LOS ANGELES — The inescapable Oscar night “selfie” of a cluster of Hollywood stars including Bradley Cooper, Ellen DeGeneres and Brad Pitt was already the most retweeted photo ever.Then a Dallas animal rescue group tweaked the tweet by Photoshopping in a mug of a mutt named Sandy. And the photo took on a new online life. The combination of a cuddly animal that needs a home and familiar faces is proving to be a publicity bonanza for Dallas Pets Alive, a small all-volunteer rescue group that started about 18 months ago.The campaign is called “muttbombing,” a play on the digital practice of photo-bombing, and the word has already been trademarked by Dallas Pets Alive, although it’s happy to share how to roll out a campaign with any rescue group that asks. Muttbombing was created by Dieste Inc., a marketing firm working pro bono for the rescue group, and launched Feb. 10. The group takes publicly posted Instagram photos — sometimes of glitterati, sometimes of ordinary folks — and uses Photoshop software to add the friendly face of rescued animals needing homes and attach often humorous captions urging adoptions.The Oscars selfie now has a caption reading, “I’m Sandy and I’m #muttbombing you in hopes of finding a home.”In another celebrity muttbomb, a pooch named Max sneaked in next to actor Ryan Gosling and asked, “Hey Ryan Gosling, can I follow you home? My parents always told me to follow my dreams.” Other photos have featured Kim Kardashian, Miley Cyrus and Jimmy Fallon. The goal of the publicity campaign — there have been 30 or 40 muttbombs so far — is to boost adoptions and reduce the number of animals euthanized by the Dallas pound, said Dallas Pets Alive Executive Director Leslie Sans. She runs the rescue operation from her house. The campaign increased traffic on the group’s Instagram page by 700 percent right away. The hashtag “muttbombing” also reached millions of Twitter users, Sans said. Ten dogs were placed in homes the first week of March, compared with just one during the same period last year. In 2013, Dallas Pets Alive found homes for 84 animals total. This year, it placed 40 in two months and seven days, Sans said. “In all my years, I’ve never had a campaign with 100 percent positive results,” said Carla Eboli, Dieste’s chief marketing officer. Dieste, with offices in New York and Dallas, has gotten calls from 10 animal shelters in the United States and one in the United Kingdom in the last few weeks, “saying they loved muttbombing and wanted to use it, and ‘How do you do it?’ ” Eboli said. One of the posts quickly got the attention of Hilary Walker, whose public Instagram picture was used in the campaign. But the Dallas interior designer and veteran blogger said the pooch muttbombing her was too big for her to adopt.“That dog wasn’t the right fit for us, but it motivated me and piqued my curiosity,” she said. She and her husband had already been thinking of getting a playmate for their other rescue dog. On the nonprofit’s website, Walker found a short-haired terrier mix named Marlon Brando, whom they met Saturday. “He will be a perfect fit for our house,” she said. Walker said she’s a big muttbombing fan. It got her to the website and now she has a new dog. Muttbombing has drawn the attention of officials at the Humane Society of North Texas, based in Fort Worth.Whitney Hanson, the organization’s new marketing director, said she had heard of the technique but didn’t know it was called “muttbombing.”“But I think that term is great,” she said. “It’s definitely something I’ve seen and something we’d consider doing. Anything we can do with social media that is viral and shared is always our goal.” Hanson said the Humane Society strives to “reach as many people as possible to increase awareness of an animal or adoptions in general.”Sans, the Dallas group’s executive director, said she doesn’t know how it will top muttbombs, but the plan is to start a Facebook campaign to recruit more foster volunteers. Dallas Pets Alive’s plan with muttbombing was to “hit every social media outlet we could,” Sans said. “The idea was to make noise.” It seems to have worked: DreamWorks Animation embraced muttbombing on Twitter and Facebook last week ahead of the premiere of Mr. Peabody & Sherman. The animated film, starring a genius dog, Mr. Peabody, and his adopted human son, Sherman, gave a boost to some homeless dogs in California by editing them into stills with the movie’s cartoon stars. A tweet said, “Wally & his friends are #muttbombing #MrPeabody & Sherman in hopes of finding a loving home!” It even got a shoutout from Dallas Pets Alive: “thanks for using #muttbombing! Best of luck with #MrPeabodyandSherman tomorrow! We all think it’s pawsome!” Staff writer Bill Miller contributed to this report.