Some dogs were pregnant and giving birth as they were taken to shelters in Tucson, said Jenny Rose, a spokeswoman for the Humane Society of Southern Arizona. Ninety-six dogs were taken from the house Monday and another 700 on Wednesday, she said.
"The home was definitely in very bad condition, urine and feces all over the home, in the kitchen and bedroom, with a very strong odor," she said. "Obviously, 800 dogs in a triple-wide mobile home, they were packed in there. That being said, they were in pretty good shape."
The elderly owners, who have not been identified, were apparently overwhelmed but have cooperated with authorities, sheriff's Sgt. James Ogden said. No charges have been filed, but authorities continue to investigate.
The animals appeared to have had enough food, but a few were missing paws -- some from having been attacked by other animals, others apparently having caught their feet in fencing outside, Rose said.
The breeds included Chinese cresteds and Lhasa apsos. The owners were breeding and offering the dogs for sale, Rose said, but she described it as a hoarding case, in which elderly people sometimes feel no one else can give their animals a good home and won't part with them.
Deputies were alerted this month after a woman who bought a Chihuahua at the home reported the conditions, Ogden said. The dogs living inside the house apparently had free run of the premises, Ogden said. Others were found in other structures on the property.
Ogden described the living conditions as "horrible, filth everywhere ... probably one of the worst (situations) I've ever seen."
The animals will be offered for adoption soon, Rose said, adding that a rescue group from Phoenix had taken 100 of the dogs.