For sales and advice call
1300 327 626

The Farm Co

Same Day

The Farm Co


The Farm Co

Depots in
Each State

The Farm Co


The Farm Co


The Farm Co


Small Farm Supplier & Experts


Blog Categories

$10 off
your first order

Join now for instant savings!

need Help?
1300 327 626

The Farm Co
Home >  Blog >  Why parasite control should be your number one sheep priority.

Why parasite control should be your number one sheep priority.

Posted by Amanda Walker on 13 October 2016
Why parasite control should be your number one sheep priority.

When you have farm animals, unfortunately worms, lice and flies are sure to follow. Infestations can make members of your flock unwell and even cost them their lives. Regular monitoring of your animals will ensure early detection and the subsequent effective management of common pests.

1. Flystrike

  • Flystrike is the insect pest condition that everyone associates with sheep. It is a painful condition that, if not treated promptly, can result in death.

  • Flystrike is caused by blowflies which are attracted to smelly, warm, moist environments such as faeces build ups (dags); sweaty, moist skin folds; or open wounds.

  • Animals will often become flystruck around their anus, although this is not the only region prone to flystrike. Rams can become flystruck in between their horns or on their pizzle.

  • Flies are more abundant during humid times of the year.

  • Flystrike is caused when adult blowflies lay eggs on the skin of the sheep, which hatch into maggots.

  • The maggots feed on the sheep's flesh while they grow ('s gross...) before they drop to the ground and pupate, to hatch eventually into adult flies and begin the process again.

While the maggots are living on the sheep, it develops from being extremely irritating to painful, and sheep can die through shock or infection if the condition is allowed to persist for a number of days.

Once sheep are infested you will need to shear the affected area and expose the maggots. You will then need to treat with one, or more, chemical application(s) to kill the maggots, and disinfect the wounds.

Without a doubt, flystrike is the most horrific condition that sheep can succumb to. Prevention is far kinder than cure and needs to be part of your normal management routine. All sheep need to be observed at least every two days and affected sheep should be treated immediately.


2. Wiggly Worms

There are two major types of worms that affect sheep in Western Australia (WA); barber's pole and scour worms.
  • The adult worm lays eggs in the digestive system of the sheep.

  • The eggs pass out of the sheep and hatch as larvae in the pasture, where they are ingested by the sheep through grazing, become adult worms, and the cycle begins again.

  • Worms can cause damage to the lining of the gut, poor appetite, diarrhoea (scour worms), or weakness and death due to blood depletion (barber's pole worm).

  • By the time a sheep is visibly affected, the infestation is severe.

  • The main signs of barber's pole worm are weakness and anaemia (pale membranes of the mouth and eyes).

  • Scour worms will result in weight loss, weakness and diarrhoea (scouring).

Carrying out a regular worm egg count (WEC) by submitting faecal samples to a veterinarian is the best way to keep a handle on worm burdens.

Drenching should only be carried out when necessary, as worms can become resistant to the drench if it is used indiscriminately, making control more difficult.

When you see visible signs of worm infestation, such as diarrhoea, investigate the cause immediately. Once an accurate diagnosis is made, treatment of affected animals to prevent the problem getting worse is strongly recommended. You should also seek advice in relation to a whole of flock preventative worming program.


3. Itchy and scratchy

The third parasite you need to check for is lice. A heavy infestation of sheep lice can cause severe irritation. This can lead to the affected animal becoming distressed, suffering from a loss of appetite and subsequently losing weight and condition.

  • Lice are a common parasite in sheep flocks, and some animals are more resilient than others to a heavy infestation. 

  • Sheep lice spread easily from sheep to sheep through direct contact. The presence of one infested sheep indicates a potential infestation throughout the flock. 

  • Infested sheep should be treated with an appropriate product ideally after shearing.

On occasion, sheep will need to be treated when unshorn to prevent significant wool damage.

If individual animals are found to be suffering from a heavy lice infestation, and rubbing to the point of causing wounds, they should be treated ahead of any planned routine flock treatment.

To help prevent lice infestations, quarantine any sheep that you acquire from outside your property until you can be sure they are lice free. Build and maintain sheep-proof fences to keep out infested strays.

Sheep welfare tips

  • Sheep need to be monitored at least once every two days by someone who can spot the signs of a pest infestation.

  • All new animals to the property need to be held in a quarantine area before being introduced to other stock.

  • Your vet is a good source of information and you may find that local farmer groups or breed groups can also offer support.

  • Animal welfare is your responsibility. By failing to treat your animal, you could be guilty under the law if 'reasonable steps' in terms of prevention and treatment are not undertaken.

Sheep can be a marvellous addition to your small property, you just need to be prepared for the challenges that come with. As always, your local Ag department will have a wealth of information and resources to help. In WA, more information can be found at

Happy farming!


Amanda WalkerAuthor: Amanda Walker
About: Amanda Walker is the Director of The Farm Co and Yerecoin Traders. Amanda has extensive experience in animal health, working for a number of years with the Institute for Animal Health in the UK. Amanda also worked for a UK government response team during the Foot and Mouth outbreak back in in 2001. Amanda has a keen interest in sheep and livestock health, working with her local grower to help manage their parasite control throughout the seasons.
Connect via: Twitter
Tags: The FARM Co Animal Health Flystrike Flystrike prevention Lice management Sheep Sheep Lice Small Farm Management

For sales and advice Call 1300 327 626

Follow Us On