Maataloustieteellinen A ikakauskirja
Vol. 60: 546—548, 1988

Performance of crossbreds of Polish Merino dams with F, rams:
Finnsheep x Polish Merino. B. Wool production of ewes

M. OSIKOWSKI, B. BORYS and M. A. OSIKOWSKI
Institute of Zootechnics, Experiment Station Koluda Wielka
88-160 Janikowo, Poland

Abstract. The investigations were carried out on wool of 180 non-selected ewes with
25 % Finnsheep (F) genotype (FxPMxPM) and 51 purebred Polish Merino (PM) ewes as
controls. The shearing took place at 23 months of age, after a year’s growth of fleece. Greasy
and clean wool production, length and diameter of fibres as well as wool character evaluated
by subjective appraisal were recorded. Crossbred ewes had a slightly lower greasy wool produc-
tion (FxPMxPM —4.0 kg, PM—4.3 kg), but a much higher rendement (60.2 and 51.2 %
resp.) and a little higher clean wool yield 2.38 versus 2.20 kg. Wool of the crossbreds was
longer (11.4 vs 10.5 cm) and coarser (24.8 vs 23.9 pm), but had a poorer character 14.9 vs
16.0 points.

Index words; Finnsheep, Polish Merino, crossbreeding, wool production, fibre length, fibre diameter, greasy wool

Introduction

Mating Polish Merino (PM) ewes to Finn-
sheep (F) rams, in addition to the main ob-
jective of improved reproduction, affects also
their wool production (1, 3). A series of trials
have been initiated on the effects of two-stage
commercial crossing of PM with F, rams:
FxPM, and on the development of a new
wool-prolific line of Merino-type sheep
through introducing a limited proportion of
F genotype to the PM. The investigations in-
clude also the analysis of wool production of
ewes with 25 % F genotype.

Materials and methods

Wool of 180 crossbred ewes (F X PM x PM)
and 51 purebred PM ewes was analysed. Non-
selected ewes born in 1984 and 1985 were
sheared at the age of 23 months, after
12-month growth of fleece. Housing and feed-
ing conditions within the same year were iden-
tical in the both genetic groups. The ewes were
fed according to the Institute of Zootechnics
standard (2), with farm-produced roughage
supplemented by commercially available con-
centrates.

The recorded data included: greasy and

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JOURNAL OF AGRICULTURAL SCIENCE IN FINLAND



clean wool yield, rendement, fibre length and
diameter analysed in a laboratory on samples
taken from the side, as well as wool charac-
ter subjectively evaluated in the whole fleece
on a 20-point scale, as a sum of the following
traits: evenness of assortment (maximum
score 5 points), stapling (max. 4), handle
(max. 3), crimp (max. 5) and yolk (max. 3).
On the basis of laboratory analysis of fibre
diameter, the percentage of fleeces in assort-
ments A and B (typical for the PM) was cal-
culated.

The computations were carried out on the
basis of arithmetic means and coefficient of
variation as well as double factor variance
analysis (breed and year) according to Rus-
ZCZYC (4).

Results and discussion

Crossbred ewes produced less greasy wool
than purebreds (table 1) the difference was
0.3 kg, i.e. 7.5 % (P<0.05). Their wool had,
however, considerably higher rendement (by
9.0 %, P<0.01) and, in effect, their clean
wool yield was 0.18 kg (8.2 %, P<0.05)
higher than that of the purebreds. At the same
time much variation was observed between the
years of birth. Ewes born in 1985 had a much
higher greasy wool production, while those
born in 1984 had a higher rendement; in ef-
fect, clean fleece weight was similar for both
years. The significant interaction breed X year
of birth in rendement was due to the fact that
in 1984 the difference in rendement between

Table 1. Wool performance of crossbred ewes (FnPMxPM) compared to purebred PM ewes.

Trait Statis-
tical

parame-
ters

Breed Year of birth Interac-
tionFxPM x PM PM XPM 1984 1985 breed x

year of
birth

No. of ewes n 180
Greasy wool (kg) x 4.0"

V% 20.3
Clean wool (kg) x 2.38*

V% 19.8
Rcndement (%) x 60.2A

V% 14.6
Fibre length (cm) x 11.4A

V% 19.1
Fibre diameter (um) x 24.8A

V% 8.3
Wool character score

evenness of assortment x 4.0*
V% 21.1

stapling x 2.9"
V% 36.2

handle x 2.0 A
V% 41.7

crimp x 3.4
V% 28.4

yolk x 2.6
V% 21.6

Total score x 14.9
V% 23.4

% of ewes with fleeces
in assortments A and B "In 82.8

aa—P<o.os
AA—P^O.OI

x—interaction significant at P^0.05

51 129 102
4.3“ 3.8A 4.5 A

20.8 19.5 17.0
2.20“ 2.34 2.34
20.5 21.4 18.8
51.2* 62.6 52.7 x
13.7 13.2 13.6
10.5* 11.0 11.2 x
17.0 21.0 17.1
23.9* 24.4A 24.9 A

8.6 8.78.8

4.2“
15.8
3.2“

28.0

4.2“ 3.9*
19.6 20.7
3.0 3.0

34.4 34.8
2.5A

26.7
2.2 2.0

38.4 40.4
3.5 3.6 3.3

25.1 25.6 30.0
2.6 2.7 2.6

18.5 21.6 19.8
16.0 15.6 14.7
17.4 21.7 22.1

92.2 84.3 87.3

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crossbreds and purebreds was much greater
than in 1985 (10.6 vs. 5.8 %).

Crossing withF considerably increased fibre
length and diameter. Wool of the crossbred
ewes was 12.2 % longer and 3.8 % coarser
than that of the purebreds (table 1); both
differences significant at P<o.ol. Differences
between ewes born in 1984 and 1985 were
much smaller, although significant for fibre
diameter. The interaction in fibre length was
significant, because it varied between the
genetic groups much more in 1984 than in
1985 (1.9 vs. 0.4 cm). The increase in fibre
diameter found in the crossbreds is also as-
sociated with a smaller percentage of wool in
assortments typical for the PM by 9.4 %
lower than in the purebreds (table 1).

Results of subjective appraisal of wool
character indicate a slight negative effect of
crossbreeding with F (table 1). Fleeces of the
PM had higher scores for evenness of assort-
ment, stapling and handle by 6.3, 9.9 and
26.1 *Vo respectively (signif.). Scores for crimp
and yolk were similar in the both groups. The
total score of PM fleeces was 7.2 % higher
(P<0.05) than that of the crossbreds. There
was no difference between ewes born in differ-
ent years in wool character, except for even-

ness of assortment which was 8.0 % higher
in ewes born in 1984.

The variation within the crossbred groups
for such traits as greasy and clean wool yield,
rendement and fibre diameter was not great-
er than the variation within the purebred PM
groups. In fibre length and wool character,
however, there was more variation within the
crossbred groups.

In general, the differences in wool perfor-
mance of ewes with 25 % F genotype, in com-
parison to purebred PM, were not very great
and, as was expected, much smaller than those
observed in F, ewes FxPM (3).

Conclusion

The analysis of wool performance of
crossbred ewes (F X PM X PM) did not show
any considerable difference in wool yield
(greasy wool production a little lower than in
purebreds, clean yield a little higher), but the
differences in wool quality and character were
more pronounced: greater rendement, fibre
length and diameterbut lower character score.
In sum, relatively small reduction in the per-
centage of fleeces classified in assortments
typical for purebred PM was observed
9.4 %.

References

1. Maijala, K., 1979. Experiences of Finnsheep and its
crosses as dams for fat lambs. Symposium on Inten-
sive Sheep Production. Helsinki, 2—9,

Dwustopniowe krzyzowanie towarowe owiec
merynosowych z trykami ras plennych i miesnych.
Sprawozdanie z realizacji tematu PR-4, 4712.3. 1Z
Krakow, ZZD Koluda Wielka.2. Normy zywienia zwierzqt gospodarskich, 1982.

PWRiL Warszawa. 4. Ruszczyc, Z., 1978. Metodyka doswiadczeri zootech-
nicznych. PWRiL Warszawa.3. Osikowski, M., Borys, B. & Korman, K., 1981.

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