EVALUATION OF PRODUCTIVE TRAITS OF CHICKEN LINES FROM THE NATIONAL GENE POOL.

The issue of avian gene pool preservation should be linked to the development of a new trend in selection allowing rational use of the diversity of breeds and lines. Ten original chickens lines are reared in the Poultry Breeding Unit at the Institute of Agriculture, Stara Zagora: ?Z-80 B, ?Z-80 ?, Line ?, Line D, Line G, Line NG, Line ?, Line Ss, Line ChS, Line StR controlling their productivity through reproductive traits, live body weight at the age of 1 day, 5 months and 10 months, egg production and survival rate for the production period. The reproductive traits of chickens from the gene pool are characterized with high egg fertility - from 96.56% for Line NG t? 86.98% of Plymouth Rock Line G. Among the egg-type chicken lines, the highest hatchability rate from fertile eggs was observed in Line D - 89.05%. Chickens of all lines studied exhibited low death rates. The highest egg mass was that of chickens from Line G - 63.10 g and Line ? - 61.73 g The highest egg production over the 180-day period was that of the egg-type Line ? - 146 eggs, and Line ?Z-80 B - 145.67. [ABSTRACT FROM AUTHOR]