Abstract: 33

SEMEN CRYOPRESERVATION IN THE RHESUS MONKEY (Macaca mulatta).

W Si^{1 3} , XH Tang^{1 3} , XC He^{1 3} , P Zheng^{1 3} , WZ Ji^{1 3 *}, BD Bavister^{2 3 *}
Kunming Inst of Zoology, Chinese Academy of Sciences, Kunming, China ¹
Dept of Animal Health and Biomedical Sciences, Univ of Wisconsin, Madison, Wisconsin ²
China-US Primate Biology Laboratory, Kunming, China, and Madison, Wisconsin ³

Although semen cryopreservation has been successful in several species of non-human primate, there is no successful report in rhesus monkeys. This study compared two egg yolk extenders used successfully with cynomolgus monkeys (Macaca fascicularis) for cryopreservation of rhesus monkey semen: TEST (Tollner, 1990; 4.325% TES buffer, 1.0269% Tris buffer, 1 % dextrose, 3% glycerol and 30% egg yolk) and TTE (Sankai, 1994; 1.2% TES, 0.2% Tris, 2% lactose, 2% dextrose, 0.2% raffinose, 5% glycerol and 20% egg yolk). Sperm motility and in vitro fertilization ability were used to evaluate post-thaw sperm viability in 18 semen samples collected by electro-ejaculation from 4 adult male monkeys. Samples were diluted with non-glycerol TEST or TTE and equilibrated at 4°C then further diluted with equal volumes of TEST or TTE containing glycerol to reach final glycerol concentrations (3% and 5%, respectively), and frozen in 0.25ml in liquid nitrogen (LN₂) vapor for 10 min, finally placing them directly into LN₂. Semen was thawed by dropping straws directly into 37°C water for 2 min. Post-thaw sperm motility in TTE and TEST was 59% and 20%, respectively. After 2 h, 4 h, 8 h, 12 h and 14h post-thaw, sperm motility in TTE was 49%, 46%, 40%, 37% and 31%, respectively. Using sperm cryopreserved in TTE for insemination in vitro, 40% (8/20) of mature rhesus oocytes were fertilized and subsequently developed into morulae and blastocysts. Our results indicate that TTE is a good extender for rhesus semen cryopreservation, possibly due to the disaccharide which can maintain cell membrane stability during the freezing procedure. Supported by the MacArthur Foundation, NIH grant TW00840 (Fogarty International Center), and Yunnan Nature Science Foundation.

    This abstract is being presented on Sunday, August 1 at 8:00 AM to 10:15 AM at CUB 2nd Floor Ballroom.