Making sense of the Alpaca Fibre Analysis.
Getting a fleece test is a great way of determining the quality of your alpacas fleece. A side sample is taken at shearing time and placed in a plastic bag and labeled with the alpacas name and IAR number. It is a good idea to send the samples you are getting done in one batch as you can get a 'mob average report' which details the individual results as well as the mob as a whole.
SD, CE, CF, SF, and micron are terms used in the analysis of the fleece and are used to determine and compare the quality of the fleece, but what are good results? Below is a brief explanation of these commonly used terms and how to determine a good result.
The micron is the overall average fibre diameter of the fleece sample, diameter being the straight line distance from one side of the fibre to the other. The micron is the most commonly used term in describing the quality of an alpaca fleece, but it should not be taken into account by itself. It must be remembered that the micron is the 'average' and therefore could have a large or small range (minimum to the maximum diameters).
The SD, standard deviation, is a measure of 1 standard deviation either side of the micron average where according to the 'empirical rule', 67% of the fibre diameters lie. The empirical rule also estimates that 95% of the fibres lie within 2 standard deviations of the average. For example, if the micron average was 20 micron, and the standard deviation is 4, this means that approximately 67% of the fibres will be between 16 and 24 micron. 2 standard deviations approximates to 95% of the fibres lie between 12 and 28 micron. Therefore, a lower SD is better.
The histogram below left has a micron of 16.4 and an SD of 3.6, hence the small spread or width of the graph. The histogram on the right has a micron of 21.4 and an SD of 5.2, hence the wide spread.
The CE, coarse edge, is the percentage of fibres that are 10 microns over the average micron. For example, if your average micron is 18 micron and the CE is 5.0%, then 5.0% of fibres are over 28 micron. Any CE under 3% is considered satisfactory.
The CF, comfort factor, is the percentage of fibres less than 30 micron. It is quite common to have a CF of 100% but high 90's would be considered a good result. The histogram above left has a CF of 100%.
A fibre analysis can be useful in determining the quality of an alpacas fleece when deciding to purchase an alpaca or for stud services, but should not be solely used in the selection process. Other aspects to consider are body condition, alpaca size, and the overall health of the alpaca.
If you are wanting fleece analysis, below are
a few contacts:
Micron Man
P.O. Box 1423
Bibra Lake
WA 6965
Ph. (08) 9418 1733
Southern Tablelands Fibre Testing
Thalaba Downs, Laggan
NSW 2583
Ph. (02) 4837 3210
Alpaca Maintenance - More information on alpacas
Putting weight on thin alpacas
Fencing for alpacas
How to determine signs of a sick alpaca
Basic first aid kit for alpacas
Alpaca body temperatures
Can cold and wet weather affect alpacas?
Making sense of the alpaca fibre analysis
Rye grass staggers
Taking the perfect alpaca photograph
Facial abscess
Berserk male syndrome
Vitamin D
Weaning
Constipated crias
Preparation for Winter
Keeping alpaca records
Alpacas need head-space
Testing for parasites
Birthing help
Cutting Toenails
A Working Dog's Guide to Alpacas
Paddock Maintenance
Alpacas for Pets
Alpacas as Sheep Guardians