Growth Modelling in Aseel Native Chicken

Abstract

Aseel, an important Indian native chicken breed, characterized by its aggressive behaviour, fighting ability and majestic gait is being utilized in India for developing crosses for backyard poultry farming. Therefore, information regarding its growth models is a prerequisite which is yet not available. So, present investigation is first of its kind in India which was carried out to evaluate various non-linear models and to find out the best fitting growth model in Aseel. Data on body weights from second week of age to 20 weeks of age at biweekly intervals were recorded on 1054 progenies from 30 sires and 139 dams hatched in three hatches and maintained at Desi Fowl Unit of Central Avian Research Institute, Izatnagar, Bareilly. Owing to the non-linear characteristic of growth, three non-linear models namely, Gompertz model, Bertalanffy model and Logistic model were evaluated. Goodness of fit for all the models were checked using coefficient of determination (R 2), adjusted coefficient of determination (Adj-R 2), Mean Square Error (MSE), Mean Absolute Error (MAE) and Akaike Information Criterion (AIC). The body weights at 0, 2, 4, 6, 8, 10, 12, 14, 16, 18 and 20 weeks of age averaged 28.18g, 65.94g, 138.99g, 237.06g, 359.95g, 533.74g, 718.28g, 922.33g, 1149.7g, 1321.65g and 1477.14g, respectively in males of Aseel native chicken. The corresponding body weights in females were 27.94g, 64.04g, 128.28g, 214.50g, 317.00g, 462.54g, 615.53g, 782.14g, 956.48g, 1077.65g and 1183.50g, respectively. Out of the three models, the Gompertz model, with R 2 = 1.000, Adj-R 2 = 1.000 and AIC = 29.839, best described the growth trend in males. In females, the Logistic model, with R 2 = 0.999, Adj-R 2 = 0.999 and AIC = 29.734 was found to be the best. In pooled or combined sex data, Gompertz model, having R 2 = 0.999, Adj-R 2 = 0.999 and AIC = 30.004, was determined as the best. The study revealed that these models can be used to determine the average body weights at any given point of time in Aseel native chicken under normal conditions. The investigation has generated baseline data on growth modelling and can also be used in other native chicken breeds.