EFFECT OF DIFFERENT SOURCES OF SPECIFIC VARIABILITY ON THE WEIGHT DEVELOPMENT AND WOOL PRODUCTIVITY IN SHEEP FROM THE KARAKACHAN BREED

G. Staykova, M. Yosifov

Abstract: An investigation with 314 sheep from the Karakachan breed during the period 2003-2010, originated from Kabiuk herd, Shumen was carried out. Parameters live weight at weaning, 9 months, 1.5 years and 2.5 years of age, wool productivity traits - quantity and wool length at the age of 1,5 years were studied. The information was obtained from the origin books of the breed. All the evaluations and analyses were based on multi-factor linear - statistical models (Harvey, 1990): Y ijklm = μ + A ijklmno + B pqhij + e ijklm. The differences between the levels of the studied factors are established on the base of the arrangement degree, measured by Student (Hayter, A., 1984): yi - yj) / S √( 1/ni + 1/nj) /2. It was established the year of birth was a significant source of specific variability (Р≤0.001) for the traits live weight, wool yield and staple length of all studied ages. The breeding line has a significant influence on the trait live weight at weaning (Р<0.05). Effect of the breeding line for the traits characterising the wool productivity was not established. The established heritability coefficients of live weight at different age (h2 =0.211, h2 =0.259, h2 =0.402, h2 =0.168), wool yield and wool length at 18 months are low to average values (h2 =0.245 and h2 =0.069).

Keywords: breeding lines; Karakachan breed; live weight; wool yield; year of birth

Date published: 2017-05-16