DAVIE, Fla. -- An employee at a reptile store was in serious condition Wednesday after being bitten by a rattlesnake.

Mike Varonstrandt, the owner of Strictly Reptiles, located at 6450 Stirling Road, said the 37-year-old employee was cleaning the snake's cage and moving the reptile from one cage to another when he was bitten on the finger.

Surveillance video inside the store shows Tony Cruz getting bit by a snake. It then shows him pick up the western diamondback rattlesnake and put it back in a cage.

"He was cleaning the cage. He had his hand on a lid and just a little bit of his finger was exposed, but enough that this snake actually bit him," said co-worker Jeanne Brobsky.

Co-workers rushed Cruz to the emergency room at Memorial Hospital Pembroke, where Miami-Dade fire-rescue's anti-venom unit gave the man an antivenin treatment.

Cruz has worked with venomous snakes at the reptile wholesale store for the past three years, according to Brodsky. This was his first snake bite, she said. Co-workers said Cruz is licensed to work with venomous snakes. In the state of Florida, people who handle venomous snakes must obtain a license at a cost of $100, plus have $1,000 training hours working alongside someone with a license.

"Most rattlesnake bites cause major tissue destruction and a lot of swelling. It causes a lot of pain," said Al Cruz of the Miami-Dade response unit.

Wednesday was Tony Cruz's birthday, co-workers said. He is in serious condition in the intensive care unit, according to Local 10's Anjanette Flowers. He will likely be kept at the hospital for one or two days. He so far has received 18 vials of antivenin, according to Al Cruz.

"When you're dealing with venomous snakes, it's not a matter of if you're going to get bitten, it's when," Al Cruz told Local 10.