A quarterly publication of the Autism Research Institute

The Autism Research Review International is quarterly publication of the Autism Research Institute

Fall, 2017 | Number 4, Volume 31

Pig study: maternal infection can alter offspring’s sociability

More evidence that maternal infections during pregnancy can alter the behavior of offspring comes from a recent study of pigs. 

In the study, Adrienne Antonson and colleagues gave pregnant pigs a virus that causes flu-like symptoms and compared their offspring to the offspring of non-infected mothers. The researchers did not detect learning problems, memory problems, or altered immune responses in the offspring of infected mothers. However, these piglets behaved very differently in social tests, avoiding unfamiliar piglets while the piglets born to non-infected mothers preferred to visit them. 

The researchers suspected that maternal viral infection altered the piglets’ behavior by affecting immune cells in the brain called microglia during prenatal development. While these cells play an important role in brain development, altered microglia could attack healthy synapses or prevent new neurons from forming. 

Surprisingly, Johnson says, the piglets born to infected mothers did not display a change in microglial activity after birth. She adds, “If microglial cells are contributing to antisocial behavior, those changes are likely happening in utero. It’s possible microglia become activated during maternal immune activation, alter fetal brain development, and then return to normal before birth.” 

While previous studies investigating the effects of maternal infection on the behavior of offspring have primarily involved rodents, the researchers note that the brain anatomy, neurochemistry, and growth and development trajectories of pigs correspond more closely to those of humans in prenatal and early postnatal life.


“Maternal viral infection during pregnancy elicits anti-social behavior in neonatal piglet offspring independent of postnatal microglial cell activation,” Adrienne M. Antonson, Emily C. Radlowski, Marcus A. Lawson, Jennifer L. Rytych, and Rodney W. Johnson, Brain, Behavior, and Immunity, Vol. 59, 2017, 300-12. Address: Rodney W. Johnson, 227 Edward R. Madigan Laboratory, 1201 W. Gregory Drive, Urbana, IL 61801, [email protected]


“Infection in pregnant pigs leads to antisocial piglets,” news release, University of Illinois College of Agricultural, Consumer and Environmental Sciences, September 20, 2017.