Inheritance of body weight and rate of gain in Japanese quail.

The effects of hatch date, location and sex on the body weight and rate of gain in Coturnix coturnix japonica were examined. 2. The data conformed to a mixed and adjustments were made for the fixed effects sex, hatch date and location. Adjustment improved the precision of the estimates by reducing the error variances significantly. 3. Rearing equal numbers of birds from each family at different locations made the interactions negligible. 4. Weight gain was greater if illumination intensity up to 35 d was less. 5. Females were not heavier on the 1st day but were heavier on the 14th and 35th days than males. 6. Variance components and genetic parameters were estimated.