Improvement of wool production and quality by the use of sheep rugs on Gansu Alpine Fine wool sheep in north-west China

Abstract

SUMMARYFine wool in China is characterized by severe dust contamination and substantial tip weathering. In an attempt to improve wool quality, synthetic rugs were fitted to ewes and a range of raw wool characteristics was monitored. Two trials were carried out in successive years: a pilot trial (June 1985 to June 1986) involving 100 ewes wearing rugs and 75 controls, and a main trial (June 1986 to June 1987) involving 250 ewes with rugs and 250 controls. The rugs were fitted to ewes after shearing and remained on until shearing the following year. Wool from ewes with rugs was significantly better in almost all the characteristics measured (P <0·05) than wool from sheep without rugs. Clean fleece weight was improved by 15% over the two trials, yield and wax content were increased, and dust content and dust penetration were substantially reduced. Staple length and strength were increased, and dust content and dust penetration were substantially reduced in the main trial. Several style characteristics were measured using a prototype image analysis system and these also showed wool from sheep wearing rugs as being of better quality than wool from sheep in the control group. The only negative result was an increase in yellowness, in the greasy state only, due to the higher wax content in the sheep wearing rugs and the yellow nature of the wax of Gansu Alpine Finewool sheep – probably due to their genetic background. Wool from sheep wearing rugs would be expected to perform better in processing than wool from unrugged sheep.