The nutritional control of the growth and properties of mohair and wool fibers: a comparative review.

The effect of nutrient status on the growth and properties of wool and mohair fibers is reviewed: the aim is to compare effects on sheep and Angora goats and emphasize differences between the species. Wool growth is markedly influenced by nutrition; the requirement for energy-yielding nutrients is low and the major nutrients limiting wool growth are essential AA, sulfur-containing AA being especially important. An adequate supply of Cu, Zn, folic acid, and pyridoxine is required to maintain wool growth. Both length growth (L) and diameter (D) of wool fibers respond to changes in nutrient supply such that the ratio of L:D remains approximately constant. Mohair production is influenced by nutrient supply. However, the importance of specific nutrients has not been established, apart from one study showing that mohair growth responded to parenteral supplementation with methionine. In contrast to sheep, some studies indicate that length growth of mohair fibers may not be very responsive to changes in nutrient status. The responsiveness of mohair growth (both length and diameter) to nutrient supply at different times of the year has not been reported. The energy requirement for fiber growth may be greater in goats than in sheep, but more studies are needed.