ASPCA

One of the most well known, and probably the most famous animal organizations in the U.S. is the ASPCA, or the American Society for the Prevention of Cruelty to Animals. This is a non-profit organization, that is dedicated to preventing cruelty towards animals and informing the public of the inportance of spaying/neutering, and properly caring for all animals.
This organization was started on April 10, 1866, by Henry Bergh. On his way to America, was the first time Bergh took action against the cruelty towards animals. In London, he took notes on Earl of Harrowby, president of England's Royal Society for the Prevention of Cruelty to Animals.
Because of him, about nine days later an anti-cruelty law was passed, and the ASPCA was granted the right to enforce the law.
Although the ASPCA originally focused mainly on horses and livestock, it has spread to focusing on all other animlas as well. Since it was first started, the ASPCA has been very successful in educating the public on the proper ways of caring for all animals, as well as traing all types of animals. They have also been successful in preventing cruelty to animals, by informing people about the horrors of dog fighting, puppy mills, dog racing, animal neglect, and more. It is definitely safe to say that the ASPCA will be here for a long time, defending all animals.
For more information about the ASPCA, visit their site: http://www.aspca.org/