Some of Hollywood's biggest stars are teaming up with the American Society for the Prevention of Cruelty to Animals to support a NY bill that would shut down what they say is a puppy mill pipeline funneling poorly-treated dogs into pet stores.
An ASPCA official tells TMZ ... thousands of pups are for sale in NY pet stores, and the dogs are shipped there from out-of-state breeders and middlemen, all of whom the ASPCA claims are running puppy mills.
Alec, Andy and Whitney fired off a letter in support of the Puppy Mill Pipeline Bill to NY lawmakers ... and it's also signed by Brooke Shields, Justin Theroux, Kristin Chenoweth, Sir Patrick Stewart and Edie Falco.
The bill, which would end the sale of puppies in pet stores once and for all, was passed by the NY Senate this month ... but it still needs to be approved by the State Assembly before landing on Gov. Andrew Cuomo's desk.