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Abstract

Improving the efficiency of breeding for fox’s reproductive qualities advasing is associated with the selection of individuals with certain economically useful traits and evaluated for their ability to transfer and fix ones in subsequent generations. A combining ability of parental lines determination, as well as individual characteristics of animals, is paramount. The factors characterizing the contribution of each parents, as well as their combination with each other in the formation of the descendant’s productive potential, are the combinational capacity components, which are disclosed on the basic fur animal farming of Kharkiv region.
The analysis of six lines of the breeding core of silver-black foxes was carried out and the general and specific combining ability of maternal and paternal forms were determined by fertility. The probable influence of the specific combining ability of the combinations to the studied parameter was established, which allowed a clear differen-tiation of the lines according to the level of fertility: improvers, neutral and degraders. In addition to the obvious fundamental value, the information obtained is also important practical point of view. In particular, it was concluded that it is advisable to use indi-vidual representatives of the lines, as well as the most promising options for combinations of parental pairs. Using components of combining ability, outsiders are defined, which should be excluded from the further selection process. The actual research materials illustrate the results of dispersive analysis of differences in fertility of females, average fertility rates of combinations of maternal and paternal lines, combination capacity of lines, effects of general combining ability, constants and variants of specific combination ability of linear foxes.

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