Determining genetic similarity and genetic diversity in selected Alexandria chickens using rapd technique

Abstract

The Alexandria chicken considered as one of our Egyptian local strain. A lot of attempts were done to improve productive traits. A control line (or a base line) and another selected one are derived from this local strain. The selected line subjected to a long term selection program lasted for 16 generations from 1995 to 2011 in order to improve some egg production traits and also to reach earlier sexual maturity. This long term selection program expected to reduce most of the variations in this closed population which normally reflected on the response of selection. So, the main target was to estimate the genetic similarities by calculating the genetic improvement occurred during different generations. RAPD analysis technique used to estimate the degree of diversity and stability for this selected line. The mean average percentage differences (MAPD), genetic similarity, genetic distance based on band frequencies or based on band sharing which had been estimated for Alexandria selected and control lines. The mean average percentage difference (MAPD) into Alexandria selected and control lines recorded 0.415 and 0.667 respectively. While, genetic similarity had recorded into selected line (0.635) and into control line (0.351). The genetic distance had been calculated by two methods, the first method calculated the genetic distance on the basis of band frequency recorded 0.46. This result explained the genetic identity index of selected and control Alexandria lines. While the second method calculated the genetic distance on the basis of band sharing recorded 0.41. The phylogenetic relationships within 12 samples randomly taken from Alexandria selected line cleared that the degree of similarity reached 80% within line from primer 1 ,70% from primer 2 ; 65% from primer 3,50% from primer 4; 55% from primer 5 and 60% from primer 6. While; this similarity when calculated within samples into line each primers recorded approximately %63. The results of this present research concluded that, the Alexandria selected line did not consume some of the variability present in this studied population and did not yet reach genetic stability. So, it can to continue the selection program.