"This group is doing particularly well and we will expect to transfer some of the langurs bred at the zoo to other zoos around the UK, " he said.

BBC: NEWS | UK | Northern Ireland | Zoo celebrates rare monkey birth

The stud-book keeper for the snow leopard, for example, is in Helsinki Zoo, and works closely with zoos in Russia, China, India and America.

ECONOMIST: From zoo cage to modern ark

Two of them remain at the zoo, while the other three have departed to zoos in France.

BBC: North African cheetahs born at Whipsnade Zoo

Evans said the Columbus Zoo in Ohio has been a global pioneer in taking gorilla babies in need of surrogates from other zoos, but this is a first for Cincinnati.

NPR: Grunting Ohio Zoo Workers Act As Moms To Gorilla