Jackson, the 27-year-old, 11,000-pound bull elephant who lives at the Pittsburgh Zoo & PPG Aquarium, became a father again on Monday.

Donna, an elephant at Disney's Animal Kingdom, gave birth to a 233-pound female calf conceived two years ago with Jackson.

The calf is doing well, according to Disney officials. The new calf is the fourth of Jackson's offspring.

There is another female at Disney, and two in Pittsburgh: Victoria, a female born in 1999, and Callee, a male born in 2000.

Jackson is the only active naturally breeding bull African elephant in the United States, according to the Pittsburgh zoo.