پردیس کشاورزی و منابع طبیعی دانشگاه تهران Iranian Journal of animal Science 2008-4773 49 2 2018 08 23 Estimation of (co)Variance components of growth curve parameters in Japanese quail Estimation of (co)Variance components of growth curve parameters in Japanese quail 237 246 67841 10.22059/ijas.2018.250764.653609 FA Hadi Faraji Arough Assistant Professor of animal breeding and genetic, Research Center of Special Domestic Animals, University of Zabol, Zabol, Iran 0000-0002-7915-8200 Khadigeh Ebrahimi M.Sc. Student of Animal Breeding, Department of Animal Science Agriculture Faculty, University of Zabol, Zabol, Iran Gholam Reza Dashab Assistant Professor of Animal Breeding, Department of Animal Science Agriculture Faculty, University of Zabol, Zabol, Iran 0000-0003-2227-542X Mohammad Rokouei Associate Professor of Animal Breeding, Department of Animal Science Agriculture Faculty, University of Zabol, Zabol, Iran 0000-0002-8777-3561 Journal Article 2018 01 21 The purpose of the present study was to estimation of (co)variance components and genetic parameters of the growth curve in crossbred population. For this purpose, body weight records were fitted through the Gompertz curve and curve parameters were estimated. The final weight (Wf), hatch weight (W0), mature rate index (K), age (ti) and weight (Wi) in inflection point and growth rate in different days for all of the birds were predicted by Gompertz model. The estimated of (co)variance and genetic parameters were performed using a multi-trait animal model through Gibbs sampling. Heritability of the growth cure parameters including final weight, hatch weight, mature index and weight and age in inflection point was 0.335, 0.269, 0.273, 0.291 and 0.397, respectively. Also, the heritability of growth rate traits from hatch to 45 days was estimated high and varied between 0.311 to 0.424. The genetic correlation between hatch weight with mature index and final weight was positive (0.14 and 0.24), but the genetic correlation between hatch weight with age and weight at inflection point was negative (-0.24 and -0.12). The genetic correlation of the mature index with hatch weight, mature weight, age and weight at inflection point was negative. Genetic correlation of the mature index with growth rate in the early ages of bird was positive and it was estimated medium and negative for late. The weight at inflection point had the positive genetic correlation with most of growth rate traits and the change trend from beginning to end of growth period was ascending. The purpose of the present study was to estimation of (co)variance components and genetic parameters of the growth curve in crossbred population. For this purpose, body weight records were fitted through the Gompertz curve and curve parameters were estimated. The final weight (Wf), hatch weight (W0), mature rate index (K), age (ti) and weight (Wi) in inflection point and growth rate in different days for all of the birds were predicted by Gompertz model. The estimated of (co)variance and genetic parameters were performed using a multi-trait animal model through Gibbs sampling. Heritability of the growth cure parameters including final weight, hatch weight, mature index and weight and age in inflection point was 0.335, 0.269, 0.273, 0.291 and 0.397, respectively. Also, the heritability of growth rate traits from hatch to 45 days was estimated high and varied between 0.311 to 0.424. The genetic correlation between hatch weight with mature index and final weight was positive (0.14 and 0.24), but the genetic correlation between hatch weight with age and weight at inflection point was negative (-0.24 and -0.12). The genetic correlation of the mature index with hatch weight, mature weight, age and weight at inflection point was negative. Genetic correlation of the mature index with growth rate in the early ages of bird was positive and it was estimated medium and negative for late. The weight at inflection point had the positive genetic correlation with most of growth rate traits and the change trend from beginning to end of growth period was ascending. https://ijas.ut.ac.ir/article_67841_99791286d89586f31dd373ee15ae2265.pdf