Marc Metral, who has performed with pooch Wendy at the Moulin Rouge in France, left audiences stunned when the little dog appeared to mime on stage for his ventriloquy act.
However, while the pair won a standing ovation on the show, they have since been slammed by online by both viewers and animal rights charities.
One fan of the show took to Twitter in disgust over the act, writing: “Totally shocked at BGT putting a mask on an obviously terrified dog that’s not talent should be looked into for animal abuse.”
Another added: “I absolutely love dogs right but that singing dog on BGT is not what I’m about at all. Way too much.”
Still one more pointed out: “That dog was shaking the whole way through. I’m all for a laugh but the poor thing looked scared #BGT”
Responding to complaints, a spokesman for BGT said: “We take the welfare of all of our acts, including animals incredibly seriously.
“We consult at length with their owners and where necessary take third party advice.
“Marc has a huge amount of experience having worked with animals since 1980 and with Wendy for the last five years.”
However their statement has done little to alleviate those concerned, with a spokesman for the RSPCA announcing that the organisation will be contacting producers at Britain's Got Talent to investigate the matter further.
They said: "It is not clear if Miss Wendy was wearing any sort of muzzle or mask during the performance on Britain's Got Talent, however the RSPCA would be very concerned if it became clear that she was caused distress at any point.
"We will be contacting the show to ascertain what methods were used and how they impacted on the dog."
Simon Cowell, meanwhile, has always dismissed criticisms of having animals of the talent show, and said: “God no, I think the opposite! I think that we show animals’ personalities.
"I think they all have a great time on our show, you can actually see the dogs are wagging their tails and having the time of their life.”
What did you think of Marc Metral and Wendy’s performance - were you worried for the dog’s welfare?
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