Can an exceptional alpaca herd sire reliably transmit his strongest qualities to future generations? The latest Genetic Focus test results suggest that Van Dijk belongs to this select group of males.
Understanding SD Across
Developed by Art of Fibre, SD Across testing allows breeders to assess the genetically influenced uniformity of fibre. Unlike the traditional SD (Standard Deviation) value, which includes both variation between fibres and variation along the length of the fibre caused by environmental factors, SD Across focuses primarily on differences in diameter between individual fibres. As a result, it provides a clearer indication of the genetic component of fibre uniformity.
The lower the SD Across value, the more uniform the fleece. More uniform fibre means individual fibres are closer in diameter to one another, creating a more consistent fleece. Because this trait is highly heritable, SD Across can be a valuable tool for evaluating breeding stock and identifying animals with the potential to pass superior fibre uniformity on to future generations.
Van Dijk – An Outstanding SD Across Result
Van Dijk achieved an SD Across value of 3.84 µ. For comparison, the average result for mature alpacas in his age group is approximately 5.5 µ, while the threshold for the top 10% of the population is 4.2 µ.
This result alone places Van Dijk among the elite animals tested. However, the true value of a breeding male becomes evident when similar results begin to appear in his offspring.
Momper of Van Dijk, Mancadan of Van Dijk and Penrose of Van Dijk
The most exciting aspect of Van Dijk’s Genetic Focus results is what we are now seeing in his progeny.
Momper of Van Dijk achieved an SD Across value of 3.08 µ, while Mancadan of Van Dijk recorded an impressive 3.28 µ. These are exceptionally rare values that clearly exceed the threshold for the top 10% of young alpacas.
Penrose of Van Dijk also demonstrates the strength of this breeding line, recording an SD Across value of 4.20 µ, placing her within an elite group of animals.
Results such as these are unlikely to be a coincidence. When multiple offspring from the same sire consistently achieve outstanding scores for the same trait, we begin to see evidence of repeatable genetic transmission—one of the primary goals of modern alpaca breeding.
Why Is SD Across Important?
Fibre uniformity is important not only for breeders but also for fibre processors. More uniform fibre generally results in improved processing performance, higher-quality finished products, and greater predictability in breeding outcomes.
For these reasons, SD Across is increasingly being recognised as one of the most valuable measurements available for evaluating the genetic merit of alpacas.
Van Dijk – A Herd Sire Proven Through His Progeny
Van Dijk’s show successes, exceptional fleece structure, and outstanding fibre uniformity have been evident for many years. Today, these achievements are being reinforced by the results of his offspring.
Momper of Van Dijk, Mancadan of Van Dijk, and Penrose of Van Dijk demonstrate that Van Dijk is not simply a male with an exceptional fleece of his own. Increasingly, the evidence suggests that he is a herd sire capable of consistently transmitting superior fibre traits to the next generation.
And ultimately, that is what distinguishes a good alpaca from one that can genuinely influence the future direction of a breeding programme.
