Turkeys on a fourth farm have tested positive for avian flu.
The positive tests have led to the euthanization of another 15,200 turkeys, according to the Indiana Board of Animal Health.
The farm is in Greene County, which is north of where the flu was first detected, about two weeks ago in Dubois County.
Since then about 115,000 birds have been killed to prevent the flu from spreading.
Another 13 farms are now under quarantine.