The Yangtze finless porpoise( Neophocaena asiaeorientalis asiaeorientalis) is a unique freshwater subspecies of N. asiaeorientalis,which is endemic to the Yangtze River of China and is now critically endangered. Due its natural habitat is not expected to improve in near future,ex situ conservation was considered as the most important strategy to prevent it from extinction. However,in theory,without effective human intervention,inbreeding is unavoidable for any ex situ small population. To evaluate the inbre...