Because of the extreme fineness of the fiber produced, a mature, top quality doe might produce only 250 grams of down (about 1/2 a pound) a year. A large buck or wether can produce 350 grams of down. The goats that produce more than this should be investigated to the fullest extent. It is more than likely that these “high producing” animals are not really producing cashmere but a closely related yet lesser quality fiber that is just not up to snuff.
Fiber diameter is a function of both genetic make-up (genotype) and environment. The characteristics that an animal exhibits is called its “phenotype”. Phenotype is a product of both genetics and environment. In order for an animal to express its true genotype, environmental pressures must be minimized. In other words, there should be no stress placed upon the animal that might make it grow finer fiber. All other things being equal, thinner animals will have finer fiber than well fed ones. Early research into the effect of diet upon fiber diameter indicated that the more an animal was fed, the coarser its fiber became. Later studies failed to support these early findings. Although this is just a theory, it is possible that the animals used in these early tests were not sufficiently selected for genotype, resulting in misleading conclusions. If you feed a goat that is genotypically predisposed to have fine fiber, it will get bigger physically, but it will not get significantly coarser. If you feed a goat that is not predisposed to fine fiber, it will coarsen and be culled on fiber.
Even at this late juncture in the history of the cashmere industry, we are still searching for goats that are genotypically fine. This is the reason that there is not now a registry or any such thing as a “registered” or “purebred” cashmere goat. Anyone who might lead you to believe that there is such a thing should be discounted as a fraud. Generally speaking, goats grown on range conditions in Texas or other arid regions will have finer fiber than they might be genetically disposed to have. And it is just a theory that goats raised at higher latitudes have more production than those raised nearer the equator. Five years or more of scientific investigation will be necessary to prove or disprove this theory. Early results suggest that latitude plays no role in determining fiber production levels. Also, cold climates do not mean that goats will grow finer fiber or more fiber. Fat goats will exhibit their genotype no matter where they are raised, hot or cold.