Making More from Sheep Australian Wool Innovation Limited Meat & Livestock Australia
MODULE 11: Healthy and Contented Sheep
Tool 11.16
Previous Index Next

Footrot

Control

When conditions are green and pasture is growing, controlling the expression of footrot is the best option. The objective is to limit production losses and reduce the number of sheep with footrot. Control is best achieved with either foot-bathing, vaccination, or a combination of both, depending on labour resources and the severity of the strain of footrot. Control continues while conditions are green. Benign strains may not need control except for occasional foot-bathing in wet years.

Eradication

If virulent footrot is diagnosed on your property, eradication is an important priority. The first objective is to eliminate potential sources of re-infection. It is not worth trying to eradicate benign footrot. Two broad options exist for eradication: total destocking and replacement with footrot-free sheep or inspection and culling of all sheep with abnormal feet when conditions are dry. If high numbers are infected, initial salvage of infected sheep may be warranted. After a few inspections during the non-spread period, mobs should be quarantined and, once all sheep have spent a spring with no evidence of footrot, you can be confident that footrot has been eradicated. Always seek advice on footrot diagnosis and management from an experienced animal health adviser.

Ovine Johne's disease (OJD)

Control

If OJD has been diagnosed on your property, management options are available to limit the impact of the disease. The main option available is to use Gudair® vaccine to help control the disease in your flock. Initially, if the prevalence of clinical disease is high, identify and remove sheep showing signs of wasting to help reduce death rates. Minimise stress due to worms and poor nutrition. The other important issue is to minimise the risk of spreading OJD to other flocks. Ensuring boundary fences are 100% stockproof is important to limit the spread. In addition, run low-risk sheep in boundary paddocks. Seek advice from your veterinarian or state government veterinarian. Information is also available from AWI: www.wool.com, MLA: www.mla.com.au and Animal Health Australia www.animalhealthaustralia.com.au.

Lice

Control

If lice are detected in your sheep during the year, control of fleece damage by jetting may be necessary before shearing. If there is at least six months to go before the next shearing and there are signs of wool damage or lice have been found, then long wool treatment is probably necessary to avoid excessive wool damage. If there is less than 2 months to go before shearing, the long wool treatment will probably not be economic unless wool damage is already severe. Between these times the need for treatment depends on the severity of wool damage (see the LiceBoss long wool tool at In cases where wool rubbing is seen, but no lice can be found, the lice detection test can be used to check whether lice are present. For more information see: http://www.liceboss.com.au/.).Several chemicals are available for lice control. The choice depends on the time before shearing as withholding periods must be observed. Effective control will only be achieved if you follow recommended dose rates and application techniques. Remember that eradication is not possible in sheep with long wool, so long wool treatment is only to control lice and reduce further wool damage until shearing. The most effective control will be achieved by using correct jetting technique. Guidelines for managing sheep lice can be found in the Lice Sense download on the AWI website www.wool.com.

Eradication

Eradication of lice will only be achieved if all sheep are treated after shearing at the same time, correct dose rates used, and either a backline or plunge dip correctly applied. If ewes are treated within 8 weeks before lambing using any backline treatment or dipped with an insect growth regulator (IGR) then the lice may not be eradicated before the lambs are born. Lambs may become infested and then reinfest the ewes. Dipping heavily pregnant ewes poses animal welfare risks, so avoid shearing within 8 weeks before lambing if lice treatment may be necessary. Seek advice about application technique and eradication from an experienced veterinarian or animal health officer.

If no lice infested sheep are introduced and boundary fences are 100% stock proof, you will not have to re-treat sheep once lice have been eradicated. This will be a major cost saving, as well as reducing residues in the wool clip.