Abstract
Heat stress negatively affects health and production in cows. Examining the cellular response to heat stress could reveal underlying protective molecular mechanisms associated with superior resilience and ultimately enable selection for more resilient cattle. This type of investigation is increasingly important as future predictions for the patterns of heat waves point to increases in frequency, severity, and duration. Cows identified as high immune responders based on High Immune Response technology (HIR) have lower disease occurrence compared to their average and low immune responder herd-mates. In this study, our goal was to identify epigenetic differences between high and low immune responder cows in response to heat stress. We examined genome-wide DNA methylation of blood mononuclear cells (BMCs) isolated from high and low cows, before and after in vitro heat stress. We identified differential methylation of promoter regions associated with a variety of biological processes including immune function, stress response, apoptosis, and cell signalling. The specific differentially methylated promoter regions differed between samples from high and low cows, and results revealed pathways associated with cellular protection during heat stress.
Highlights
Heat stress negatively affects health and production in cows
We identified significant differentially methylated promoters (DMPs) in blood mononuclear cells (BMCs) isolated from immune phenotyped Holstein dairy cows, identified as high or low immune responders, under both control and heat stress conditions
These results suggest that DNA methylation of promoter regions could contribute to variation in immune phenotypes in dairy cows, and variation in the response to heat stress
Summary
Heat stress negatively affects health and production in cows. Examining the cellular response to heat stress could reveal underlying protective molecular mechanisms associated with superior resilience and enable selection for more resilient cattle. Our goal was to identify epigenetic differences between high and low immune responder cows in response to heat stress. The specific differentially methylated promoter regions differed between samples from high and low cows, and results revealed pathways associated with cellular protection during heat stress. Cartwright et al.[32] recently demonstrated that BMCs from cows that were phenotyped as high immune responders based on their estimated breeding values (EBVs) produced more HSP70 and maintained cell proliferation better following heat stress treatment (4 h at 42 °C) compared to BMCs from cows phenotyped as average or low immune responders. High immune responder cows may have a superior response to heat stress and global warming compared with their average and low herd-mates
Sign-in/Register to view highlights & summary 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.
