1 The Angora goat has been selected almost exclusively for fiber (mohair) production, and as such can be considered one of the outstanding success stories in animal breeding. Many Angora goats produce up to 20-250f their body weight annually in fiber. In terms of growth rate of mohair fiber, they produce approximately double the rate of most types of sheep. Expressed as a function of body weight or feed intake, their rate of fiber production is about four times that of most sheep. However, since a high proportion of their nutrient intake is expended for fiber production, Angora goats are relatively poor meat or milk producers. Of course, slaughter of cull breeding stock provides some meat. It may be possible to develop dual-purpose meat and fiber producers, but only under conditions of better nutrition than that where most are run at the present time. Thus, for this discussion it is assumed that Angoras are bred primarily for fiber. The possibility is recognized that Angoras are kept for their usefulness in clearing brush and weeds on the farm or ranch also and that some are simply pets.
2 In selecting for fiber, one is interested in both quantity (weight) and quality of fiber (length, fineness, style, character, absence of kemp, etc). In addition to fiber, one must be concerned with traits that contribute to the survival or viability (soundness, fertility, etc.) of the individual and flocks.
3 Selection for quantity of fiber is accomplished efficiently by using fleece weights of those Angoras (mostly young males or young females) which are being considered for use as breeding animals. However, history indicates that most producers practice visual selection. In this case the predicting indicators of fleece weight are: size of the animal, completeness of cover, length of fiber, diameter of fiber and differences in density. The amount of grease (oil) or dirt in the fleece contributes to overall fleece weight, but not to fiber weight. It is preferable to emphasize fiber weight over total fleece weight. Environmentally (i.e. phenotypically), the two tend to be positively correlated, but genetically they are negatively related since the oil production requires a substantial amount of feed-energy. Similarly, one should not overemphasize the size of Angoras as a means of obtaining fleece weight.
4 Phenotypically, size and fleece weight are
positively related but genetically they tend to be negatively correlated. For assessing efficiency of production, the genetic correlation is the more accurate term since it is not possible to produce meat and fiber from the same units of feed-energy. Fiber diameter is phenotypically and genetically positively related to fleece weight, but negatively to fleece quality since the finer fiber is more desirable. Completeness of cover includes mostly head, neck, belly and legs. They are genetically related to fiber production. Face cover, however, can interfer with vision and have serious effects on the animal's welfare. This is even more true with range goats where reduced vision can interfer with their ability to graze selectively. The amount of mohair cover on the face contributes little to total fleece weight, but is genetically linked to total cover at other points. The amounts of fiber on neck and belly make important contributions to fleece weight, but the value of fiber grown on the legs (below the knee or hock) is rather low. Therefore, selection for body cover should be limited to the neck and belly, primarily the former. Animals with extensive cover in the face should be eliminated.
5 Selection for mohair quality includes primarily fiber diameter (finer fibers preferred), length (four inches minimum), freedom from kemp (coarse, brittle, chalky white hair mixed in the fleece), and desirable lock formation. There is little technological support for selecting for a specific lock type or formation, but in the absence of detailed studies it seems undesirable to allow the fleece to become straight or without some more appealing lock character.
6 Limited research indicates that all the desirable economic traits of Angora goats are moderately to highly heritable and can thus be changed through selection. Some strong negative relationships exist. Also, problems may be encountered due to genetic, environmental interactions. For example, selection for high level of fiber production tends to make the animal poorly adaptable to the range conditions under which most are produced presently.
7 Age of selection deserves some discussion. Weaning or first shearing is a poor time to select Angora goats. The second and third shearing (one year and 18 months) provide a much better age to appraise the fiber production potential. Angora goats tend to have high longevity. Thus, culling of Angoras with advancing age can be based on fiber production and less on teeth wear as practiced with sheep. Fleece weights tend to deteriorate (quantitatively and qualitatively) with advancing age. Removing Angoras with deteriorating fleece production can improve directly the evaluation of fleece traits and long-term selection.