"For Fox Sake" has been created by Velocity Advertising and Maverick Media, and seeded through Digital Media Communications, the second time the agency has handled a campaign for IFAW.
The film, which is reminiscent of skits from the Channel 4 series 'Trigger Happy TV', shows the person dressed up in a fox costume running through the streets of London as a man dressed in full hunting regalia unleashes a pack of dogs behind him.
To a soundtrack that could have come from a 1970s cop show, the dogs chase the fox through the streets, finally cornering it and tearing off its arm. The dogs then look mystified, hand the arm back to the fox and walking, with the words "This does not happen in real life" appearing on the screen.
Photographs from real hunts then appear, showing dogs mauling foxes. The ad ends by urging viewers to click through to the , calling on them to write to their MPs in favour of a ban on fox hunting.
Phyllis Campbell-McRae, director of IFAW UK, said: "The government has made repeated assurances that its hunting bill will be reintroduced during the current parliamentary session, but the issue is yet to be resolved.
"Following our successful use of online viral marketing with DMC as part of our campaign to protect elephants from the ivory trade, we're launching this new viral initiative with the aim to get culture-driving, technology-savvy online users involved in widening awareness of the underlying issues and putting pressure on the government to reintroduce the hunting bill now."
The viral campaign is being seeded as "advertainment" content via DMC's online influencer network.
Justin Kirby, managing director of DMC, said: "IFAW is using our online viral seeding expertise again to maximise the spread of this powerful campaign. Our online film-tracking system will also provide accountability of the film's views and hotlinks in order to quantify the impact the viral campaign makes."
The viral ad can be watched .
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