"The Safety Net for Pets" is a need-based group providing veterinary care in Denver. Mission statement (from their website): PetAid Colorado keeps pets and their people together by expanding access to quality veterinary care for those in need.
The Cartwright Foundation serves the greater Denver/Front Range, Colorado area and helps responsible pet owners with financial assistance for unanticipated medical or surgical costs for their pet(s) when it has been determined that without this assistance, the pet's life or well-being is in jeopardy. (From their website)
The Gabriel Foundation® is a 501(c)(3) avicultural and veterinary affiliated parrot welfare organization licensed by the state of Colorado, promoting educational outreach, conservation, rescue, rehabilitation, adoption, and sanctuary pertaining to the needs of parrots everywhere. (From their website)