Nearly all the animals seized were pit bulls, an official with the Humane Society of Southern Arizona said.
Among those arrested was Mahlon Patrick, 63, whom investigators identified as one of the top dog fighting breeders in the country.
"We have dismantled a group of people at the upper echelon of dog fighting. This man has been involved for decades," said John Goodwin, a national Humane Society official, at a news conference.
It was not known whether Patrick had retained an attorney.
Most of the dogs were seized from a home in rural northwest Tucson, authorities said. About two dozen were removed from a mobile home property west of the Tucson Mountains.
Leads in the case were developed after Chicago police stopped a vehicle with several fighting dogs last March, and information eventually led to Tucson. Humane Society officials also provided information concerning the possibility of a dog fighting ring near Tucson.
About 10 of the dogs required medical attention. Authorities seized more than 50 weapons and training materials, as well as a device used to hold female dogs in place for breeding.
