Abstract
The study was conducted with an attempt i) to assess the productive and reproductive performances of three
Indigenous Chicken genotypes under intensive management, ii) to estimate variance, covariance components
and genetic parameters of economic traits of Indigenous Chicken genotypes, iii) to predict responses in
selecting to improve three Indigenous Chicken genotypes and iv) to estimate realized responses to selection to
improve 3 Indigenous Chicken genotypes under intensive management. A total of 4688 eggs (Naked Neck1683, Hilly- 1546 and Deshi-1459) were collected from different parts of Bangladesh to establish a foundation
stock. Chicks were hatched in two batches, two weeks apart from June 13 to 26 June 2010. A total of 1585 dayold chicks were used to establish foundation stock comprising of 918 Deshi, 378 Hilly and 289 Naked Neck. A
total of 1439 progeny (Non-descript Deshi=628, Hilly= 475 and Naked Neck= 336) were hatched in three
batches in first generation (G1), 1643 progeny (Non-descript Deshi=926, Hilly= 383 and Naked Neck= 334) were
hatched in two batches in second generation (G2) and 1278 progeny (Non-descript Deshi=655, Hilly= 303 and
Naked Neck= 320) were hatched in two batches in third generation (G3). In every generation, selection was
practiced at 2 (two) stages of birds life; firstly at 8 weeks of age, selection was performed on the basis of their
breeding value for 8-week body weight. Secondly, at 40-week of age, on the basis of an index comprising the
age at first egg laid, body weight at 40 week, egg production up to 280 days and egg weight at 40 weeks. Data
collected on birds of three generations were analyzed by General Linear Model procedure of SPSS 11.5 version
program to find out the least squares means and significance of fixed factors in each trait which was sex, batch,
generation and genotype. For genetic analysis, VCE for genetic parameters and PEST for breeding value
estimation were used. The least square means of egg weight, chick weight and chick egg ratios were 43.5±0.1g,
28.7±0.1g and 66.0±0.1%, respectively. Male chicks were significantly (p<0.001) heavier in body weights at 8th,
12th and 16th weeks when compared to the females under the same management. The average body weights of
Non-descript Deshi, Hilly and Naked Neck were 1074±4.0, 1279.6±5.5 and 1041.0±5.7g, respectively at the age
of 16 weeks. From 0-4, 0-8, 0-12, 0-16, and 0-first egg, the mean daily body weight gain ranged from 4.6 to 5.1,
7.3 to 8.6, 8.8 to 10.6, 9.0 to 11.1 and 7.4 to 9.5g, respectively for Naked Neck and Hilly genotypes. The highest
fertility was observed in G2 (90.2%). The Naked Neck had the lowest hatchability (p<0.001) on fertile eggs.
Genotype, generation and batch had significant (p<0.001) effect on age at first egg. The average 315 days egg
production of Indigenous Chickens was between 74.0-83.9 eggs under intensive system of rearing. The overall
mean of hen-day egg production and hen-house egg production per cent were 47.8±0.2 and 44.7±0.2,
respectively. Feed intake was influenced (p<0.001) by genotype, generation and genotype x generation
interaction. There was no difference in dressing per cent due to generation but there was highly significant
(p<0.001) difference in dressing per cent due to genotype. Slaughter age had highly significant (p<0.001) effect
on dressing per cent. There were significant (p<0.001) differences in external egg quality traits such as egg
length, egg width and shape index among the genotypes. The internal egg quality traits such as Haugh unit,
albumen index, albumen height, yolk index had significant (p<0.001) differences among the genotypes.
Observed performances indicated that Non-descript Deshi chicken would be suitable for egg production and
Hilly chicken for meat purposes. Heritability estimates of body weight traits taken at different ages in different
genotypes were medium to moderately high ranging from 0.23 to 0.50. The heritability values estimated in this
study for egg production and egg weight at 40 weeks of age were also high (0.35 and 0.50) in all genotypes. The
heritability estimates of age at first egg were high ranging from 0.40 to 0.46 but were very low to medium for
hatchability (0.02 to 0.18). Direct genetic and phenotypic correlations between age at first egg and egg weight at
40 weeks of age were mostly low and positive (0.06 and 0.04), but significantly negative between age at first egg
and egg production at 40 weeks of age (-0.12 and -0.33). On the other hand, the genetic and phenotypic
correlations between egg weight and egg production at 40 weeks of age were significantly negative (-0.22 and -
0.10). However, negative and low correlations (rc= -0.12; rp= -0.01) were observed between body weight at 40
weeks of age and egg production up to 40 weeks. The expected responses to 8 week body weight (g) in three
generations in three genotypes of male birds were positive which ranged from 17 to 82g and higher than female
(ranging from 7 to 34g). The expected responses in egg production (%) to 280 days were positive and higher
(2.28 to 3.59%) in generation 2 than in foundation generation (1.83 to 3.10%). The age at first egg were
predicted to decrease by -0.56, -2.21 and -0.67 days, respectively for Non-descript Deshi, Hilly and Naked Neck
in foundation generation, while those of -0.35, -0.77 and -0.93 days in generation 2, respectively. The realized
response in egg production to 280 days over 3 generations was 0.722%. The realized response in age at first egg
was found to decrease by -0.531 days over two generations of selection. These realized responses clearly
indicated the effectiveness of selection for improvement of economic traits (8-week body weight, age at first
egg and egg production to 280 days) in Indigenous Chicken of Bangladesh.