Barber's pole worm (Haemonchus contortus) is the most important parasite that needs to be controlled in sheep within summer rainfall areas of Australia.
Therefore, it would not be surprising if we see outbreaks of disease due to Barber's Pole worm with the warm, moist conditions we have recently experienced.
Adult Barber's pole worms live in the fourth stomach of sheep.
The mature female worms are visible to the naked eye.
The gut of the worm is red, as it is full of blood. Wound around the gut is the white ovary, packed with hundreds of eggs.
This red and white spiral effect gives the worm its name as it looks like the classic barber's pole.
The adult female worms are prolific egg producers leading rapidly to a heavy pasture contamination.
During warm, moist conditions these eggs hatch into larvae and are eaten by sheep while grazing.
Given their prolific production, worm populations can build up rapidly.
Like other internal parasites, Barber's pole worms mainly affect weaners and lactating ewes.
Barber's pole worms feed by sucking blood leading to anaemia and 'bottle jaw', but not necessarily weight loss or diarrhoea.
Just 1000 adult Barber's pole worms can remove 50ml of blood from a sheep per day.
Consequently, Barber's pole worm outbreaks can lead to high mortalities in a short space of time.
Barber's pole worms can be detected at post-mortem, or in live animals by a faecal egg count.
As with other internal parasites, producers need to be aware that drench resistance to Barber's pole worm is becoming increasingly common.
For further information please contact your local veterinarian or Agriculture Victoria veterinary or animal health officer, or in NSW your Local Land Services.