Mathematical model for annual egg production curves of chicken

Seven growth models viz. exponential, monomolecular, Gompertz, logistic, Bertalanffy, Richards and modified logistic models, were used to study their performance in describing annual egg production curves of chickens. These models were fitted to the averages of 4-weekly cumulative total egg production from 20^th week to 72^nd week of age of two flocks of Indian native chickens viz. Kadakanath and Aseel. The output of Richards and Gompertz models was found same. On the basis of three measures of goodness of fit (MSE, MAE and AIC) the modified logistic model [N_t = a (1 + b exp(− ct) + d/t)⁻¹] which is suitable to describe body growth of chickens, was found best to describe the annual egg production curves of both the flocks.