Turning down the heat – How heat stress affects muscle growth and limits pork production

Turning down the heat – How heat stress affects muscle growth and limits pork production

Dr. Joshua Selsby

With the warm summer months in full swing, understanding what causes heat stress as well as how to prevent it is a crucial aspect for producers to consider across the state. On Iowa State University’s Swine Day, producers and industry professionals had the opportunity to further their knowledge in this area under the guidance of Dr. Joshua Selsby, ISU assistant professor of animal science.

“As our industry continues to advance in becoming more efficient, we select for hogs that have less resistance to heat stress,” Selsby stated in his opening remarks.

The main concern behind heat stress is that it leads to a degradation in muscle and less daily intake of feed leading to lower efficiency, which in turn negatively impacts pork production at multiple levels. Selsby informed producers that in order to prevent and eliminate as much heat stress as possible, it is first necessary to understand the affects that are taking place on a biological level.

Dr. Selsby gave a brief overview of the biological actions taking place while stating that a significant amount of energy is lost when an animal is under heat stress. When large amounts of energy drop, the body recognizes it and an automatic process will be stimulated to take place allowing for the removal of damaged cell particles. Selsby went on to state that with the proper removal of the damaged cell particles, the heat stress can be efficiently taken care. However, if the heat stress continues for multiple hours on end, proper autography doesn’t take place, which is where issues start to occur.

Determined to help educate producers on the causations and preventions of heat stress, Dr. Selsby and his team of research scientists have spent countless hours carrying out experiments that have a main goal of determining the different effects of heat stress on swine production. Producers were informed about one of Selsby’s studies that focused on the correlation between the severity of heat stress with the amount of time that passed. Selsby said that their results accurately distinguished that the hog’s body can automatically protect itself from the negative effects of heat stress by undergoing autophagy for the first six hours. After that, the body’s ability to cope with the stress declines and negative meat quality and poor efficiency starts to emerge.

As we look toward the future, Dr. Selsby announced that his team will continue undergoing studies focusing on skeletal muscle and heat stress to continue finding ways that will allow producers to implement further strategies and advancements that will lead to improved meat quality, well-being and production as a whole throughout the summer months.

If producers have further questions, Dr. Selsby is a great resource to get in contact with and his presentation slides can be found at https://www.ipic.iastate.edu/information/IowaSwineDay2017.html.