This program estimates the probability that a property has lice at shearing, based on
(a) the probability that they had lice at the previous shearing and the treatment used failed to eradicate;
(b) the probability that sheep that were purchased had lice and the lice were not noticed or not eradicated if a treatment was applied;
(c) the probability that lice entered the property on strays.

These possible sources of lice are estimated and combined to give the overall probability that lice are present at the current shearing. Note that if lice have actually been seen then there is no need to use this program, just go ahead and treat them thoroughly. However, in this case the program may help to examine possible sources of infestation.

Brief Instructions for Short Wool Lice DSS

Click on the ‘Property’ tab and enter the State and region. The region sets the regional lice incidence, but if you are aware of a better estimate for you local area you can change it. Then click on the next tab sheet, labelled ‘Background’. Work through each tab in turn answering all the questions relevant to your situation.

On the ‘Background’ tab sheet. if some sheep are rubbing you should click the link ‘Check Rubbing’ before going on to other sections. If that module suggests a high probability that lice caused the rubbing then you need to treat for lice at the next shearing.

On the ‘Treatments’ tab you can get a more thorough assessment of the effectiveness of the treatment method used by clicking on the “Treatments” link to open a new page in a separate module. If you do this then write down the estimated probability of eradication from the Treatments DSS module, close that link, then enter the result back in this module. (Sorry, the two modules cannot transfer that value automatically.)

On the tabs for ‘New rams’, ‘New ewes‘ and ‘New other’ sheep, if there were no purchases in these categories then enter zero and leave the rest of that sheet blank. Similarly, on the tabs about strays if there are no neighbours in that category then leave that sheet blank.

The tabs ‘Strays no lice’, ‘Strays unknown’ and ‘Strays lousy’ check for the chance of strays coming from neighbours that are (a) believed to have no lice in their sheep, (b) are of unknown lice status, or (c) are known to often have lousy sheep, respectively. The same questions are asked on each tab because you may have different fence quality to different neighbours or you may know which category of neighbour your stray sheep came from. If there are no neighbours in any particular category then enter zero for number of neighbours and move straight to the next tab.

You can click the ‘Calculate’ button at any time and the program will estimate the probability that you have lice from the answers given so far. It is not necessary to continue to check Tabs and answer questions after it is obvious that lice are probably present in the flock and that treatment will be required.

If you want to change any data already entered, click on the required tab, make the change and click ‘Calculate’ again. Do not use ‘Back’ on your browser or you go back out of the program and have to start again.

The ‘Report’ tab sheet summarises your situation, may offer some brief comments on your risk of lice from various sources and suggest methods of reducing the risk.

If you decide to treat, use the ‘Check Products’ link for a list of registered products. This will open in a new page so you can close the ‘Products’ module when you finish and continue where you were.