As part of the CSIRO Fine Wool Project, analyses of wool sale data have been carried out to estimate the real value of differences in the style of a sale lot of wool. This information is important to enable breeders to place appropriate emphasis on this trait in their breeding programs.
We have examined the entire sale lot data from three wool statistical areas over four years (1991–1994). The wool statistical areas were chosen to be examples of fine and superfine wool growing regions, and they were:
From the available sale lots designated as originating from these three areas, we then chose only those lots that satisfied the following conditions:
These prerequisites resulted in a data set for the analysis as indicated in Table 1.
As can be seen from the Table the wools averaged close to Best Topmaking types. Also noticeable is the extreme volatility in price across years.
The statistical analysis we conducted to isolate the effect of differences in style took account of all the identifiable influences on price. By including these factors that influence price in one large equation, we can end up with an estimate of the effect of style grade on price free from the biasing effect of all other factors.
In general, the results show the following:
These results are currently being extended to include other fine wool growing areas, and to also include more recent years.
These results are highly significant for fine and superfine wool growers. Rewards are certainly there for production of high quality fleeces.
From a ram breeding perspective the results are also important. The relative importance of style premiums in the context of a breeding program will depend on how variable the trait is in a breeding flock, how heritable is the trait, and the relationships with other traits of economic importance which are used as selection criteria.
Work is continuing in the CSIRO Fine Wool Project to formally incorporate style and the other additionally measured traits, such as length and strength, into index equations that can be customised for individual breeders.
In this issue of The Wool Press: