A Review of the Biology Linking Fiber Diameter with Fleece Weight, Live Weight and Reproduction in Merino Sheep
By N.R. Adams and P.B. Cronjie
Are fine fibered alpacas smaller and do they cut less weight than high fleece weight, coarser animals? Do finer animals experience less micron blow out as they age? Is fineness correlated with higher follicular density in the skin and smaller animals?
Don Julio Barreda's B-Line (fine) Accoyo's are 20% finer, 20% smaller and cut 20% less fleece weight. It would seem that finer alpacas are smaller and cut less fleece.
Adams and Cronje take an in-depth look at all of these issues as they affect Merino sheep in Australia. Here are some of their conclusions.
The genes influencing the diameter of the wool fiber are unlikely to directly affect either liveweight or reproduction. Instead, effects on metabolism in finer wool sheep are likely to come about through concomitant increases in follicle density or in relative fiber length. Further effects on fleece weight or fatness may come about through selection for other characteristics associated with fine wool, such as reduced “blowout” response of fiber diameter to nutrition.
Finer wool genotypes tend to have a lower fleece weight, but this does not result in more amino acids being portioned to growth and reproduction. Rather, liveweight is also normally lower in finer wool sheep, and often the proportion of fat in the body is reduced.
Alpaca breeders can learn a lot by studying research on other fiber bearing animals.
Read the entire article. A Review of the Biology Adams.pdf
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