The SPCA was called by the Monterey Police Department at about 1 a.m. to help rescue the 17 cats, 24 dogs and 7 puppies that were being kept in unsanitary conditions, SPCA spokeswoman Beth Brookhouser said in an email.
The rescued pets were suffering from flea infestations, eye infections, dental infections, and malnutrition.
Many of the dogs were covered in matted fur, Brookhouser said, and the house where the animals were being kept was nearly three feet deep in garbage and animal waste.
The house has since been declared uninhabitable, she said. There was no immediate information on the owner.
The SPCA is asking for help feeding and treating the rescued animals.
Donations can be made online at www.spcamc.org, or by calling the shelter directly at (831) 373-2631.