Scientific Basis to SRS®
SRS® breeding of alpacas involves the direct selection for low primary fibre diameter and for high levels of fibre density and fibre length.
This approach is adopted mainly because the genetic regulation of fibre diameter is known to differ between primary follicles and secondary follicles.
Primary fibres are produced by the first-formed follicles in the unborn alpaca's skin at about day 214. The secondary fibres, which outnumber primary fibres by about 10 to 1, develop later from about day 343.
The fact that alpacas worldwide still have primary fibres that are on average, 10 microns coarser than the secondary fibres, is a sign that effective breeding strategies to reduce guard hair are not yet in place.
The mean diameters of the primary fibres and secondary fibres need to reduced to less than 17 microns in order to remove all guard hair and fibre medullation.
Another compelling reason for adopting the SRS® breeding approach arises from research work indicating that fibre density, fibre length and fibre fineness are likely to be regulated genetically by the number, distribution pattern and activity of pre-papilla cells in the foetal skin.
The working hypothesis for maximising fibre density and length is:
- pre-papilla cells regulate wool follicle formation and fibre size
- a large starting population of pre-papilla cells need to be available in the foetal skin to create the potential for a large number of wool follicles to be formed
- pre-papilla cells need to be distributed as small clusters to form a high density of wool follicles
- because all the clusters are small, the fibres, whether originating from primary follicles or secondary follicles, will be fine in diameter and non-medullated
- these small clusters need to emit strong signals from the base of the wool follicles to stimulate the growth of long fibres
Laboratory tests show that the density of different alpacas vary from 20 to 90 follicles per square millimetre of skin and the fibre length from 0.20 to 0.60 millimetres per day. Doubling the density and length of fibres on an alpaca would change it from producing a fleece of 3 kilograms of 25microns to the equivalents of 7.5 kilograms of 20 microns or 4.2 kilograms of 15 microns.
So, how do we breed an advanced alpaca producing high fleece weight of fine diameter wool of exquisite quality?
Several things need to happen simultaneously.
- the mean primary fibre diameter needs to reduced to less than 17 microns in order to remove all guard hair and fibre medullation
- the density and length of the fibres need to be increased
LATEST NEWS UPDATES
Merry Christmas and a happy 2012
Date Article Listed: 24/12/11
As the year draws to a close we would like to wish everyone a very merry Christmas and a happy, healthy and successful 2012. Although there are plenty of challenges ahead the baling weekend indicated that really positive gains are been made in the fleece area.
Thank you to everyone who attended workshops, assisted with displays, helped with baling and who contributed to the success of the year. May this time be a time for family and friends and a time to relax. Have a safe and happy break.
Fleece Baling Weekend
Date Article Listed: 24/11/11
Over the last weekend 19th & 20th of November a number of us met at Frank and Julienne Gelber's property at Orange to class and bale fleeces for the Primaries wool auction in December. Although it took a long time for those present it was an excellent learning experience and one all subscribers should try and be part of in the future. Some of the fleeces were very well prepared while others required further skirting. Thanks to those subscribers who contributed to the collection. In total over 700kgs of fleeces was classed and a number of bales of 110kgs were pressed and branded ready for sale. Some are still waiting to have enough fleece to make the necessary weight.
Many thanks to the Gelbers for their hospitality, to Jim Watts who classed every fleece and to Stuart Marshall, Richard Brennan, Julienne Gelber and David Mitchell for sorting , skirting, pressing and branding the bales. Go to the photo gallery for some pics of the days. By the time we finished all were exhausted but more informed by the experience. We wait to hear how the fleeces test and how they sell on the open wool market.
BULLETIN BOARD
New subscribers welcome. For more details click on:
