Although its bubble has burst, the building company constructing a new, high containment animal research facility at the National Animal Disease Center, 2300 Dayton Ave., called the incident a “happy coincidence.”

The huge construction balloon covering the site that regulated temperature for concrete pouring last winter was accidentally punctured by a crane Tuesday morning. Held up by three cranes, it was approximately 12 stories tall and longer than a football field.

“In the last two weeks, we were actually contemplating heavily bringing the bubble down,” said Mike Lenzen, corporate communications director for McCarthy Building Companies. “This kind of precipitated that.”

He said the bubble had outlived its usefulness because the temperature at the site does not need to be artificially regulated during the summer.

“It won’t be going back up,” Lenzen said. “It’s performed very well, it saved the project a lot of time and allowed us to work through the winter.”

Teresa Sutton, a spokeswoman for the National Animal Disease Center, said construction is planned to be completed sometime in 2007.

Lenzen said the bubble has been torn once before, during a windstorm.

High winds caused a tear in the bubble last December, allowing the air used to hold it up to escape.

Sutton said the building is part of a four-building project to conduct animal health research, including diagnostic research and the evaluation of commercial animal medicine.

A low containment facility for animals that are not carrying dangerous pathogens is in the design phase, with construction beginning next year, she said. Sutton said two lab buildings are also planned — the smaller one has already been built, and the largest is planned to begin at the end of the year.She said the biologics center functions as a “Food and Drug Administrationfor animals,” testing various commercial drugs and vaccines. The veterinary service labs will handle the diagnosis of animal pathogens and keep track of diagnoses made around the country.