Phenotypic analysis of egg production in two strains of White Leghorn under reciprocal recurrent selection
R. K. MISHRA, KULDEEP KHANNA, F.P. SAVALIYA, R.S. JOSHI, V.N. BAROT
AND A.B. PATEL
Poultry Complex, Veterinary College
Anand Agricultural University, Anand – 388 110
The records from a total of 879, 1551, 1395, 2080 and 1911 pullets from S 1, S 2, S 3, S 4 and S 5 generation respectively were considered for statistical analysis. Over the generations number of pullets under DD, DK, KK and KD genetic groups were 1819, 2048, 1650 and 2229 respectively. Overall least squares mean (LSM) of EN 40 was 98 with 17 % of variation, while for lines DD, KK, DK and KD average egg number being 98, 96, 100 and 99 eggs. LSM for lines DD, KK, DK and KD were 89.75, 87.46, 92.95 and 92.51 for S 1 generation and 107.11, 101.50, 112.83 and 111.49 eggs into S 5 generation respectively. Pure line as well crosses differed significantly from each other. Over the generations there was improvement in egg number except in generation four. The comparison of means among five generations indicated that the performance of purebreds as well as crossbreds in S 5 generations were found to be superior over other generations (P < 0.05), except the performance of KK at S 3 generation. In general, crosses performed better than pure (P < 0.05) over the generation both in DD versus DK and KK versus KD.