Indian Journal of Poultry Science

Lines for response to sheep RBCs were produced through divergent selection in a base population of synthetic dam line (SDL) maintained at experimental broiler farm of the institute. In each generation 8 sires were randomly allotted to 6–8 dams in a full-sib mating plan. In F₂ generation the mean response titer [log₂ (n+1)] to sheep RBC in high responding line (HSRBC) was 8.359±0.221 and in low responding line (LSRBC) was 6.220±0.234. Genetic divergence between HSRBC and LSRBC line pooled DNA samples (pooled over 10 extreme responders per line) of second-generation individuals was estimated using RAPD-PCR analysis. The mean antibody titer [log₂(n+1)] of sheep RBC in selected individuals in HSRBC lines was 12.001 and that in LSRBC line was 2.192. A total of 20 random primers (decamer) were screened, out of which 15 primers amplified the genomic DNA. Only, ten primers generated reproducible and polymorphic RAPD profiles, generating 287 to 2010 bp bands and were used for further analysis. Out of total 95 bands amplified, 53 (55.07%) were polymorphic. The number of polymorphic loci ranged from 3 to 8 with an average of 5.3. Band sharing frequency ranged from 0.18 to 0.80 with an average estimate over 10 primers as 0.58. The genetic distance between HSRBC and LSRBC as estimated by RAPDistance software version 1.04 was 0.388.