For the 2014 analysis GrassGro™ was used to calculate the financial performance of each bloodline.
GrassGro™ is a decision support tool that uses historical weather data to drive models of pasture growth and animal production, with changes in the water content of the soil, pasture growth and decay and responses to grazing.
The greasy fleece weight, yield, fibre diameter and liveweight for each of the 71 bloodlines provided the livestock production parameters.
Enterprise structure, prices and costs were held constant and were reflective of a wether enterprise, with wethers shorn three times and then sold. The simulations ran from 1960 to the end of 2013, which accounted for the full range of seasonal conditions from drought through to long wet years.
Median wool and mutton prices for the 5 years from 2009 to the end of 2013 were used, as well as high (typical of 2011) and low (typical of 2013) wool prices (see table below).
The stocking rate (wethers/ha) was chosen such that the bloodline with the median liveweight would achieve the rule of maintaining not less than 60% ground cover for any day in 71% of the years.
The GrassGro™ simulations used typical soil, pasture and weather conditions for three sites, representing three different environmental systems with typical pastures for each location:
Two measures of financial performance are provided: