DPIRD supervising livestock compliance inspector Richard Ward said flystrike was a serious welfare concern in sheep and also impacted the productivity of the affected animal.
“Flystrike is caused by blowfly feeding on the skin of sheep that has become soaked by urine, faeces, or wet wool,” Mr Ward said.
“The risk of flystrike increases when the ambient temperature increases (above 15°C), wind speeds are moderate and sheep fleece remains moist from rainfall for several days.”
Mr Ward said animal welfare reports of struck animals occurred more often during spring and autumn.
“It is not acceptable to leave struck sheep untreated,” Mr Ward said.
“During high-risk periods sheep should be inspected every two days, and we recommend that producers are proactive in managing the risk in their flock.”
Signs to watch for include animals separating from the mob, reduced grazing, rapid waggling of the tail, discoloured wool and trying to bite or reach affected sites.
“For struck sheep, the affected area should be clipped with clean margins of at least 5cm surrounding the site and a registered chemical dressing applied,” Mr Ward said.
“The clipped wool should be sealed in a plastic bag and left in the sun to kill any maggots before disposal.”
Mr Ward said it was important for producers to treat sheep showing signs of flystrike promptly and not transport them to saleyards while infested.
“It is an offence under the Animal Welfare Transport Regulations to transport sheep with a prescribed condition such as flystrike,” Mr Ward said.
Livestock development officer Katherine Davies said preventative measures producers could take included worm control to reduce scouring, strategic chemical application and timing shearing and crutching before high-risk periods.
The department’s free Flystrike Assist app is a valuable tool to help producers identify a chemical’s protection period and manage the strict wool, meat and export withholding periods for both treatment and prevention.
The FlyBoss website (flybosstools.com.au) also has a number of tools to assist wool producers to treat individual sheep or the whole flock, as well as decision support tools to identify high-risk flystrike periods and create management plans.
“Longer term preventative options are aimed at reducing the number of susceptible sheep in the flock,” Ms Davies said.
“This includes genetic selection to reduce body wrinkle, breech wrinkle, dag and breech cover scores, and making sure tails are docked at the correct length to reduce dag formation and urine staining.
“These longer-term options should be used in conjunction with strategically timed shearing and crutching, effective chemical application, paddock selection, management of scouring, dags and stain, and reducing the fly population.”
