Pittsburgh Zoo's 2 African elephants pregnant

The Pittsburgh Zoo & PPG Aquarium is gearing up to welcome two new occupants with the announcement that two of its three female African elephants are pregnant.

Photo: Pittsburgh Zoo's 2 African elephants pregnant

The births, if successful, will be the second for the 25-year-old pachyderms named Moja and Savanna. Jackson, the zoo's bull elephant, will be the father.

Both calves are expected in May or June 2008, zoo president Barbara Baker said.

Blood tests taken in November confirmed both elephants were pregnant. On Tuesday, zoo officials showed off ultrasound images of one of the babies, taken in January when Moja was about 14 weeks pregnant, reports AP.

Zoo officials said it was the first time the technology had been used on an elephant pregnancy. They plan to conduct monthly ultrasounds with the help of researchers from the Leibniz Institute for Zoo and Wildlife Research in Berlin.

The zoo also is doubling the size of its elephant house, with a new 80-foot-by-60-foot (25-meter-by-18-meter) addition that will have heated floors and plenty of room for the elephants. Visitors will be able to get nose-to-trunk with the animals through large viewing windows, officials said.