into buffalo fly. They will also provide an important research resource in areas such as early
screening and clarification of modes of action of new biocidal molecules, the use of viruses and baculoviruses for biocontrol, vaccine design, clarification of gene action and elaboration of intracellular biochemical pathways. Our finding that Wolbachia is not present in H. exigua, but is ubiquitous in closely related H. irritans suggests that H. exigua might also be a competent host for Wolbachia and indicates that investigation of this organism as a basis for new control strategies for buffalo fly is warranted.
When: 1 March 2010 to 30 May 2013
Contact: Peter James
Collaborator: Queensland Alliance for Agriculture & Food Innovation
More information
To learn more about this project, please read the final report summary and download the final report (B.NBP.0488) (PDF, 2.0 MB) from Meat & Livestock Australia.