Íslenskar landbúnaðarrannsóknir - 01.09.1975, Page 61

OCCURRENCE AND INIIERITANCE 59
TABLE 3.
Classification of lamb pelts at weaning in relation
to score for tan colour at birth.
Birth No. of lambs in pelt class
score A-fB C D Total
1 40 64 18 122
2 57 408 210 675
3 12 65 65 142
4 2 15 38 55
5 1 2 5 8
Total 112 554 336 1002
The difference between scores for tan
colour at birth w. r. t. pelt classification is
highly significant (%28 = 117.21;P<0.001),
showing that the degree of tan colour at
weaning is to a considerable extent predic-
table from the score for tan colour at birth.
The relationship between pelt classifica-
tion of lambs at weaning and the classifi-
cation of the fleeces of the same animals at
shearing 5—6 months later together with
average wool weight by pelt and wool classes
were examined in one investigation on 90
female lambs kept for breeding at Hólar and
Reykhólar in 1963 (Adalsteinsson, 1964).
The results are shown in table 4.
TABLE 4.
Classification of wool fleeces in relation to classi-
fication of lamb pelts at weaning, and average
fleece weight by wool and pelt classes.
Pelt No. of ewe lambs in wool class Average
class A B C Total fleece wt. kg
A+B 16 6 2 24 2.05
C 0 14 14 28 2.06
D 1 2 35 38 2.06
Total 17 22 51 90
Av. fleece
wt. kg. 2.04 2.11 2.04 2.06
The connection between pelt class and
wool class is highly significant (X \ =
71.35;P<0.001) showing that the amount
of tan colour present at weaning is clearly
reflected at shearing 5—6 months later. The
fleece weight in this investigation has been
unaffected by pelt class and wool class.
Pelt classes of progeny from matings with
known pelt classes of parents were examined
in 1963 and 1964 in the experiments at
Hólar and Reykhólar (Adalsteinsson,
1965).
The numbers of progeny in each pelt class
according to mating are shown in table 5.
TABLE 3.
Distribution on pelt classes of progeny from parents
with known pelt classes.
-c
c
Number of white s >* o G G ö
Pelt progeny in pelt o <D —( <D bj) bt) o *-> o
classes class. o £ Q.H o.
of parents A+B C D Total
(A+B)xA+B) 38 24 7 69 5 74
(A+B)xC 32 48 14 94 12 106
(A+B)xD 23 81 69 173 10 183
CxC 12 32 9 53 3 56
CxD 13 36 49 98 1 99
DxD 8 28 78 114 3 117
Total 126 249 226 601 34 635
Comparison of the distribution of progeny
in table 5 with expectation under the hypo-
thesis that pelt class of progeny is unaffected
by pelt classes of parents shows a high-
ly significant deviation from expectation
(X210 = 146.99;P<0.001).
This shows that a clearcut relationship
exists between pelt classes of parents and
progeny.