Location: Livestock Behavior Research
Project Number: 5020-32000-014-074-S
Project Type: Non-Assistance Cooperative Agreement
Start Date: Aug 21, 2023
End Date: Aug 20, 2024
The study objective is to evaluate the impact of genomic selection for improved heat tolerance on the immune response of pigs previously exposed to in utero heat stress.
Previous research by our group indicates that in utero heat stress causes immune system dysfunction in pigs which may have a negative impact on health and welfare. Therefore, it is expected that by improving the thermotolerance of gestating sows exposed to gestational heat stress, this negative offspring phenotype may be eliminated. Using their expertise in quantitative genetics, the Cooperator has developed a thermotolerance heritability index that has been integrated within a larger genomic selection index to genomically select sows and boars that have improved thermotolerance. At present, two generations of pigs have been generated using this selection index and ARS scientists have performed experiments to biologically validate the genetic selection methods. After breeding, selected sows considered to be more thermotolerant or thermosensitive based upon genomic selection will be exposed to either heat stress or thermoneutral conditions for the first half of gestation following previous methods by our group. Their offspring will then be subjected to postnatal immune challenges to evaluate the interactions between genomic selection for thermotolerance and in utero heat stress exposure on the immune response and physiological stress response of pigs.