Study of Correlations between Traits, Characterizing Wool Productivity in Sheep from the Karnobat Fine-wool Breed
Keywords:
sheep breeding, correlations, Karnobat fine-wool breed, heritabilityAbstract
The aim of the present study was to investigate the correlations between the traits characterizing
the wool production in sheep by Karnobat fine-wool breed. A study was carried out with two groups
of sheep at the age of 2.5 years from the herd of the Institute of Agriculture in Karnobat born in 2005
and 2015 year. The subject of the study is the controlled traits: wool productivity, clean wool, staple
length and live weight. It has been found that the correlation coefficients reflecting the dependencies
between the individual characteristics characterizing wool production are comparatively low under
the conditions of our study. The selection of the Karnobat fine-wool breed sheep can not be based
on a correlation effect, and selection should be carried out on each trait individually. The correlation
between wool productivity and clean wool in sheep born in 2005 and 2015 is positive and high in
value (r = 0.715 and r = 0.723). These values, however, do not reach the limit, after which we can select
only by wool productivity and ensure a high yield of clean wool. Heritability for the traits are low (h2
= 0.028 and h2
= 0.170), indicating that the genetic diversity of the herd is severely reduced and its
potential capabilities can not provide for future genetic progress.
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