On-farm fleece testing

On-farm fleece testing has started to become increasingly popular since 1999. On-farm testing may give some growers more flexibility in the way they manage their flocks. Fact sheets on the profitability of fleece testing, published by the Sheep CRC and Agriculture NSW in Australia, can be found here. Since 2000, Australian Wool Innovation (AWI) and the Sheep CRC in Australia have invested heavily in R & D which has shown the ongoing financial benefits of individual animal measurements.  Links to their sites are shown on our Links page.

Info-bulletin 5.9 gives guidelines on the relative precision of different test methods.  Refer to page 4 for information on fleece testing methods.

There is a range of options for on-farm fleece testing. Some growers have demonstrated that using this type of service close to shearing, primarily as a tool to assist with genetic selection, gives an added advantage that data has been gathered which allows them to split lines of wool based on micron and style grades. This can be quite simply done in the race in the yards a few hours (saves a muster) or days before shearing. A side benefit to this system is that the sheep can be shorn in micron groups relieving the pressure in the shed. Greasy fleece weights gathered at shearing can usefully add to the database.

SGS Wool Testing Services is the New Zealand agent for on-farm use of the OFDA2000 instrument. The OFDA2000 instrument was developed as a fully-portable instrument, housed in a suitcase, specifically to allow diameter measurements to be made in real-time during animal selection or fleece classing see Info-bulletin 3.4. In the simplest method of use, a single staple is selected from a consistent location on each fleece or animal, and this staple is prepared and measured in its greasy form. Info-bulletin 3.7 addresses some of the issues relating to the measurement of greasy wool. The cycle of preparation and measurement takes 30 seconds or less, and throughputs of up to 1200 animals per day are commonly achieved in New Zealand by a single operator working alongside a selection team or shearing gang.

New Zealand growers have used the data from this service for both genetic selection and the objective preparation of lots for sale. Sale lots prepared in this manner are probably more uniform than lots prepared traditionally, and it remains to be seen whether buyers will pay a premium for this. Some growers have improved their wool return simply by breaking their clip into diameter-based lines. Info-bulletin 3.8 gives more detailed information on the relationship between fleece and core test diameter results. This technique will however only work when the market conditions are suitable and should not be relied upon as the principal benefit from the use of on-farm testing.

This service can also yield valuable data concerning the length-diameter profile of the wool, which is a very good indicator of the feed history of the sheep. Click here for further details on this and how such information can be used.

Wool soundness or strength has become much more important over the last few years.  With over 80% of Australian fleece wools now tested for staple length and strength, fine wool processors are demanding this information on topmaking lots. Info-bulletin 1.6 discusses the economic benefits of both the testing of sale lots and the selection of animals for staple strength.

In addition to the measurement of diameter, the OFDA2000 also measures mean fibre curvature. The results of these measurements undertaken on greasy wool staples have proven more repeatable than measurements undertaken on 2mm minicored snippets taken from laboratory-scoured samples, and this has allowed on-farm use of a prediction method for wool bulk (see Info-bulletin 5.1, and technical papers M8 and M24). Consequently OFDA2000 instruments are now being used on a more widespread basis in New Zealand for selecting animals in crossbred flocks, where bulk is a desirable property for a number of end-uses.