[Edited Jan 27, 2022 to fix broken links etc.]
In my work in Toronto homeless shelters I’ve had the chance to put together a resource list for homeless pets, including free pet food, veterinary care, and fostering services for people fleeing domestic violence. The last one is particularly important, as evidence shows that violent abusers often use threats against pets as a method of threatening or preventing those who are abused from leaving the relationship. These resources are specific to Toronto, but check out the Ontario Veterinary Medical Association site for information on SafePet programs throughout Ontario.