Genetic Distance Between Divergent White Leghorn Chicken Lines After Three Generations of Selection for Humoral Response to Sheep Erythrocytes

Genetic analysis of immunocompetence and growth performance in a selected strain of Rhode Island Red chicken

“…It could be infered that the IC traits might be sex-independent, although, males had higher (P>0.05) estimates of antibody titre and serum lysozyme concentration than the females, while reverse trend was followed for serum IgG concentration in the present study. Similar findings were also reported in RIR (Das et al 2016a, Das et al 2015, Aseel (Kokate et al 2017), Kadaknath (Kokate et al 2017, Jaiswal et al 2014), and WLH chicken ( (Kokate et al 2017, Gupta et al 2010. The sex-component of variance was highly significant (P≤0.001) for the body weight estimates at different age groups with males being heavier than the females throughout the ages in the line of earlier reports (Das et al 2017, Eid et al 2010 indicating significant sex-differences and counter role of sex, a genetic factor to control the growth of body mass.…”

“…Similar magnitude of heritability estimates for body weights were also reported earlier (Das et al 2017, Qadri et al 2013. Moderate to high level of heritability estimates for different IC traits were earlier reported in RIR chicken (Das et al 2016a), Kadaknath (Jaiswal et al 2014) and low heritability in HSRBC line of White Leghorn (Gupta et al 2010). The present heritability estimates for serum IgG and body weights could indicate that effective improvement would be achieved using combined selection based on individual's own records and family performance for IC as well as growth parameters.…”

“…More serum IgG concentration also indicates birds' better general immune response against any antigen (Das et al 2016a). The present estimated least squares means of 5 dpi HA titre, serum lysozyme and serum IgG concentrations might be compared to the earlier reports in RIR chicken (Das et al 2016a, Das et al 2015, and divergently selected strains of White Leghorn for humoral response to SRBCs suspension (Gupta et al 2010). However, the present estimates were relatively lower than the reports in Aseel (Kokate et al 2017), Kadaknath (Kokate et al 2017, Jaiswal et al 2014 and White Leghorn chicken (Kokate et al 2017), but higher than the reports in different RIR crosses namely CARI-Debendra (Das et al 2014a) and CARI-Sonali (Das et al 2014b).…”

“…Poultry breeders have consistently being applying selection pressure on economic traits in high yielding populations which led to severe decline in immune response capabilities and increased susceptibility to numerous diseases (Tomar et al 2012). Indirect genetic selection for better IC traits provides an effective alternative approach because the progress per generation is cumulative, heritable, conserves natural resources and avoids repeated expenditure on medicines and vaccines (Gupta et al 2010). Therefore, the present investigation was carried out aiming at genetic analysis of RIR birds' IC and body weights after long term selection to generate information for chalking out future breeding programs for simultaneous improvement of production as well as protection status.…”

Investigating immunocompetence in Aseel, Kadaknath and White Leghorn chicken

“…The present estimated least squares means of HA antibody titre, serum lysozyme and serum IgG concentrations were relatively higher as evident when compared to the available reports in RIR chicken (Das et al 2014a(Das et al , 2015(Das et al , 2016, CARI-Debendra (Das et al 2014b), CARI-Sonali (Das et al 2014c), White Leghorn chicken lines (Gupta et al 2010), Dahlem Red chicken populations (Chatterjee et al 2007) and synthetic dam line of broiler chicken (Sivaraman et al 2005). The present HA titre estimates might be compared to the reports in RIR selected line (Das et al 2015(Das et al , 2016 and Aseel chicken (Kumar and Kumar 2011), whereas the estimates of serum lysozyme and serum IgG concentrations were in the higher line as reported in Aseel by Kumar and Kumar (2011).…”