A new crime wave is sweeping the nation as much-loved pets catch the eye of thieves who see them as an easy cash grab.

Hundreds of cases of pet theft are reported to police every year, with thieves mostly eyeing off designer breeds that come with hefty price tags.

Crooks can fetch potentially thousands of dollars from just one dog, with the pooch often ending up in backyard puppy farms to breed more dogs.

Michelle Mullins's American Bulldog Bruno went missing over Christmas. (A Current Affair)

Bruno, an American Bulldog owned by the Mullins family, went missing from his home north of Bundaberg in Queensland on Christmas Day.

Owner Michelle was in Brisbane when she got a call from the pet sitter saying the dog had vanished.

She told A Current Affair their property was fully dog-fenced, that Bruno was wary of strangers and their other two dogs would not let a stranger into the yard.

Ms Mullins said Bruno would have to have been stolen. (A Current Affair)

She said she was worried the culprit could be known to the family.

Security footage shows the pet-sitter filling up the dogs' water bowl and bringing their beds onto the verandah.

A bit later on, something catches Bruno's eye from the top of the steps - it's the last time he's seen on camera.

Security footage shows Bruno's attention caught by something just before he runs off-camera. (A Current Affair)

Police have launched an investigation and there is a $2000 reward on offer.

"For anyone who knows anything, you have to give up, we are not going to give up," Ms Mullins said.

"So you have to step up, own what you have done, give our dog back."

Rochelle Hoenig's dog Sacchi disappeared from the family home in Sydney's west. (A Current Affair)

Rochelle Hoenig and her son Jamie have spent the past fortnight searching for their stolen American staffy, Sacchi.

He disappeared from their home in Sydney's west, and they believe he too was snatched.

"It's not fair that people can take someone's pet and a part of their family ... would they do that to a baby?" Ms Hoenig said.

There is a $1000 reward for Sacchi's safe return. (A Current Affair)

Sacchi was a companion dog for Jamie, who suffered a brain injury as a teenager.

"I miss him so much," Jamie said.

"He means everything to me, he means everything to everyone."

Sacchi was a companion dog for Rochelle's son Jamie. (A Current Affair)

There's now a $1000 reward for Sacchi's safe return.

Pet theft investigator Kirilly Cull said pet thieves should know they had "broken a family".