Comparison of different mathematical functions for fitting growth curves of ascitic and healthy broiler chickens

Ascites syndrome (AS) causes major economic losses in commercial meat-type chickens. The objectives of the current study were to select best non-linear growth curve functions (GCFs) ascitic and healthy chickens, investigate association ascites incidence with pattern. A total 5584 body weight (BW) records belonging 823 chickens (381 male 442 female) from a paternal pure Arian broiler line used. birds categorized into; female, female. Five GCFs including Logistic, Gompertz, Lopez, Richards, Von baretanalffy fitted BW all groups, separately. After estimation parameters for chicks individually, effect sex health status on assessed. results revealed that Richards function is groups. Comparison curves showed reach inflection point earlier than their counterparts (P<0.05). average rate rearing period was significantly higher (P<0.05), thereby suggesting there no direct relationship between rapid ascites. Therefore, genetic improvement used population both reduced may be possible utilization selection index might beneficial.