Abstract The aim of this study was to investigate the effect Lactobacillus reuteri E81 (LRE) probiotic supplementation on heat stress responses in chukar partridges ( Alectoris chukar). birds were divided into two groups, one which exposed (HS). Within each group, four subgroups, including 64 birds, created for three treatment doses (200, 400 or 600 mg/kg) LRE and control. experiment started wi...