Hsp90, hsp60 and hsf‐1 genes expression in muscle, heart and brain of thermal manipulated chicken (539.12)

Abstract

The aim of this study was to investigate the effect of thermal manipulation (TM during embryonic days ED12 ‐ 18) on the gene expressions of Hsp90 and Hsp60 and HSF‐1 on hatchability, growth performance and thermotolerance acquisition during thermal challenge (TC) in three different thermal manipulated groups and also to investigate their ability to cope with thermal challenged (TC) during post hatching days (10 and 28) by using real time RT‐PCR and ELISA techniques. One thousand five hundred fertile chicken eggs were divided randomly into four groups: control group (37.8°C), TM1 (39°C for 9h), TM2 (39°C for 12h) and TM3 (39°C for 18h). Chicks from each treatment group were then randomly divided into 2 sub‐treatment groups (Naive and TC). Chicks in TC groups were subjected to thermal challenge at 43.0°C for 6h on days 10 and 28 of age while naïve chicks were kept under regular conditions. Chick’s response to TC was evaluated by determination of body temperature, plasma T3 and T4 levels and mRNA levels of Hsp90, Hsp60 & Hsf‐1 of muscle, heart and brain. There was a significant differences in muscle, heart and brain mRNA levels of Hsp90, Hsp60 & Hsf‐1 during embryogenesis and during TC in post‐hatch chicks that indicates tissue responds differently to heat stress. While hatchability was adversely affected, the body weight in TM3 chicks was significantly higher at the end of the study period (35 days). Results of this study indicated a long‐term enhancement of Hsp90, Hsp60 & Hsf‐1 gene expressions associated with thermotolerance acquisition in treated chicks without adversely affecting body parameters.