Preservation of the fund of local breeds of agricultural animals, which are breeding material for the creation of new ones and the improvement of existing ones, meets the requirements of the FAO - the protection of biological diversity. The study of the genetic structure of cows of the local Lebedyn breed, which was bred in Ukraine, with the use of cytogenetic and molecular genetic methods, is aimed at establishing information about the structure of the gene pool of these animals and the uniqueness of their genotype.
Cytogenetic monitoring showed that the modal number of chromosomes corresponded to the species norm and was 2n=60, no constitutional abnormalities in the form of Robertsonian translocations were detected, the average frequency of genomic disorders (aneuploidy) was 10,2±2,10%, polyploidy was not manifested. structural disorders (chromosomal breaks) accounted for 3,1±1,88% and asynchronous separation of the centromeric regions of chromosomes – 0,8±0,10%. The average share of cytogenetic parameters of cells was determined: lymphocytes with micronucleus – 3,6±0,61‰, binucleus lymphocytes – 4,3±0,97‰ and mitotic index – 3,7±1,20‰.
An analysis of the genetic structure of the local, small-numbered Lebedyn cattle breed of Ukraine was carried out using 8 ISSR-systems. All 8 microsatellite primers showed high efficiency. ISSR labeling revealed 88 amplified DNA fragments, of which only 18 were polymorphic. The total share of polymorphic loci was 25,45%. 11 species-specific loci for (ACC)6G, 5 loci for (CTC)6C, 10 for (GAG)6C, 7 for (GA)6CC, 10 for (AG)8CG, 9 for (AG)8CA, 13 for (GA)9C and 14 for (AG)9C.
It was established that the studied animals were characterized by karyotype stability, reduced sensitivity to mutagenic factors of various nature, absence of inbreeding depression and reproductive isolation.
