Variation in the Transcripts Level of HSP70 and HSP90 in Fayoumi and Leghorn Chickens Breeds in Response to Acute Heat Stress

The variation in the environmental temperature will generally impose stress upon the organism, which may result in the evolution of adaptive genetic mechanisms to cope with temperature extremes in nature. This study aimed to estimate changes of HSF1, HSF3, HSP70 and HSP90 genes mRNA expression in stress-sensitive tissues of 2 chicken breeds (Fayoumi and Leghorn) during acute heat stress and chronic heat stress. The experiment was designed for 6 groups: control or thermoneutral group (TN), thermoneutral + acetic acid group (TN+AA), acute heat stress group (AHS), acute heat stress and acetic acid supplementation group (AHS+AA), chronic heat stress group (CHS) and chronic heat stress + acetic acid supplementation group (CHS+AA). Samples were collected from brain and liver to measure the transcriptional mRNA expression level of HSP70, HSP90β, HSF1 and HSF3. The results were revealed that Fayoumi chickens is more resistant to acute heat stress than Leghorn chickens through increasing expression of HSP70, HSP90β and HSF1 in brain and Liver tissues. Moreover, using acetic acid provides protection at time of heat stress. Fayoumi chickens is more resistant to acute heat stress than Leghorn chickens through increasing expression of HSP70 and HSP90β. acetic acid supplementation is more protective against acute heat