WOOL GRADING AND PROCESSING SYSTEM TO IMPROVE THE UTILITY OF THE EGYPTIAN BARKI WOOL

Abstract

SUMMARY The present study aimed to define those wool traits of significant processing performance to be included in the sheep breeding program. About 1.64 tons of wool was harvested from the flock of Barki sheep at Maryout Research Station belonging to the Desert Research Center. The harvested wool was subjected to a clip preparation technique and subjectively graded for harshness and bulkiness into four lines; L1: coarse wool with high bulk, L2: coarse wool with low bulk, L3: fine wool with high bulk and L4: fine wool with low bulk in addition to another one (L5) as a wool line left without grading for comparison. Representative wool samples were taken from each line to measure fibre diameter (FD), standard deviation of FD (SDfd), medullated fibre percentage (M%), prickle factor (PF%), loose wool bulk (BUL), resilience (RES), staple strength (SS), point of break (POB) and staple elongation (EL) in order to determine the characteristics of each line of the raw wool. The formed wool lines were sent to the manufacture to be processed according to the normal procedures practiced in such mill. Representative wool samples were also taken from each line after carding, after spinning and from the processed blankets. These samples were tested according to the Egyptian Standards for blankets. The same wool traits measured in the raw wool were tested again from those samples taken from each line after carding. Samples collected to represent each processed line after spinning were used to measure yarn count, yarn strength and elongation, coefficient of variability of irregularity of yarn mass and yarn hairiness. Some blanket properties such as weight of blanket/ m 2 , heat loss, air permeability, strength and elongation as well as covering factor were also recorded from samples taken from each line of processed blanket. Results indicated that L1 and L2 had significantly higher FD, SDfd, M% and PF% as well as less SS and EL compared with L3 and L4. L1 and L3 had significantly higher BUL and RES compared with L2 and L4. Blanket weight/ cm 2 was significantly lighter for blankets processed from those lines of more harshness (L1 and L2) and more bulkiness (L1 and L3). Moreover, blankets made from higher BUL wool lines tended to maintain more heat and being less permeable with significantly better covering, while blankets made from finer wool lines tend to be stronger and more extensible. The present study recommend that blanket made from L1 line to be the best since it provides better processing efficiency in terms of yarn count as well as producing blanket with the least blanket weight/ cm 2 and maintaining more heat. Moreover, the manufacturer could save about 20% of the