الفهرس 
IntroductionOnly 14 pages are availabe for public view
 |  | from | 109 |  |  |
| | | from | 109 | | |
Abstract
This study aimed to test and establish a standard method for cryopreservation of buffalo oocytes by vitrification, through investigating the effect of different equilibration times, different cryoprotectants concentrations and combinations, presence or absence of cumulus cells, and effect of different cryodevices Generally ovaries collected directly after slaughtering from local abattoir. Then oocytes transported to laboratory in thermo flask contain normal physiological saline. Oocytes aspirated from follicle (2-8 cm in diameter). Morphologically normal oocytes were selected, then equilibrated in equilibration solution .After a period of equilibration, oocytes transported to vitrification solution. Oocytes of all experiments were maintained in the vitrification solution (VS), for few seconds. During this time (few seconds), oocytes were loaded into different cryodevices (straw, OPS, or SSV). Then cryodevices plunged into LN. After a period of storage, oocytes warmed and subjected to assessment of quality using different methods (assessment of morphology, staining for viability, maturation rate, fertilization rate, and cleavage rate).In experiment 1 Equilibration for 10min. exhibited significantly higher %of morphologically normal oocytes, viability rate and maturation rate than that of 5 min. and 3 min. In experiment 2 this experiment demonstrated that 5% PROH resulted in the best quality vitrified-warmed oocytes which demonstrated by higher percent normal morphology, survival rate, and maturation rate. In experiment 3: 20% DMSO revealed significantly high survival and maturation rates (95.45% and52.38% respectively). In experiment 4, 40% EG revealed significantly high survival and maturation rates (89.79%, and54.55% respectively).In experiment 5 this experiment recorded that 40%EG +20% DMSO resulted in significantly higher survival and maturation rates (95.56%, and60.46% respectively) than other groups. In experiment 6. Showed that oocytes surrounded by a layer or more of cumulus cells had higher survival and maturation rates (96.00% and 97.5%) and (52.08 and56.41%) respectively than denuded ones. In experiment OPS and SSV techniques reported higher survival, maturation rates, and, fertilization rates (, and cleavage rate (20.93, than 0.25ml semen straw techniques.