Parasite Treatment

The most common roundworms are ostertagia ostertagi, which live in the abomasum, and cooperia oncophora, which inhabit the small intestine.

Clinical disease – loss of appetite, scouring and poor condition – is generally only seen in young calves during their first grazing season when control has been inadequate.

Cattle do acquire immunity when exposed to roundworms, but it can take up to two grazing seasons.

Top tips for control

1. Identify risk

a. Younger cattle are highest risk

b. Permanent grazed pasture is highest risk

c. Larval worms accumulate throughout the grazing season

d. Young cattle not treated at housing are at risk later in the winter

2. Treat appropriately

a. Wormers should be targeted at individuals or groups at appropriate times

b. Strategic treatments can be used

c. Treatment at housing can minimise risk later in winter

3. Avoid resistance

a. Use wormers correctly