Honors Projects


Hannah Duffy


Commercial manufacturing and widespread use of polychlorinated biphenyl (PCB) in the United States has left lasting negative effects today. These persistent contaminants continue to bioaccumulate in the food web because of their stable structure, long half-life, and high lipophilicity. Adding PCB to the diet of Sprague-Dawley rats during pregnancy and lactation alters the thyroid status of offspring, and the behavior of the dams and pups. To determine a critical period or “window” of development with the greatest impact of PCB exposure of females on offspring fitness, female Sprague-Dawley rats were mated and fed PCB diet (25 ppm PCB 47 and PCB 77) during one of five, two week “development windows.” Ultrasonic vocalizations (USVs) were recorded on pup postnatal day (PND) 3, 7, 14, 21, and 22. Grooming behavior, open field behavior, and play behavior was also observed in pups. Blood serum was collected on PND 3, 7, 14, 21, and 22 for thyroid hormone analysis. Preliminary data show that there is a significant difference in the frequency of USVs emitted from pups among the window groups and also between developmental days PND 3 and 7. It is anticipated that those pups from dams given PCB diet early in gestation to early lactation will emit a significantly greater rate of isolation USVs, and show altered grooming, open field, and play behavior. Further behavioral testing as well as analysis of thyroid hormone status will likely demonstrate that PCB exposure during a particular “window” of development has the greatest impact on pup behavior.



First Advisor

Lee A. Meserve

First Advisor Department

Biological Sciences

Second Advisor

Howard C. Cromwell

Second Advisor Department


Publication Date

Fall 12-14-2013