Cytogenetic and <i>ISSR</i>-Markers Polymorphism in the Population of Local Ukrainian Lebedyn Cows

The preservation of the fund of local breeds of agricultural animals, which are breeding materials for the creation of new ones and the improvement of existing ones, meets the FAO requirements, which are the protection of biological diversity. The study of the genetic structure of cows of the local Lebedyn breed, which was bred in Ukraine, using 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, constitutional abnormalities in the form of Robertsonian translocations were not 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‰. The genetic structure of Ukraine's local, small-numbered Lebedyn cattle breed was analyzed using 8 <em>ISSR</em> systems. All 8 microsatellite primers showed high efficiency. <em>ISSR</em> labeling revealed 88 amplified <em>DNA</em> fragments and only 18 of them were polymorphic. The total number of polymorphic loci was 20.45%. 11 species-specific loci for <em>(ACC)<sub>6</sub>G</em>, 5 loci for <em>(CTC)<sub>6</sub>C</em>, 10 for <em>(GAG)<sub>6</sub>C</em>, 7 for <em>(GA)<sub>6</sub>CC</em>, 10 for <em>(AG)<sub>8</sub>CG</em>, 9 for <em>(AG)<sub>8</sub>CA</em>, 13 for <em>(GA)<sub>9</sub>C</em> and 14 for <em>(AG)<sub>9</sub>C</em> were found in the cows of Lebedyn cow breed. It was established that the experimental animals were characterized by karyotype stability, reduced sensitivity to mutagenic factors of various natures, high genetic consolidation, and reproductive isolation.