A new mathematical model of poultry egg production. Poultry So

ABSTRACT The compartmental model has been shown to be a suitable model for egg production based on physiological age of the hen. Assumptions made in developing the compartmental model are consistent with the physiology of egg production in poultry. However, when it is applied to egg production data from hen populations where the increasing slope of the egg production curve is jointly affected by the actual rate of change in the egg production and the variation in age at sexual maturity, the compartmental model cannot accurately characterize the change in the initial period of lay, due to limitations in its mathematical properties. In addition, the parameters for the initial age of egg laying and the rate of increase in egg laying no longer make reasonable biological sense. The new model derived in the present study incorporates a component of variation in sexual maturity, with two parameters defined in relation to the characteristics of sexual maturity in the flock. Thus the model will provide more information about the flock and can accurately characterize the whole period of lay. It may be reasonable to consider that the compartmental model and the modified compartmental model have respective suitable application areas and could complement each other. From a practical point of view, the modified compartmental model would have a wider application because it does not rely on synchronized egg production data which are of limited availability in practice. (Key words: egg production, modeling, compartmental model, sexual maturity