Restriction selection indices for genetic improvement of a commercial stain of White Leghorn
MAROOF AHMAD, HARPAL SINGH AND R.K. SHARMA
Department of Genetics and Animal Breeding ,College of Veterinary and Animal Sciences
G. B. Pant University of Agriculture and Technology
Pantnagar – 263 145, Uttaranchal
The present study was undertaken on 559 pullet progenies from 149 dams mated with 58 sires produced in a single hatch of a White Leghorn strain and maintained by a poultry breeding organization were used. Body weights at 12 and 36 week of age, age at sexual maturity, egg production up to 280 days and 32-week egg weight were utilized to construct restriction selection indices in various combinations. Though the general selection index, I 1, which was constructed using all the five traits, was found to be most superior index in terms of ∆H (44.98 units) and r IH (0.41) values, its use seems unlikely as it will decrease both egg production and egg weight. Complete restriction on 36-week body weight alone or in combination with 12-week body weight reduced the efficiency and accuracy of the index the most. All the restricted selection indices were found inferior to standard selection index (I 1). However, use of RI 1, is recommended for overall genetic improvement of the flock.