Abstract
This study was conducted to compare the heat stress response and production performance of chicks hatched in winter and summer. Among the 2,090 Korean native chickens examined, 1,156 hatched in winter and 934 hatched in summer. The amount of telomeric DNA, the expression of heat shock protein (HSP) genes, survival rate, egg production, and body weight were analyzed to evaluate the stress response and production performance of chickens. The results showed that the expression of HSP-70, HSP-90α, and HSP-90β genes in the winter-hatched chickens were significantly higher than those in the summer-hatched chickens during the growing and laying period (<italic>P</italic><0.05). There was no significant difference in the amount of telomeric DNA between summer- and winter-hatched chickens. The survival rate was significantly higher in the summer-hatched chickens than in the winter-hatched chickens at the laying period (<italic>P</italic><0.01). The hen-day egg production and egg weight in the summer-hatched chickens were also significantly higher than those in the winter-hatched chickens (<italic>P</italic><0.05). In contrast, age of sexual maturity of winter-hatched chickens was significantly earlier than that of summer-hatched chickens (<italic>P</italic><0.01). The body weights from birth to 24 weeks were significantly lighter in the summer-hatched chickens than in the winter-hatched chickens, however, it was reversed after 28 weeks (<italic>P</italic><0.05). In conclusion, the chicks hatched in the summer are more resistant to heat stress, with better productivity than the chicks hatched in the winter. These results suggest that the chicks grown at high temperatures have greater adaptability to the thermal environment.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
