The effects of sheep breed on the defects pinhole and raised rib
S. M. COOPER
New Zealand Leather and Shoe Research Association, Private Bag
11 333, Palmerston North, New Zealand.
E-Mail:
NZSAP 2002 Abstract No. 19
Proceedings of the New Zealand Society of Animal Production 62:
69-71
The effect of sheep breed and wool type on the incidence of the
skin defects "pinhole" and "raised rib" was investigated. Six
breeds/crosses were used - pure Romneys and Suffolk x Romney, Dorset x
Romney, East Friesian x Romney, Texel x Romney and Merino x Romney
crosses. Skins were recovered at slaughter and processed to dyed crust
leather, then scored numerically for the severity and extent of pinhole
and graded into the "Run" (best quality), "Pinhole", and "Thirds"
grades. The presence or absence of raised rib on the skins was noted.
Wool bulk and fibre diameter were measured. Skins from Romneys had the
least pinhole and Merino crosses the most. Skins from Texel, Dorset and
East Friesian crosses were also significantly more likely to be
downgraded due to pinhole than those from Romneys. Within-breed
differences in the level of pinhole were due to wool bulk differences,
with a higher wool bulk correlated with more pinhole. Merino-cross skins
were much more likely than the skins from pure-bred Romneys or the other
crosses to have raised rib. Texel-Romney-cross skins were more likely
than pure-bred Romney skins to have raised rib. There was no difference
between the mean wool fibre diameter for ribby and non-ribby skins, but
the ribby skins had a significantly higher wool bulk.
Keywords: NZSAPAB;
sheep; breed; pinhole; rib; skin; leather
Last Updated 30/07/2002
