ABSTRACT
This study aimed to estimate microsatellite based genetic diversity in two lines [the selected RIRS and control line RIRC] of Rhode Island Red [RIR] chicken. Genomic DNA of 24 randomly selected birds maintained at Central Avian Research Institute [India] and 24 microsatellite markers were used. Microsatellite alleles were determined on 6% urea-PAGE, recorded using GelDoc system and the samples were genotyped. Nei's heterozygosity and Botstein's polymorphic information content [PIC] at each microsatellite locus were estimated. Wright's fixation indices and gene flow were estimated using POPGENE software. All the microsatellite loci were polymorphic and the estimated PIC ranged from 0.3648 [MCW0059] to 0.7819 [ADL0267] in RIRS and from 0.2392 [MCW0059] to 0.8620 [ADL0136] in RIRC. Most of the loci were highly informative [PIC>0.50] in the both lines, except for five loci in RIRS and six loci in RIRC line. Nei's heterozygosity per locus ranged from 0.4800 [MCW0059] to 0.8056 [ADL0267] in RIRS and from 0.2778 [MCW0059] to 0.875 [ADL0136] in RIRC. Out of 24 loci, 15 [62.5%] in RIRS and 14 loci [58.33%] in RIRC revealed moderate to high negative FIS index indicating heterozygote excess for these loci in corresponding lines, but the rest revealed positive FIS indicating heterozygosity deficiency. A mean FIS across the both lines indicated overall 10.77% heterozygosity deficit and a mean FIT indicated 17.19% inbreeding co-efficient favoring homozygosity over the two lines. The mean FST indicated that 10.18% of the microsatellite variation between the two lines was due to their genetic difference.