الفهرس 
Introduction
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Abstract
Dromedary camel ovaries were collected from slaughterhouse and oocytes were recovered by aspiration from all visible follicles on the ovarian surface with 2-8 mm in diameter. After collection, oocytes were counted, evaluated and classified. Only morphologically high quality immature oocytes were vitrified using one or two steps procedures with different exposure times to cryoprotectants (30, 60 and 90 sec) and thawing at 15 or 20oC. Then, vitrified oocytes were in vitro matured compared with fresh oocytes. Oocyte yield was recorded and the number of oocytes/ovary was calculated. Oocyte recovery rate (RR) was determined as percentage of the total vesicular follicles. Results revealed that average number of recovered oocytes per ovary was 8.06, and recovery rate was 76.6%, being the highest for compact oocytes (39.2%). Post-thaw survival rate of total oocytes and those in normal type was higher and those in abnormal type was lower with two than one step(s) procedure (91.2, 86.0 and 5.2% vs. 80.0, 68.1 and 11.9%). Post-thaw survival rate of normal oocytes was higher (P<0.05) and that of abnormal oocytes was lower (P<0.05) with 90 (80.9 and 6.8%) than 30 (71.5 and 10.7%) and 60 (78.8 and 8.1%) sec exposure time, respectively. Post-thaw survival rate of normal oocytes was higher (P<0.01) and abnormal oocytes was lower (P<0.001) with 20 (79.8 and 6.9%) than 15oC (74.3 and 10.2%), respectively. Frequency distribution of oocytes at M II stage was higher (61.7 and 36.6%), while that of degenerated (12.1 and 21.3%) and immature oocytes (4.0 and 8.5%) was lower (P<0.05) for fresh than vitrified oocytes, respectively. In conclusion, camel oocytes could be cryopreserved by vitrification using two steps and exposure time to cryoprotectants of 90 sec procedures and gave the highest viability at thawing temperature of 20oC. However, low maturation rate (36.6%) was obtained when vitrified oocytes (under these conditions) were in vitro matured.