growth curve evaluation for indonesian indigenous red kedu chicken by using non-linear models

This study analyzed growth patterns in red kedu chickens using nonlinear models to assess their development over time and to identify the model which describe their growth best. in controlled conditions, 129 chickens (54 males and 75 females) were raised, and body weights were recorded weekly until 21 weeks of age. the models used for this study were gompertz, logistic, von bertalanffy and brody.  mean squared error (mse), akaike information criterion (aic), bayesian information criterion (bic), coefficient of determination (r2), and correlation coefficient (r) were used to assess the model fit. the gompertz model demonstrated the best fit for females, while the von bertalanffy model performed optimally for males. results revealed distinct growth dynamics between sexes. males consistently exhibited higher asymptotic weights (a) thus growth rates (c) become slower compared to females. asymptotic weight estimations ranged from 1,484.15±28.26 g (logistic) to 3,425.81±66.69 g (brody) for females and from 2,339.96±49.74 g (von bertalanffy) and 3,660.64±51.92 g (gompertz) for males, respectively. the weight at the inflection point (wi) was estimated from 494.22 g (von bertalanffy) to 742.01 g (logistic) and from 1,346.68 g (gompertz) to 1,473.80 g (von bertalanffy) for females and males, respectively. the gompertz model was the best for female chickens, while the von bertalanffy model performed best for males. the brody model had the worst performance in both sexes based on value of mse, aic, bic and r2