Strategic and novel approaches to reducing flystrike in sheep

Summary

Flystrike is well recognised as a continuing issue for sheep in every production environment. In addition to the large economic cost, flystrike is a serious animal welfare issue.

A review of the current state of knowledge of flystrike was conducted, including a review of developing technologies that may assist in its elimination.

An integrated portfolio of work outlined in the final report provides producers with the tools and information necessary to reduce the incidence and prevalence of flystrike. The portfolio is made up of breeding non-susceptible sheep, implementing resilient management systems and reliable insect control methods through cautious use of chemicals.

Objectives

This project conducted an extensive review of flystrike control and
technological developments to produce a new strategy for the sheep industry that identifies future pathways of investigation that are likely to provide the greatest impact.

Key findings

The review demonstrates that significant investment has been made in understanding the sheep genetic factors associated with flystrike, but that further work is needed to apply this information to industry. This work includes:

Immediate solutions (1-3 years)

• chemical management to enhance the awareness and availability of chemical resistance tests for flies

• a fly-free farming industry campaign to achieve widespread adoption of current and future technological interventions

• improved identification of affected animals to improve treatment time

• improved management of affected animals to minimise mortality, pain and suffering, and improve recovery times.

Medium-term solutions (3-8 years)

• breeding sheep that are less susceptible to fly strike through better use of breeding values and building more comprehensive genetic resource databases

• climate change modelling to predict the likely impact of breech and body strike in the future

• enhancing predictive capacity through automated fly monitoring and region-based predictions of flystrike

• building integrated pest management systems to enhance the efficacy of individual control strategies.  

Longer-term solutions (5-15 years)

• expert panel and strategic review teams to define research areas that need to be completed

• manipulating the insect to reduce the population of the species

• understanding the complex biology of the host-parasite relationship.

Benefits to industry

Reducing flystrike by non-chemical, non-surgical means has the triple impact of improving welfare, reducing chemical use and ensuring sustainable and ethical production of sheep in Australia.

MLA action

MLA continues to promote the use of ASBVs for breech traits (wrinkle, cover and dags) that will reduce flystrike incidence. Further research aims to reduce the prevalence of sheep blowfly in order to solve the flystrike issue without the need for surgical treatments or excessive use of chemicals.

Future research

A short to medium term investment portfolio is proposed for the Australian sheep industry to fight against flystrike in the future. Future investments should focus on:

• Non-susceptible sheep – A series of projects that focus on breeding genotypes that become less prone to flystrike over time.
• Resilient management systems – Providing producers with the necessary information and knowledge to reduce flystrike to zero on their properties.
• Reliable insect control methods - Gathering a complete understanding of the usefulness of current chemicals and application methods and ensuring that chemicals remain effective whilst reducing excessive reliance on such chemicals.