Z-chromosome linked dinucleotide strs: association with reproduction traits in chicken

The study was conducted on 96 unrelated chickens belonging to three strains, namely, White Leghorn (PL2), Punjab Broiler (PB2) and Punjab Red (PR). Five pairs of Z-chromosome linked microsatellite loci (Ase50, MCWI54, HUR0404, HUR0411 and HUR0412) were studied in the selected strains with an aim to genetically characterize the divergent stocks and to associate the polymorphism with growth and production traits. The microsatellite band patterns were resolved using 3.5% metaphore agarose gel at 80–100 volts. The number of alleles in the microsatellite loci varied from 8 to 10 among the different germplasms, indicating high degree of polymorphism across the three breeds. Locus HUR0412 had the maximum number of alleles (10), thus it is the most polymorphic among all the loci under study. The allele ‘I’ of the locus HUR0412 is the candidate private allele that could be used to characterize PL2 breed. Except for the HUR0412 locus no other loci could be characterised for harbouring strain specific private allele. The PIC value was the highest in loci as Ase50 in PL2 (0.115), MCW154 in PR (0.139) and PB2 (0.821). The HUR0412 locus exhibited significant difference among different genotypes of layer (PL2 and PR) females for the traits like, body weight at 40 weeks of age (BWT40), egg no. at 40 weeks (EN040), age of sexual maturity (ASM) and rate of lay. The performance trait, egg mass (EMASS) was significantly different (P<0.05) among the genotypes of layers for the locus MCWI54. The Chi-square test for various loci and breeds were significant i.e. the population were not in Hardy-Weinberg equilibrium.