"We think the pig model will fill an important gap," Li said. "In pigs, the pattern of neurodegeneration is almost the same as in humans, and there have been several treatments tested in mouse models that didn't translate to humans."

In addition, treatments for affected nervous system tissues could be better tested in pigs because their size is closer to that of humans, he said.

Li collaborated with his colleagues at Jinan University and the Chinese Academy of Sciences in Guangzhou, South China's Guangdong province. The pigs are now housed in Guangzhou.