مقايسه مدل هاي رشد هايپربولستيك با مدل هاي رشد كلاسيك در توصيف منحني رشد جوجه هاي نر گوشتي سويه راس

Hyperbolastic vs. Classic Model to Estimate Male Broiler Chicken Growth

Such classical growth models as Gompertz and Richards have been extensively used in broiler studies. This study was conducted to explore if 3 types of Hyperbolastic growth models known as HI (generalized from logistic growth model), H2 (stand alone) and H3 (generalized from Weibull growth model) may be empolyed to illustrate dynamic growth response of broilers and also how effective such models would be as compared with the classical growth models. A set of growth data were provided from 92 male broiler chicks reared from 1 to 56 days. Goodness of fit for individual growth model was determined using R2, MSE, RSD and Bias. The results of the present study indicate that, H3 could give a better fit (R2=0.99993) presumably due to its greater flexibility. In addition, H3 showed a higher accuracy and lower error (MSE= 264, RSD=16, Bias=0.5) than the other models, being followed by WeiBull, Gompertz, Richards H2 and HI growth models, respectively. In the meantime, Logistic growth model appeared with the lowest accuracy (0.99898) and a highest error (3432). A general evaluation in this study revealed that H3 can be considered as a useful tool to fit broiler growth dataset, with the highest accuracy and a lowest error than the other growth models.