Genetic analysis of body weights of Japanese quails (Coturnix japonica) in a semiarid area of Nigeria
Production and management of Japanese quail is relatively new in Nigeria but the birds have been attracting national attention in the recent times. This study on Japanese quail was conducted to estimate genetic parameters of egg production traits of Japanese quails in a semi-arid area of Nigeria. In a study that lasted for 40 weeks, 40 sires and 120 dams that produced 1267 progenies (743 females and 524) in three batches were used. The mixed model least squares and maximum likelihood programme of Harvey was used to estimate heritability, genetic, phenotypic and environmental correlations for body weights of Japanese quails from 0 – 40 weeks of age. Heritability estimates from sire, dam and, sire plus dam variance components from 0 to 36 weeks were low to moderate ranging from 0.071 to 0.569. Genetic correlations between body weights at the different ages were positive but varied widely from low (0.02) to high (0.977). However, the genetic relationships between body weights from hatch to 8 weeks were high (0.921 to 0.992). This may suggest that selection for final body weight may be based on early weight records. The phenotypic and environmental correlations were generally high, positive and ranged from 0.572 to 0.995 and 0.776 to 0.999, respectively. Though, the magnitude of genetic and phenotypic correlations of body weights decreased with increase in age of Japanese quails. Thus, rapid progress in selection for improvement of body weight of the Japanese quail may be.
Keywords: Heritability, genetic, phenotypic, environmental, correlations