Just in time for Father’s Day, tests show that a bull elephant known as a prodigious stud has sired another offspring.

The Louisville Zoo said the tests showed Jackson was the father of Scotty, a male elephant recently born there. Scotty’s mother was artificially impregnated in 2005.

With six living offspring, the 28-year-old Jackson holds the record for fathering the most calves at U.S. zoos. He lives at the Pittsburgh Zoo, where zookeepers regularly collect Jackson’s semen and ship it around the country.

“He is extremely valuable,” said Deborah Olson, director of conservation and science programs at the Indianapolis Zoo and studbook keeper for African elephants in North America.

Jackson is by far the most productive of the five male African elephants available for breeding in North America; three others have two calves each.

“We really appreciate the (Pittsburgh) zoo’s willingness to use him for breeding,” Olson said. “They never say no, they’re just always right there ready to help.”

The zoo next year plans to mate Jackson with two elephants it is getting from the Philadelphia Zoo.