This tool is a model to assist sheep producers decide the appropriate number of ewes to allocate to self-replacing Merino joining and a first cross joining, with the aim of maintaining a sustainable, self-replacing flock.

After entering flock structure data (number of age classes, weaning percentages, etc) and a figure for the proportion of ewes to be joined to terminal sires, choose the ‘calculate’ button and the service will indicate whether there will be a deficit or surplus of hogget ewes to maintain numbers in the self-replacing Merino flock.

Alternatively, a manager can indicate the production figures and then check the ‘break even’ checkbox and click ‘calculate’ to find out the number of ewes to allocate to each flock to break even, that is finding the maximum number of ewes to be joined to terminal sires, while just maintaining the self-replacing Merino flock.

This tool may be run on-line or downloaded and saved to your computer as a Microsoft Excel file.