Pathogenesis
Adult lice live on the skin of the sheep, feeding on skin debris and lanolin. Subsequent irritation causes the sheep to rub and bite affected areas, resulting in damage to the skin and wool integrity (Figure 1). …show more content…
In cooler temperatures (early mornings, afternoons), lice will climb to wool fibre tips. This is prime opportunity for transmission.
Lice impact on the sheep industry
Sheep lice is a top 3 contender of the most significant parasitic disease of sheep in Australian farms. In NSW alone, the cost for treatment and control of sheep lice annually is estimated to be $81 million1.
Production losses: The stress from discomfort of lice infestation affect nutrition and feeding of the sheep resulting in major production losses1. These losses include reduction in fleece weight, staple strength, poor quality, style and yield. Irritation to the skin of the sheep also increases suint and skin secretions which in turn discolour the fleece1. In combination, the poor quality and quantity of wool produced results in major losses to the …show more content…
Generally this would cost between $2-3 per sheep1,5. NSW sheep producers spend over $30 million on chemicals p/a to treat and prevent body lice3. Farmers may also need to supply personal protective equipment, health checks and training for workers as the chemicals may pose risks to safety1.
Management strategies
Effective and proper management practices are essential in achieving long-term lice control.
Prevention of transmission/re-emergence:
Prevention is always better than having to treat for lice. Prevention limits exposure and reduces risks of transmission posed by introduced or stray sheep.
● Fencing to separate infected and clean, or shorn and unshorn flocks, and also creates buffer zones to catch stray sheep before they come into contact with your sheep1,13.
● Quarantine all sheep even if they appear free of lice infestations13. Light infestations (especially in short wool) is hard to detect.
● Ensure the knowledge of lice history of the new sheep, inspect and treat before quarantine for 6-10 months for observation1.
● Clothing, footwear, shearing equipment and sheds may be sources of lice. As precaution, decontaminate or use disposable equipment4,13.
Monitoring and detection:
Regular inspection at least once-monthly is