After the porcine epidemic diarrhea virus (PEDV) hit last year, pig farmers responded by growing their herds to make up for lost production. Big supplies hit the market, but consumers are picking them up, analysts said.

To be clear, having supplies to sell is important. But having too much drives prices lower, said Dave Struthers, a pig farmer and Story County Farm Bureau member in Collins. Struthers is president of the Iowa Pork Producers Association.

"Without...