Genetic analysis of White Leghorn pure lines using RAPD-PCR and Immunocompetence

Three pure lines of White Leghorn, namely IWH, IWI and IWK are maintained at Project Directorate on Poultry, India along with a pedigreed random bred control population. The IWH and IWI were selected for part period egg number and IWK was selected for egg number initially and followed by feed efficiency. Molecular characterization was carried out through RAPD-PCR analysis of IWH, IWI, IWK and control populations. Humoral response to sheep RBC (SRBC) was evaluated in these populations to observe the immunocompetence. A total of 29 (out of 47) random primers (decamers) amplified the genomic DNA and generated bands in the size range of 108 to 5000 bp. The intrapopulation genetic similarity was highest in IWK (0.7591), followed by control (0.7534), IWH (0.7457) and IWI (0.7310), which indicated that more amount of genetic variation exists in IWH and IWI lines at molecular level and there is enough scope of selection in these two populations. The interpopulation genetic similarity between IWH and IWI was maximum among all the pair wise comparison which could be due to the fact that same selection criteria were used in these two populations. The interpopulation genetic similarity between IWH and IWK was lowest indicating that these two populations are wider at molecular level which is as per our expectation owing to the variable selection criteria followed in these two populations. The genetic distances between different pure lines varied marginally. The genetic distance between IWH and IWK was highest and between IWI and IWK was lowest. The Mean Average Percentage Difference (MAPD) between different groups varied between 56.16% (IWI and IWH) to 59.02% (IWK and IWH). The mean of the anti-SRBC titre in IWH, IWI, IWK and control population was 7.18, 6.46, 5.46 and 5.91, respectively. The heritability estimate of SRBC titre were moderate in pure lines and low in control population.