Department of Animal Genetics and Breeding, College of Veterinary Science, Rajendranagar, Hyderabad-500 030 (A.P.).
* Corresponding author: e.mail - rmvjaya@gmail.com.
1 Department of AGB, College of Veterinary Science, Hyderabad.
Genetic parameters were estimated for growth, production and immune response traits in IWH strain of White Leghorn. The heritability values estimated from sire + dam component of variance indicated that the age at first egg and egg production were low to moderately heritable while body weights and egg weights at various ages were moderate to highly heritable. The heritability estimates for antibody response to SRBC injection, antibody response against New Castle disease virus (NDV) vaccine and cell mediated immune response to PHA-P injection were 0.374, 0.950 and 0.297 respectively. The genetic correlation of antibody response to SRBC injection with antibody titer against NDV vaccine was negative while the genetic and phenotypic correlation with cell mediated immune response to PHA-P was positive. The positive genetic association of both the measures of humoral immunity studied viz., antibody response to SRBC injection and NDV vaccine with age at first egg and body weight at 20, 40, 52 and 64 weeks of age suggested late maturity and good body weights at these ages in birds with good humoral immune response. The genetic correlation of antibody response against New Castle disease virus (NDV) vaccine with egg production upto 72 weeks of age was positive indicating that birds with good response to vaccines such as NDV may also have higher annual egg production. owevHThe high negative genetic correlation of immune response to PHA- P with age at first egg (−0.785) indicated early maturity in birds with good cell mediated immunity.
Body weight, egg production, immune response, genetic correlation, phenotypic correlation
