پردیس کشاورزی و منابع طبیعی دانشگاه تهران Iranian Journal of animal Science 2008-4773 48 4 2018 02 20 Estimates of genetics parameters of egg weight and body weight due to social interaction in a commercial broiler chicken line Estimates of genetics parameters of egg weight and body weight due to social interaction in a commercial broiler chicken line 585 592 65831 10.22059/ijas.2018.248678.653598 FA Vahid Arab-Firozjaie M.Sc. Student, Department of Animal and poultry science, Aburaihan Campus, University of Tehran, Iran Rostam Abdollahi Arpanahi Assistant Professor, Department of Animal and poultry science, Aburaihan Campus, University of Tehran, Iran Abdolreza Salehi Associate Professor, Department of Animal and poultry science, Aburaihan Campus, University of Tehran, Iran Journal Article 2017 12 26 Social interaction among individuals can have important influences on the production and fitness traits in livestock population. Therefore, the aim of this study was to estimate variance components due to social effects for two production traits including egg weight and body weight in a commercial broiler chicken line. In this study 29,645 production records provided by Arian commercial broiler chicken line center of Iran were used. Data were collected during years 2007 to 2016 and analyzed with four different single-trait animal models including or excluding random genetic social and pen effects, using AI-REML algorithm. For each trait, the most appropriate model was chosen based on Akaike information criteria. Based on the most appropriate fitted models, direct heritability estimates ranged from 0.60±0.02 (egg weight) to 0.55±0.02 (body weight). Even though social genetic variance was small, it was significantly different from zero for body weight and egg weight. The variance due to random pen effect was significant for egg production traits. In general, social genetic and pen effects were important effects regardless of trait under study. Correlation between direct and social genetic effects was negative (-0.51) for egg weight and positive (0.27) for body weight. In general, we concluded that social genetic and pen effects should be included in the statistical models for genetic evaluation of egg weight and body weight in broiler chicken. Social interaction among individuals can have important influences on the production and fitness traits in livestock population. Therefore, the aim of this study was to estimate variance components due to social effects for two production traits including egg weight and body weight in a commercial broiler chicken line. In this study 29,645 production records provided by Arian commercial broiler chicken line center of Iran were used. Data were collected during years 2007 to 2016 and analyzed with four different single-trait animal models including or excluding random genetic social and pen effects, using AI-REML algorithm. For each trait, the most appropriate model was chosen based on Akaike information criteria. Based on the most appropriate fitted models, direct heritability estimates ranged from 0.60±0.02 (egg weight) to 0.55±0.02 (body weight). Even though social genetic variance was small, it was significantly different from zero for body weight and egg weight. The variance due to random pen effect was significant for egg production traits. In general, social genetic and pen effects were important effects regardless of trait under study. Correlation between direct and social genetic effects was negative (-0.51) for egg weight and positive (0.27) for body weight. In general, we concluded that social genetic and pen effects should be included in the statistical models for genetic evaluation of egg weight and body weight in broiler chicken. https://ijas.ut.ac.ir/article_65831_e613910b60d4650d699328f3b870d5bb.pdf