IMPORTANT FACTORS IN THE SUCCESSFUL SHEEP BREEDING

Abstract

Qualitative traits are determined by one or more hereditary factors, and the influence of the environment on their variability is very small. In the case of traits whose hereditary basis is the result of the action of several genes, a qualitative form of inheritance also occurs. On that occasion, one or several genes appear with very clear effects, while the influence of other genes is insignificant. Breeding and selection of sheep depending on the nature of gene interaction, quantitative traits are inherited according to the type of additive, dominant and epistatic principles. Traditional methods of sheep breeding are increasingly complemented by modern selection methods-DNA analyses, in order to detect genes that influence the expression of certain production traits, or are located in the genome near the place responsible for a given trait. We will briefly discuss these problems.