Two newborn clouded leopard cubs died Monday at Point Defiance Zoo & Aquarium, officials said Tuesday.
Necropsies did not show what the endangered cats died of but the cubs, who were never named, were born Saturday unusually small. The female weighed 4.5 ounces and the male weighed just over 7 ounces.
Veterinarians cared for the cubs around-the-clock since their mother did not produce milk and was not nursing them. according to the zoo.
Mother Jao Ying, 7, was brought from Thailand to augment genetics in clouded leopards at North American zoos. Their father was Chee Wit, 4.
“We have been trying to encourage this pair to breed for several years so this is a difficult loss,” zoo general curator Karen Goodrowe Beck said.
Although this breeding did not succeed, the zoo has seen past success with the endangered species. Five clouded leopards have been born and raised there since 2011.