Selection indices for improving weaning weight of friesian male calves Egypt

Document Type : Original Articles

Abstract

The main purpose Of this paper is to construct different selection indices (general index, and reduced indices) to improve weaning weight at 90 days of age for Friesian male calves in Egypt by using oollected data from 1400 records during 10 years (1995• 2004 for body weights at brith (BW) and for 30 (W30). 60 (W60) and 90 (W90) days of age at the experimental farm of Facuily oj Agriculture, Minuflya University. The secondary objective is to evaluate and predict genetic parameter estimates of the previous traits. Overall means for the previous traits were 33,82. 42.08. 55.21 and 82.98 kg respectively, Herttability estimates for the previous traits were 0.28, 0.31 • .40 and 0.16. respectively. Significantly estimates of genetic correlations (rG) and phenotypic correIations (rP) among previous traits were positive. Fifteen selection indices were constructed, index {4) gave high (RIH} and (RE) values comparing with general index {11}. from this study, it could be concluded that genetic improvement for weaning weight of Friesian male calves could be achieved through multiple trait selection index. Therefore, it
could be suggested using (11 and 14) to improve weaning weight in friesian male calves under the large scale

Main Subjects