. In the present experiment ,11 heads of giant male pandas ( /1瘤 凋 ρぬ melanoleuca )aged 6 to 20 years old males were used , During breeding season , semen collection was done with an interval of more than 7 days by means of an appropriate semen collection method and the collected semen was used for both artificial insemination and cryogenic storage , In freshly collected and stored semen , spermatozoa survived more than l30 h ( > 5days) at O -4℃ , while spermatozoa frozen for l to 6 years in

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... id nitrogen ( − 196℃ )maintained their motility for only 400 min ( > 6h)when incubated at 37℃ . These two types of semen samples also lead to the productめn of offspring following artificja [insemination , The giant panda spermatozoa were shown to have more than 30% of abnormal spermatozoa , higher than spermatozoa of other cat family . This brought about lower fertility after natural copulation or artiflcial insemination ,