• The Case of the Missing Coarse Fibres: Explaining the ‘Trim High’ Setting on OFDA2000 Fibre Testing Equipment

    When I first became involved with fibre testing alpacas over 15 years ago, about the only figure on alpaca fibre test reports that received any interest was the average fibre diameter (microns). Thankfully, SD is now co-starring alongside micron, as breeders appreciate the need to reduce fibre variability when breeding towards quality fleeces. Most alpaca fibre testing these days is carried out using OFDA2000 fibre testing equipment. OFDA2000 equipment measures the full length of the fibre sample. It can measure fibre samples after the samples are ‘scoured’ or cleaned of lanolin, seeds, grass etc, or it can be used to test raw fibre samples using capabilities to offset the presence of impurities on the fibres. more »
  • Testing the Testers – Fiber Testing Alpacas

    In order to breed alpacas with better fleeces, we need to know the quality of the fleeces of our dams and sires. The only quantitative, repeatable, transferrable way to get this information is to submit samples for analysis in one of the many alpaca-fiber-testing laboratories. We are reliant on those results in assessing our animals, yet we rarely ask critical questions about those labs: how consistent and reliable are their test results? What instrument do they use for the test? What information do they provide? Where is the best value for money? more »
  • Can Selection for Skin Traits Increase the Rate Of Genetic Progress in Merino Breeding Programs?

    There is widespread interest in the use of skin properties for the selection of superior Merino genotypes. This is despite the fact that no selection experiments to date have demonstrated beneficial effects on production traits from selection based solely on skin traits. Two studies have examined whether the inclusion of skin traits in a realistic selection program improves the rate of genetic progress towards a breeding objective emphasising fleece weight and fibre diameter. Both indicated little benefit from including the skin traits. However the impact of the skin traits will depend on their heritabilities and their genetic associations with one another and with the traits in the breeding objective. There is increasing evidence that the genetic parameters differ between the Merino strains so results from one strain cannot be extrapolated to another. In this paper we examine the effects of including classer assessed skin quality and two objectively measured skin characters, skin biopsy weight and follicle density, on the genetic and economic gain made over and above that made using a standard selection index in South Australian Strongwool Merinos. The results indicate that substantial additional genetic gain can be made by including the skin traits. This was particularly true at low micron premiums where addition of all three skin traits increased the economic gain by 25%. The genetic improvement in adult clean fleece weight by including all three skin traits at this premium, was increased from 0.9% per annum to 1.4% per annum with a corresponding slight reduction in the decrease in mean fibre diameter. At higher micron premiums the benefit of including the skin traits was substantially less, again reflecting the tendency for skin trait inclusion to influence fleece weight to a larger extent than fibre diameter. Inclusion of the skin traits had little impact on coefficient of variation of fibre diameter, staple strength and staple length. Our results suggest that consideration of some skin traits may lead to moderate genetic gains and be worthwhile including in breeding programs for Strongwool Merinos, but they do not lend support to notions that consideration of skin traits will produce dramatic increases in fleece weights with concomitant large decreases in fibre diameter. more »
  • Progeny Testing of Alpacas

    The relationship between traits exhibited by any sire or dam and the traits of their progeny is indeed a fickle affair, causing untold frustration for those determined to breed their ‘ideal’ alpaca. Firstly, there is the issue of whether the desired traits of the breeding sire or dam are being influenced by genetics or by environmental factors. In the latter case, the predictability of whether the parent’s traits shall pass on to their progeny becomes (almost) purely a matter of luck. more »
  • Guidelines for Shearing and Presenting Alpaca Fleeces for the Premium Fibre Market

    The alpaca fibre market is witnessing an increase in demand for most grades of fleeces, particularly those suitable for the premium end of the textile market. In order to meet the criteria for acceptance into this market, however, fleeces need to be shorn and prepared in a manner that greatly reduces the incidence of contamination and reduces the variation of fleece types within consignment lines. more »