Determination of Factors Influencing Birth Weight Using Regression Tree (Rt) Method

Abstract

This study was conducted to evaluate the effects of genotype, sex, birth type and year and dam age on birth weight by applying regression tree method using 101 Karakas and 103 Norduz lambs raised at Research and Application Farm of the Faculty of Agriculture, Yuzuncu Yil University, Van, Turkey. The effect of sex on single-lambs was significant, whereas, genotype had a significant effect on twin-lambs. The heaviest mean birth weight was obtained by single-male lambs, but twin-lambs born by dam of 2, 3 and 6 years age in the Norduz breed had the lowest mean birth weight.