Carla Borck told KMGH-TV, Denver, they noticed something was amiss with Sophie, their 1-year-old basset hound, on Oct. 17.
"We noticed one evening that she started throwing up," Borck said. "She wouldn't lie down, and that's pretty out of character for her."
She took Sophie to an emergency veterinarian.
"They thought it was an upset stomach but they said, 'Let's do some X-rays for giggles.' When the X-rays came out it wasn't giggles. There were nails and other objects in her stomach," Borck said.
One of the nails had moved into the dog's intestines.
"The nails were old, rusted, sharp, jagged and rough and didn't look like it would feel very good to have them go down your throat," she said.
The vet removed 31 old roofing nails, the rabies tag and siding from the house.
The Borcks have puppy-proofed their home in case Sophie starts craving metal again.