Íslenskar landbúnaðarrannsóknir - 01.03.1970, Page 15

COLOUR IXHERITANCE IN ICELANDIC SHEEP 13
birth is a very liglu grey colour, where
only a minor proportion o£ the outer coat
fibres are black, the others being either
wliite or tan. These lambs could some-
times mistakenly be classified as showing
the birthcoat pattern of some of the dark-
faced breeds, where the birthcoat fibres are
black at the tip, giving the body a grey
appearance. These darkfaced colours are,
liowever, so rare in the Icelandic slieep
that confusion has been avoided.
In the present study, the definition
given above for grey colour has been strict-
ly adhered to when the colours were classi-
íied. It became evident during the course
of collection of the present data that as
knowledge about the criteria for grey
colour increased and by increased experi-
ence, doubtful cases were very rarely en-
countered.
For differentiation between the different
amount of black fibres in the birthcoat of
grey lambs, a scoring system was adapted
and used on some of the farms, where the
data for the present study were collected.
The scores ran from 1 to 7, and the
characteristics of the type of grey witliin
each score is given below.
Score Shade of grey colour at birth
1 Lightgrey or lightgrey-speckled on
liead, feet and body.
2 Lightgrey and tan on body, lightgrey
or grey and tan on head and feet.
3 Lightgrey on body, darkgrey on liead
and feet.
4 Lightgrey spots in medium to dark-
grey colour on body, darkgrey colour
on head and feet.
5 Medium to darkgrey on head, feet
and body.
6 Medium to darkgrey on body, dark-
grey on head and feet.
7 Darkgrey on body, head and feet.
Colonr 03 — black badgerface (Plates II, 4;
II, 5; III, 6; IV, 1 and IV, 6)
The badgerface pattern is highly sum-
metrical.
The belly of the animal is black, both
undercoat and outercoat, the black colour
extending backwards to the inner side of
the hindlegs, up around the anus and to
the underside of the tail. The black colour
extends forward along the brisket to the
inner side of the forelegs, up along the
underside of tlie neck in a narrow line,
covering the underside of the lower jaw.
The inside of the ears is black. Sometimes
black badgerface animals have a black
patch with illdefined outlines in both rear
flanks, the reverse of the light saddle of
the wild Mouflon.
The lieadmarkings, wliich were used as
the main criterion for this colour when it
first was described (Roberts, 1924, Wriedt,
1924), are not so clearcut in the Icelandic
sheep that they can be regarded as a per-
manent feature of the character.
The bars between the eyes, which were
regarded as the main features of the badger-
face pattern when it first was described,
are visible in the lighter types of badger-
face in the Icelandic sheep, but not in the
darker types. They cannot therefore be
used as criteria for the pattern in Icelandic
sheep. The same applies to the Old Nor-
wegian sheep (Berge, 19G4 a). One feature
of the head pattern seems, however, to be
present in all black badgerface animals,
and that is a light-coloured spot under-
neath the eyes.
The parts of the body which are not
black, have a dirty wliite or tan colourecl
outercoat, while the undercoat fibres are
often black, giving a grey-coloured band at
the base of the staple, as the undercoat
grows. 'I'liis giey colour is .the reverse of
the ordinary grey, described above. This