Please have a look at Packy`s and Thonglow`s family tree at elephant.se:
Packy, an Asian elephant at Portland Zoo (Metro Washington Park Zoo)
And then tell me anyone REALLY thinks their genes are overrepresented. Yes, Thonglow had a lot of offspring, but most of them are dead, and right now, there is only a SINGLE elephant from the famous Portland line breeding: Rose-Tu, who has exactly one calf up til today, and the calf is still many years away from becoming fertile himself. There is no way in hell Thonglow`s/Packys genes are overrepresented. Hell, they are in grave danger of dying out!! Having a lot of offspring is worthless if the offspring themselves stop breeding. It`s what is carried into the second and third generation what counts. And on this front, the Portland genes are doing really poorly.
If you look at Thonglow`s 15 kids, only 3 are alive today, and the only one who culd breed again is Packy. If you look at Thonglow`s living grandkids, 2 are castrated bulls, 2 bulls never bred (Rama and Khun-Chorn), and female Sun-Surin is now 29 and way too old for a first calf. It won`t happen. Just Rose-Tu is there and breeding and a hope for the future.
Packy, Rama and Khun-Chorn (unless he is castrated too, I am not sure about that) should be moved elsewhere ASAP where they can breed naturally with young unrelated females. Khun-Chorn is obviously not going to breed in Springfield where is is now.
I have no idea why Packy and Rama, though genetically important AND fully mature bulls, are still living in Portland where their potential is totally wasted - in case of Packy, since decades. Packy is in no way too old for breeding, unless he has health issues the zoo has kept to themselves. For example, the Dickerson Park Zoo and the Rosamond Gifford Zoo both really need a fully mature bull. And the Lion Safari Park in Canada too, since they moved their breeding bull to Oklahoma.
The one thing I know is that if Asian elephants have no future in AZA zoos, mismanagement since decades is the main culprit.