Multiphasic analysis of egg production in Japanese quail.

A multiphasic function that considers egg production of individual hens to result from more than one phase was used to describe egg production for Japanese quail. Each phase is determined by number of eggs within a clutch, including internally laid eggs, and pause between clutches. Cumulative egg production was fitted by using a function (Koops and Grossman, 1992) expressing time in terms of cumulative egg number. Data from nine hens over a 31-day period were analyzed to estimate parameters for lag and delay. The data were preadjusted for internal laying. Lag ranged from -1.14 to .19 h. Unlike chickens, there was no clear relationship between lag and average clutch length in Japanese quail. Average delay was about 21.6 h and seemed to be longer than that in the chicken. Furthermore, the residual standard error for delay was higher in Japanese quail than in the chicken.