When a 14-year-old terrier named Rascal was dropped off at the Nanaimo SPCA on Vancouver Island last week, it appeared as though the little dog was covered in dirt.

But when veterinarians took a closer look at the small dog, they realized that the “dirt” was actually masses of tiny fleas.

“The most fleas I’ve seen and I’ve been in practice for almost 40 years,” Ken Langelier, a veterinarian at the Island Veterinarian Hospital told CTV Vancouver Island on Tuesday.

With more than 100,000 fleas feasting on its blood, Rascal arrived at the Island Veterinarian Hospital in critical distress.

The terrier had already lost more than 85 per cent of its red blood cells and was on the verge of death.

The clinic’s staff said they were shocked when they rinsed Rascal and witnessed copper-coloured water dripping from the dog’s fur.

“When the fleas drink the blood and they go to the bathroom, they’re basically excreting digested blood,” Langelier said. “Basically you’re seeing a sea of blood.”

The Nanaimo SPCA gave the Island Veterinarian Hospital a choice: they could either euthanize the infested dog or give it an emergency blood transfusion.

The clinic staff chose the latter option.

“I looked at this dog and said, ‘You’re not dying on my watch, baby,’” said Langelier.

Luckily, one of the hospital’s employees owned a German shepherd named Katie that was a universal blood donor.

The dog was immediately brought to the clinic to provide blood for Rascal in a procedure that lasted four hours.

After receiving 400 millilitres of blood and countless baths, little Rascal finally regained its strength and was deemed flea-free.

The SPCA’s animal cruelty investigators said they’re now trying to find out where Rascal came from and who owned it.

“The dog came from the Nanaimo area, likely more the Lantzville area,” Tina Heary, special provincial constable for the BC SPCA, told CTV Vancouver Island on Tuesday.

Rascal likely suffered from flea bites for some time, Heary said. She called the case completely preventable.

“Flea infestations aren’t something just to take lightly,” she said.

If found, Rascal’s owner could face criminal charges.

On Tuesday, the small terrier was even given the opportunity to meet the dog that gave the life-saving transfusion. As the two dogs played, the clinic staff shared some more good news – Rascal is expected to make a full recovery.

Once fully recuperated, Rascal will be put up for adoption.

With a report from CTV Vancouver Island’s Jessica Lepp