The goal of the giant panda ( Ailuropoda melanoleuca ) breeding program is to develop a self sustaining,genetically diverse population.Due to the common problems about sexual incompatibility and a limited number of captive born males that breed naturally,artificial insemination (AI) has become a critical genetic management tool.It is common practice,however,to combine natural mating and AI using semen from non breeding males.From 1998 to 2000 at the Wolong breeding facility,12 of 18 (66.7%) females produced 20 cubs following combined natural mating and AI.The objective of this study was to determine the efficiency of AI without natural breeding.In 1998 and 2000,seven females were anesthetized for transcervical AI on two consecutive days.Ejaculates from six males were collected by electroejaculation,diluted in an egg yolk diluent containing 0% or 4% glycerol and used either fresh or following cold storage at 4℃ (for 24 or 48 h) or cryopreservation using the pellet freezing method.Mean (±SEM) ejaculate traits in six male sperm donors were:ejaculate volume,3.3±0.5 ml;sperm concentration,1,429.8±235.4×10 6/ml;sperm motility,81.7±2.1%;progression (0～5,5=best),3.1±0.1;and normal sperm,79.3±9.2%.For AI (n = 14) in seven females,mean inseminate traits were:spermic volume inseminated,2.4±0.3 ml;sperm motility,73.5±2.9%;progression,2.5±0.1;and total motile sperm inseminated/AI,684.2±118.2×10 6.Four of seven (57.1%) females became pregnant and produced five cubs of which four survived.Mean gestation and litter size was 131.5±9.7 days and 1.3±0.3 cubs/litter,respectively.These results indicate that the efficiency of AI is sufficient for recovering valuable genes from non breeding individuals to enhance genetic diversity in the ex situ population of giant pandas.
