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СЕЛСКОСТОПАНСКА АКАДЕМИЯ ● ЖИВОТНОВЪДНИ НАУКИ, LVIII, 2/2021 13
Productivity assessment of sheep from the Karnobat Fine
Fleece Breed by genealogical lines
Margarit Iliev1*, Genoveva Staykova2, Georgi Anev3, Todor Tsonev3
1 Institute of Agriculture – Karnobat
2 Agricultural Institute – Shumen
3 Research center for Agriculture – Targovishte
*Corresponding author: mar_iliev@abv.bg
Citation: Iliev, M., Staykova, G., Anev, G., & Tsonev, T. (2021). Productivity assessment of sheep
from the Karnobat Fine Fleece Breed by genealogical lines. Zhivotnovadni Nauki, 58(2), 13-19 (Bg).
Abstract
Subject of the study were 341 sheep from the Karnobat Fine Fleece breed, ownership of the
Institute of Agriculture – Karnobat. The productivity of animals born between 2013 and 2017 was
analyzed. The genealogical structure of the ock included 3 breeding lines – 777, 2081 and 1825. The
main selection traits that were studies were: live weight at weaning, at 1.5 years and 2.5 years, wool
yield and staple length at 1.5, 2.5 and 3.5 years, clean wool yield and clean bre at 1.5 and 2.5 years.
This information was collected from the Pedigree book of the farm. The data were obtained through
standard methods and instructions provided in the Instruction for control of productive traits (2011),
issued by the Association for Breeding Fine Fleece Sheep in Bulgaria. The following measurements
were made: 951 measurements of live weight, 870 measurements of wool yield and staple length and
579 samples were analyzed for clean wool yield and clean bre. The data were processed according to
the variation statistics methods and adjusted for the inuence of the year. The study on the Karnobat
Fine Fleece breed reported a positive lineage effect for the 1825 line for live weig ht at 1.5 and 2.5 years
– 54,100 kg and 59,230 kg and for staple length at all ages – 13.62, 11.52 and 11.40 cm. Animals from
the 2081 line exhibited higher results for the wool yield trait – 7.950 kg and 7.280 kg, clean wool yield
trait – 65.81% and 66.50% and clean bre trait – 5.230 kg and 4.840 kg at 1.5 and 2.5 years. Minimal
linear differentiation on the basis of live weight and wool productivity traits in sheep of the Karnobat
Fine Fleece breed was found. Narrowed genetic diversity does not allow successful selection and
genetic progress on the studied traits in the population.
Key words: Karnobat ne eece breed, genealogical lines, live weight, wool yield, clean wool
yield, clean bre
Оценка на продукстивността на овце от Карнобатската тънкорунна
порода по генеалогични линии
Маргарит Илиев1*, Геновева Стайкова2, Георги Анев3, Тодор Цонев3
1Земеделски институт – Шумен,
2Институт по земеделие – Карнобат,
3Научен център по земеделие – Търговище
*Автор за кореспонденция: mar_iliev@abv.bg
СЕЛСКОСТОПАНСКА АКАДЕМИЯ ● ЖИВОТНОВЪДНИ НАУКИ, LVIII, 2/202114
Резюме
Обект на проучването са 341 овце от Карнобатската тънкорунна порода, собственост на ИЗ
– Карнобат. Изследвана е продуктивността на животните, родени в периода 2013–2017 година.
Генеалогичната структура на стадото включва 3 развъдни линии – 777, 2081 и 1825. Проучени
са основните селекционни признаци: живо тегло при отбиване, на 1,5 и 2,5 години, вълнодо-
бив и дължина на щапела на 1,5, 2,5 и 3,5 години, рандеман на вълната и чисто влакно на 1,5
и 2,5 годишна възраст. Информацията е получена от Родословната книга на фермата. Данните
са получени по стандартните методи и указания предвидени в Инструкцията за контрол на
продуктивните признаци (2011) от Асоциацията за развъждане на тъкорунните овце в Бълга-
рия. Направени са 951 измервания на живо тегло, 870 на вълнодобив и дължина на щапела и
579 проби са изследвани за рандеман и чисто влакно. Данните са обработени по методите на
вариационната статистика и коригирани за влияние на годината. Проучването на Карнобат-
ската тънкорунна порода овце отчита положителен ефект на линейната принадлежност при
линия 1825 за живо тегло на 1,5 и 2,5 години – 54,100 kg и 59,230 kg и за дължина на вълната
на всички възрасти – 13,62, 11,52 и 11,40 cm. Животните от линия 2081 показват по-високи ре-
зултати за признаците вълнодобив – 7,950 kg и 7,280 kg , рандеман – 65,81% и 66,50% и чисто
влакно – 5,230 kg и 4,840 kg на 1,5 и 2,5 години. Установена е незначителна линейна диферен-
циация по признака живо тегло и признаците на вълнодайната продуктивност при овце от
Карнобатската тънкорунна порода. Стесненото генетично разнообразие не предполага успеш-
на селекция и генетичен прогрес по изследваните признаци в популацията.
Ключови думи: Карнобатска тънкорунна порода, генеалогични линии, живо тегло,
вълнодобив, рандеман, чисто влакно
Introduction
The reduction of the number of sheep in our
country over the last three decades has mostly
affected Fine Fleece sheep breeding. Purebred
linear breeding is the main method for selection
when preserving endangered breeds. The Kar-
nobat Fine Fleece breed is highly endangered
and the only herd of this breed is raised at the In-
stitute of Agriculture in Karnobat. At this criti-
cal volume, it is necessary to look for options to
preserve and reduce the level of homozygosity
in the population. Studies of the main productive
traits in genealogical lines in Fine Fleece sheep
breeds in Bulgaria have been made by Boyk-
ovski et al. (2009, 2012, 2015; 2018); Dimitrov
(2006); Panayotov et al. (2000); Slavova (2000);
Slavova et al. (2012, 2016); Slavov (2007); Stayk-
ova, Stancheva (2010); Stancheva et al. (2015);
Tsonev (2014). The phenotypic and genotypic
parameters of the Karnobat Fine Fleece sheep
breed were studied by Antonova (1973); Ba-
levska et al. (1979); Dimitrov (1987); Iliev et al.
(1999, 2001, 2010, 2017, 2019); Lazarov (1981);
Mihailova et al. (1979). The analyzes of the pro-
ductivity in the nucleus ocks of the breeds con-
tribute to the formation of a new breeding strat-
egy in the Fine Fleece sheep breeding, as well as
to the economic survival of the ocks. Our au-
thors recommend the incorporation of the three
breeds in the Bulgarian Fine Fleece breed, with
preserved, differentiated interbreed types. This
raises the need for current research and moti-
vates our development.
The purpose of this study is to assess the pro-
ductivity of sheep from the Karnobat Fine Fleece
breed by genealogical lines.
Material and methods
Subject of the study were 341 sheep from the
Karnobat Fine Fleece breed, ownership of the In-
stitute of Agriculture – Karnobat. The productiv-
СЕЛСКОСТОПАНСКА АКАДЕМИЯ ● ЖИВОТНОВЪДНИ НАУКИ, LVIII, 2/2021 15
ity of animals born between 2013 and 2017 was
analyzed. The genealogical structure of the ock
included 3 breeding lines – 777, 2081 and 1825.
Animals of line 777 – 134 had the largest rela-
tive share (39.3%) of the entire herd. The ances-
tor of the line is a purebred breeder of the Aus-
tralian Merino breed, imported from Australia.
The institute used seed material from it, obtained
in Regional Directorate for Selection and Re-
production in Animal Husbandry – Targovishte.
Line 2081 has 118 animals (35.8%) and originates
from a ram with 50% Australian blood from the
Veselinovo village, Yambol region. The third line
is 1825 with 85 sheep (24.9%) of the herd. This
line originated from a breeder ram of the North-
east Bulgarian ne Fleece breed, purchased from
Devnya, Varna region. Selection traits that were
included in the study were: live weight at wean-
ing, at 1.5 and 2.5 years, wool yield and staple
length at 1.5, 2.5 and 3.5 years, wool yield and
clean ber at 1.5 and 2.5 years. The information
was obtained from the Pedigree book of the farm.
The data were obtained according to the standard
methods and guidelines provided in the Instruc-
tion for control of productive traits (2011) by the
Association for Breeding of Fine Fleece Sheep in
Bulgaria. 951 measurements of live weight, 870
measurements of wool yield and staple length
were made and 579 samples were tested for yield
and clean ber. Live weight was measured to the
nearest 0.5 kg, taking into account the exact age
in days at weaning, for comparability of data.
The amount of wool obtained was determined
individually and measured to the nearest 0.1 kg.
To determine the wool yield and to calculate the
clean ber, samples of 50 g of wool were taken.
The receipt of the materials and the research was
carried out according to the methodology applied
in the laboratory of wool science in the town of
Shumen. The data were processed according to
the methods of variation statistics and were ad-
justed for the inuence of the year.
Results and discussion
Data on live weight, wool yield and staple
length traits based on lines and the effect of lin-
eage are given in Table 1. Lambs with the highest
live weight at weaning were those from line 777
(24.770 kg). At 1.5 and 2.5 years of age, sheep
from line 1825 were statistically superior to other
lines (54.100 kg and 59.230 kg) (P < 0.001). The
animals of line 2081 (P < 0.01) had lower live
weight at all studied ages. The average weight
of the studied ages in our study has lower val-
ues than the results of Dimitrov (1987) and Iliev
(2001, 2010) for the same levels. Slavov (2007)
also reported higher live weights at weaning, at
1.5 and 2.5 years in the Dobrudzha-type sheep
of the North East Bulgarian Fine Fleece breed.
Slavova (2019) gave data with higher average
weight at weaning, which in the following ages
was lower in t he T hracian Fine Fleece breed. Tso -
nev (2014) published similar values for the trait in
the nucleolus herds of the Fine Fleece population.
Stancheva et al. (2015) found that the average val-
ues of live weight in Fine Fleece sheep from the
ocks of the Agricultural Academy ranged from
46.800 to 53.400 kg in sheep in 18 months and
from 55.800 to 65.100 kg in ewes. Boykovski et
al. (2018) reported a higher live weight at weaning
of the Shumen type of North East Bulgarian Fine
Fleece breed. Our results indicate that the differ-
ences in the live weight trait, based on lineage,
were minimal. The phenotypic variation was sig-
nicantly higher at weaning (from C = 12.31% to
C = 12.73%) which can be explained by the effect
of the mother on the growth abilities. Selection
intensity also had an effect and during the follow-
ing ages it decreased.
Offspring of line 2081 gave larger amounts
of unwashed wool up to 2.5 years of age (7.950
kg and 7.280 kg) (P < 0.001, P < 0.05) (Table
1). The animals from line 1825 performed lower
than their peers on the rst shearing, after which
they gave average results on the second and sig-
nicantly higher wool yield at 3.5 years (6.930
kg) (P < 0.001). Sheep from the 777 line had
signicantly lower amounts of unwashed wool
at 2.5 and 3.5 years (P < 0.001, P < 0.01). The
variation coefcient values for wool production
were relatively low and indicated that the differ-
ences between the lines were insignicant and
the results were multidirectional. Slavov (2007)
reported analogous to our results for the North
СЕЛСКОСТОПАНСКА АКАДЕМИЯ ● ЖИВОТНОВЪДНИ НАУКИ, LVIII, 2/202116
Таблица 1. Живо тегло, вълнодобив и дължина на щапела по линии
Table 1. Live weight, wool yield and staple lenght in line
Линии /
Line
Признаци – възраст
Traits – age
nx ± SxC
ефект на
линията /
effect at line
nx ± SxC
ефект на
линията /
effect at line
nx ± SxC
ефект на
линията /
effect at line
1. Живо тегло, кg
1. Live weight, кg
при отбиване /
at weaning
на 1.5 години /
at 1.5 years
на 2.5 години /
at 2.5 years
777 134 24.77 ± 0.26 12.31 0.35 127 53.40 ± 0.23 4.78 -0.09 114 58.67 ± 0.25 4.52 -0.08
2081 12 2 23.94** ± 0.28 12.73 -0.48 117 53.16 ± 0.24 4.80 -0.33 103 58.07** ± 0.26 4.57 -0.52
1825 85 24.55 ± 0.33 12.42 0.13 81 54.10*** ± 0.28 4.72 0.61 68 59.23*** ± 0.32 4.48 0.64
Общо средно /
Average 341 24.42 ± 0.17 12.48 325 53.49 ± 0.14 4.77 285 58.59 ± 0.16 4.53
LSD 0.39 0.34 0.39
2. Вълнодобив, кg на 1.5 години / на 2.5 години / на 3.5 години /
2. Wool yield, кg at 1.5 years at 2.5 years at 3.5 years
777 127 7.83 ± 0.07 9.81 0.07 115 7.03** ± 0.07 10.26 - 0 .13 103 6.39*** ± 0.06 10.27 -0.25
2081 11 8 7.95*** ± 0.07 9.66 0.19 104 7. 28 * ± 0.07 9.90 0.12 91 6.73 ± 0.07 9.75 0.09
1825 83 7.3 9 *** ± 0.08 10.39 -0.37 70 7.18 ± 0.09 10.04 0.02 59 6.93*** ± 0.09 9.47 0.29
Общо средно /
Average 328 7.76 ± 0.04 9.90 289 7.16 ± 0.04 10.07 253 6.64 ± 0.04 9.88
LSD 0.10 0.11 0 .11
3.Дължина на щапела, cm
3. Staple length, cm
на 1.5 години /
at 1.5 years
на 2.5 години /
at 2.5 years
на 3.5 години /
at 3.5 years
777 127 13.07 ± 0.19 16.21 -0.25 115 11.11 ± 0.16 15.92 - 0.14 103 10.92 ± 0.15 13.62 -0.21
2081 119 13.37 ± 0.19 15.85 0.05 104 11.22 ± 0.17 15.77 -0.03 91 11.19 ± 0.16 13.29 0.06
1825 83 13.62* ± 0.23 15.56 0.30 69 11.52 * ± 0.21 15.36 0.27 59 11.40* ± 0.19 13.04 0.27
Общо средно /
Average 329 13.32 ± 0.12 15.91 288 11.25 ± 0.10 15.72 253 11.13 ± 0.09 13.36
LSD 0.28 0.26 0.26
* – P < 0.05; ** – P < 0.01; *** – P < 0.001
СЕЛСКОСТОПАНСКА АКАДЕМИЯ ● ЖИВОТНОВЪДНИ НАУКИ, LVIII, 2/2021 17
East Bulgarian Fine Fleece breed, and Slavova
(2019) indicated lower values for wool yield in
the Thracian Fine Fleece breed of the same ages,
respectively by 4%, 16% and 8%. Tsonev (2014)
found an average wool yield from 7.740 kg to
8.440 kg in Fine Fleece sheep in 18 months.
The data analysis on staple length (Table 1)
indicates that it is in accordance with the require-
ments of the breed. The staple length of sheep in
18 months from line 1825 was signicantly lon-
ger (13.62 cm) (P < 0.05), and line 777 had the
shortest. At 2.5 and 3.5 years this tendency con-
tinued. The trait was characterized by the high-
est values in sheep from line 1825 of all stud-
ied ages (13.62, 11.52 and 11.40 cm) (P < 0.05).
The animals from line 2081 give data for levels
around the mean with various insignicant de-
viations, without statistical certainty. The values
of the coefcients of variation for average wool
length were low to medium and showed insignif-
icant variation between the different lines of the
studied ages. Sheep from the Trakia Fine Fleece
breed have a longer staple length at 18 months
– 14.567 cm, but with age the data ranged from
9.08 to 9.40, which was lower compared to our
results (Slavova, 2019). Slavov (2007) also re-
ported lower results on this basis for the North
East Bulgarian Fine Fleece breed. Stancheva et
al. (2015) indicated an average staple length in
sheep in 18 months and ewes, from 10.06 cm to
14.40 cm and from 9.10 cm to 10.68 cm, respec-
tively, of Fine Fleece ocks raised in the insti-
tutes of the Agricultural Academy.
The comparison between the three lines in our
study showed that line 1825 had a positive devia-
tion from the average for the studied sample of the
live weight and staple length traits at all studied
levels. The sheep from line 2081 were character-
ized by higher values of wool yield at the studied
ages, which was probably due to the better densi-
ty of wool. Line 777 presented the highest growth
rate in lambs up until weaning, without statistical
signicance, and for the other indicators indicat-
ed medium to low levels of the studied selection
traits. Iliev (2010) found a signicant superiority
of the offspring of line 777 in live weight, staple
length and yield of the wool. According to the
same author, line 1825 was presented with a posi-
tive deviation from the average for the amount of
wool and the obtained pure ber.
Таблица 2. Рандеман на вълната и чисто влакно по линии
Table 2. Clean wool yield and clean bre in line
Линии /
Line
Признаци – възраст /
Traits – age
nx ± SxС
ефект на
линията /
effect at line
nx ± SxС
ефект на
линията /
effect at line
1. Рандеман на вълната, % на 1.5 години на 2.5 години
1. Clean wool yield, % at 1.5 years at 2.5 years
777 118 63.25*** ± 0.61 10.45 -1.43 113 64.28 ± 0.68 11.28 -1.00
2081 109 65.81** ± 0.63 10.05 1.13 100 66.50* ± 0.73 10.91 1.22
1825 75 65.28 ± 0.76 10.13 0.60 64 65.14 ± 0.91 11.13 - 0.14
Общо средно / Average 302 64.68 ± 0.38 10.22 277 65.28 ± 0.44 11.11
LSD 0.89 1.11
2. Чисто влакно, kg
2. Clean bre, kg
на 1.5 години
at 1.5 years
на 2.5 години
at 2.5 years
777 118 4.950 ± 0.07 15.39 -0.07 113 4.520** ± 0.07 16.26 - 0 .15
2081 109 5.230*** ± 0.07 14.57 0.21 100 4.840*** ± 0.07 15 .19 0.17
1825 75 4.830*** ± 0.09 15.78 - 0.19 64 4.680 ± 0.09 15.71 0.01
Общо средно / Average 302 5.020 ± 0.04 15.18 277 4.670 ± 0.04 15.74
LSD 0.10 0.11
* – P < 0.05; ** – P < 0.01; *** – P < 0.001
СЕЛСКОСТОПАНСКА АКАДЕМИЯ ● ЖИВОТНОВЪДНИ НАУКИ, LVIII, 2/202118
The obtained data for wool yield and clean
ber traits along the lines and the effect of the
line are reected in Table 2. The analysis of
wool yield indicated high results in sheep in 18
months and in ewes at the age of 2.5 years, which
exceed the requirements for the breed. The sheep
from line 2081, which originates from the Aus-
tralian Merino breed, performed better in the
two studied ages (65.81% and 66.50%) (P < 0.01,
P < 0.05). The animals from line 777 have lower
results on this basis, and those from 1825 gave
small and varied uctuations around the average
without statistical signicance. The variation
between the individual lines was minimal. The
same trend was maintained in the analysis of
the results for the obtained clean ber (Table 2).
Line 2081 dominated its peers, with an average
of 5.230 kg and 4.840 kg of clean ber at 1.5 and
2.5 years, respectively (P < 0.001). The animals
from line 777 (P < 0.01) had lower results, and
those from 1825 were presented with multidi-
rectional and close to the average deviations for
the group of studied animals. The variation co-
efcients values ranged from 14.57% to 16.26%
and showed minimal differences between lines
without signicance. The Karnobat Fine Fleece
sheep breed in our study was characterized by a
higher yield and amount of clean ber, compared
to the results of Slavov (2007) for the Northeast-
ern Bulgarian Fine Fleece breed, Staykova et al.
(2010) for the Askanian, Iliev (2010) for the same
breed and Tsonev (2014) for the three Bulgarian
Fine Fleece breeds. The average levels of these
selection traits exceeded those stated in the re-
port of the Association for breeding Fine Fleece
sheep in Bulgaria for 2019, summarized for the
entire Fine Fleece population in our country. The
established minimal signicant and insignicant
linear differentiation in the studied herd showed
that it will be hardly possible to conduct success-
ful selection on these productive traits.
Conclusions
The study of the Karnobat Fine Fleece sheep
breed reported a positive effect of the lineage in
line 1825 for live weight at 1.5 and 2.5 years –
54.100 kg and 59.230 kg and for wool length at
all ages – 13.62, 11.52 and 11.40 cm.
The animals from line 2081 showed higher
results for the wool yield trait – 7.950 kg and
7.280 kg, clean wool yield – 65.81% and 66.50%
and clean ber – 5.230 kg and 4.840 kg at 1.5 and
2.5 years.
Minimal linear differentiations were found
on the basis of live weight and the wool produc-
tivity traits in sheep of the Karnobat Fine Fleece
breed. Narrowed genetic diversity does not im-
ply successful selection and genetic progress on
the studied traits in the population.
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