Flystrike in sheep
AS WINTER draws to a close, the challenges of spring are keeping sheep farmers busy.
With the warmer days, the Department of Primary Industries (DPI) is warning producers to be on the lookout for flystrike.
The first 'fly waves' occur a fortnight after the soil temperature rises above 15 C so flystrike is usually first seen in early to mid October but varies across the State.
DPI sheep health veterinary officer Natarsha Williams said a regular inspection of all mobs was vital.
"In Victoria, scouring and dags are the major risk factor for breech strike; there have been a lot of reports of dirty sheep after this winter," she said.
"The most common cause has been high worm burdens, with sheep being rapidly re-infected after drenching from heavily contaminated pastures.
"This has resulted in many 'daggy' sheep, causing a marked increase in susceptibility to breech flystrike.
"Simple management tools to help prevent breech strike include controlling worm burdens by monitoring faecal egg counts and drenching as needed.
"Crutching ideally before flies become a problem and timely shearing can also significantly reduce the likelihood of strike."
Body strike is more likely to occur when sheep have fleece rot or dermatitis (also called "lumpy wool" or "dermo").
Dr Williams said simple measures like avoiding mustering and close contact between wet sheep would help to reduce the spread of dermatitis.
"When dipping, use a clean dip with a bacteriostatic agent added which will help to reduce the spread of the infection, plus dip young sheep first and any sheep with dermatitis last," she said.
Fleece rot tends to occur when sheep stay wet for extended periods in a humid climate and is difficult to control.
DPI advises producers to speak to a veterinarian to discuss the best treatment for these conditions.
Belly strike is more likely in sheep with footrot.
Footrot-infected sheep frequently have moist and smelly feet, and when they lie down, the moisture from their feet touches the wool and makes it wet and odorous, consequently attracting flies.
Dr Williams said prevention was always better than a cure for flystrike.
"As well as the standard management tools mentioned earlier, preventative chemical treatment may be considered to help protect sheep from flystrike," she said.
"Application of preventative chemical can provide good protection throughout the spring and even reduce the fly pressure into summer."