Phenotypic Responses to Selection in Ross 308 Broiler Breeders: Long‐Term Growth Assessed With Nonlinear Models Across Four Generations

= 0.9974-0.999; MSE = 1521.5-1988.5; RMSE = 39.03-44.59), while the Richards model effectively captured sex- and generation-specific variation in growth trajectories. Inflection point weights ranged from 1819.5 to 2012.5 g in males and from 1433.7 to 1573.4 g in females. Predicted values were closely aligned with observed data across models, indicating good descriptive performance of the fitted functions. These findings highlight consistent phenotypic improvement in growth traits across generations and demonstrate that the Gompertz model provides a practical and robust framework for describing and monitoring growth dynamics in broiler breeder populations, supporting its use in selection and management decisions.