Íslenskar landbúnaðarrannsóknir - 01.09.1975, Síða 58
56 ÍSLENZKAR LANDBÚNAÐARRANNSÓKNIR
gested by Adalsteinsson (1970) that the
tan colour in the Icelandic sheep is the same
colour as dominant brown in the Karakul
and related breeds.
In the following, the main results ob-
tained through measurements and scoring of
wool quality characteristics with particular
reference to the occurrence and inheritance
of tan colour will be given. Some results
from investigations on the relation between
tan colour and other characteristics will be
reported on. Preliminary results from some
of the investigations described here have been
published earlier in Icelandic in farming
periodicals.
MATERIAL AND METHODS
Wool samples were collected from 140 Ice-
landic sheep in 1953 for measuring staple
length and for microscopic measurements of
fibre diameter and recording of medullation
and occurence of tan coloured fibres. The
measurements were carried out at the Wool
Laboratory of the Agricultural College of
Norway and were based on 3 samples with
100 fibres measured from each animal Adal-
steinsson, 1956).
Wool samples were collected from 204
adult rams exhibited at ram exhibition in
Iceland in the autumn of 1957 and 1959-
Measurments of staple length and fibre dia-
meter of those samples were made at the
Department of Agriculture of the University
Research Institute in Iceland (Adalsteins-
son, 1958 and 1961). In the above investi-
gations, tan fibres were also recorded and
their diameter measured.
In 1954 scoring for occurrence of tan
colour on newborn lams was initiated at the
Experimental Farm Hestur in Iceland (Páls-
SON, personal communication). The scores
used were as follows (Adalsteinsson,
1963, 1970):
Score Amount of tan colour
1 White, no tan colour visible.
2 Tan colour on head, feet or tail.
3 Tan colour on head, feet or tail, and
some tan colour on body, but body
more white than tan.
4 Tan colour on head, feet, tail and
body and body more tan than white.
5 Tan colour on head, feet and tail and
body completely tan.
Classification of individual fleeces after
shearing, based on occurrence of tan fibres,
was initiated for experimental purposes at
the Experimental Farm Hestur and at the
Agricultural School Hólar in 1961. The
classes were as follows (Adalsteinsson,
1962):
Class Amount of tan colour
A No tan fibres visible.
B Tan fibres visible in the wool from
the lower parts of the Iegs, but the
main part of the fleece free from tan
fibres.
C Tan fibres visible in most parts of
the fleece.
Classification of pelts of live lambs at
weaning at 4—5 months of age, based
mainly on amount of tan fibres present was
initiated for experimental purposes at Hestur
and Hólar in 1961. The classes were as
follows (Adalsteinsson, 1962, 1963):
Class Amount of tan colour
A White pelts, without tan fibres, outer
coat even, curly and lustrous.
B White pelts, without tan fibres, outer
coat of löwer quality than in A.
C Tan colour on outskirts of pelt, but
no tan fibres in the main part of the
pelt.
D Tan fibres clearly visible in the pelt.