(CNN) The creator of the Labradoodle cross-breed has said he inadvertently unleashed a "Frankenstein('s) monster".

Wally Conron, 90, who worked for Guide Dogs Victoria in Australia when he bred the first Labrador-Poodle cross in 1989, spoke of his regrets at having begun a trend for designer breeds on an ABC podcast

"I opened a Pandora's box and released a Frankenstein('s) monster," he said.

His "big regret" is that his invention paved the way for "unethical, ruthless people" to breed the dogs without thinking of the health of their offspring.

According to Conron, the majority of Labradoodles are "either crazy or have an hereditary problem," with healthy examples of the breed "few and far between."

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