Grazing management – Victoria

Sheep and goats carry the same worms. When grazed together, goats carry heavier worm burdens than do sheep, especially in the absence of browse.

It is best to not run sheep and goats together, except in the pastoral zone where worms are not as important and where goats have access to browse, which they prefer. If you do run both goats and sheep in higher rainfall zones, run goats on different areas of the property from sheep. Goats also share common worms with alpacas. Goats can be successfully run with horses and cattle.

Grazing management techniques that reduce the exposure of goats to worms are based on these four steps:

• Avoid grazing on paddocks heavily contaminated with worm larvae.
• Reduce contamination of paddocks with worm eggs.
• Allow time for most of the eggs and larvae on the pasture to die.
• Where possible, provide adequate browse.

If these practices are not practical then consider feedlotting and ensure that feeders and waterers are designed to avoid faecal contamination.

Which goats are most susceptible to worms?

• Weaners in the months after weaning until about 18 months of age, when they develop a higher level of worm immunity. Paddocks used by young goats should be of the highest quality pasture as the first priority, ideally they should also be of low worm-risk. Bucks remain as susceptible as young goats.
• Late pregnant and lactating does are highly susceptible to worms as their worm immunity is reduced in late pregnancy and through early lactation. This can contribute to the seasonal increase in worm numbers and later infection of kids at foot.
• Adult or not lactating (dry) goats remain susceptible to worms as their immunity develops more slowly than it does in sheep, and is often incomplete.
• Rangeland goats moving into higher rainfall areas are highly susceptible to worms as they have little experience of worm infection and hence their immunity is poorly developed. Paddocks used by these goats should be of low worm-risk.

How are low worm-risk weaner paddocks prepared?

Weaners are the class of goat most susceptible to worms, especially as they go through their first winter. Paddocks used by weaners in late autumn and winter should be of the highest quality pasture as the first priority, ideally, they should also be of low worm-risk. Pastures grazed by weaners after the autumn break should be the lowest worm-risk on the farm. This will give those weaners a good start, in many cases allowing them to build immunity without suffering high initial worm burdens.

On winter weaner paddocks, contamination from worm eggs arises from two key periods. Most contamination occurs in late summer and autumn, however about 40% can come from worm egg deposition during late spring and early summer. Routinely giving a summer drench in November/December greatly reduces the late spring/early summer contamination.

Preparing a winter weaning paddock with ‘Smart Grazing’

The paddock(s) that will be used by weaners after the autumn break should previously only be grazed by goats* or sheep that have received an effective summer drench, or adult cattle (over 12 months old). To minimise contamination with worm eggs, graze only for 30 days after each drench is given. A similar stocking rate to the continuous stocking will be achieved by stocking at 2½–3 times your normal stocking rate.

If there is excess feed, the summer drenches can be ‘staggered’ for different mobs so as to provide a longer intensive grazing period, as removing excess feed enhances the kill of worm larvae with the summer heat.

Give the weaners an effective drench before they enter the ‘Smart grazed’ paddock after the autumn break. 

Smart grazing to control scour worms in weaner sheep

Note that ‘Smart grazing’ principles were developed for sheep and have not been fully evaluated for goats.

*where ‘goats’ are referred to, include sheep and alpacas, as they can carry goat worms. While cattle also carry some goat worms, adult cattle tend to have very low burdens and contribute very little to contamination of pastures with worms affecting goats.

Choosing kidding paddocks

Kidding paddocks should firstly be chosen with suitable feed, shelter and predator control in mind. Then choose the least contaminated kidding paddocks for the most susceptible kidding does (maidens, oldest does and multiple kidding does).

Choosing weaning paddocks

Select weaning paddocks with lower worm risk—these could be hay paddocks, new pastures, stubbles or paddocks grazed by mature cattle.