The aim of this studywasto evaluate the response of broiler breeder hens in terms of egg production to dietary nutrient intake. Using neural network (NN) models and breaking down the collected data from 98 breeder housesinto 3 wk intervals, 10 NN-based models were developed from 31 to 60 wk of age. The data lineswere divided into 2 random subsets of training (n=64) and testing (n=34) sets.The variables of interest for developing the models were metabolizable energy (ME; kcal/bird per day), and crude protein (CP), total sulphur amino acids (TSAA), lysine (Lys), calcium (Ca) and available phosphorus(AP), all g/bird per day. The random optimization algorithm was applied to the constructed models to find the optimal level of the input variables which maximized egg production during the different intervals. Thehigh R2 values in all developed models for both the training and testing sets indicate the accuracy of NN-based models in estimating egg production.The optimization results revealed that breeder hens consuming 485, 473, 471, 466, 460, 452, 448, 442, 437 and 445 kcal of ME/bird per day showed the highest egg production during 10 consecutive 3 wk intervals from31 to 60wk of age, respectively. Moreover, optimal performance of hens required intakes(g/bird per day) of the following values from 31 to 60 wk of age, respectively: CP: 25.3, 24.8, 24.4, 24, 23.6, 23.3, 22.8, 22.8, 22.7 and 23; TSAA: 1.1, 1.1, 1.08, 1.07, 1.03, 1.02, 1.01, 1.01, 1.01 and 1.03; Lys: 1.15, 1.11, 1.10, 1.09, 1.06, 1.05, 1.04, 1.04, 1.02 and 1.03; Ca: 5.3, 5.2, 5.1, 5.05, 4.9, 4.8, 4.7, 4.6, 4.66 and 4.8; and AP: 0.63, 0.6, 0.59, 0.58, 0.57, 0.56, 0.56, 0.55, 0.56 and 0.55.The results showed that the energy and other nutrient requirements of broiler breeder hens from 31 to 60 wk of age do not change in parallel with age. Moreover, it seems that company guideline recommendations mayunder-estimate the nutrient requirements of hens during these weeks when egg production is declininggradually.

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