الفهرس 
AcknowledgementsOnly 14 pages are availabe for public view
 |  | from | 78 |  |  |
| | | from | 78 | | |
Abstract
The objectives of the present study were:
Frist study the effect of collection method on the oocytes quality.
Second investigate the effect of the season on the quality of bovine oocytes required for maturation.
Third, a comparative study was conducted between fresh and frozen semen used in the in vitro fertilization.
Fourth, a new design is used to increase the success rate in vitro fertilization.
Frist: Bovine were slaughtered over a period of 3 months, and the samples were transported to the laboratory within an hour after slaughter and produced 69 ovaries. The follicular fluid was aspirated through sterile 18- gauge needle attached to a 5 ml syringe containing a collection medium. The oocytes are collected and placed in petri dish and washed 3 to 5 times using the collection media. They were examined under a microscope to classify the oocytes.
The obtained experimental results are summarized as follow:
The aspiration technique significantly (P< 0.01) gave a high percentage of good quality oocyte in comparison to fair and denuded oocyte.
Second: Bovine were slaughtered and produced 452 ovaries. After oocytes aspiration, the oocytes are collected and placed in another petri dish. There is a media collection process is repeated three to five times washing the oocytes and removing any other cells present. After that, the oocytes are carefully examined and classified, which depends on the degree of homogeneity of the cytoplasm and the number of cells surrounding the oocyte. Grades A and B are selected and the oocytes are placed in the maturation media at each DROP containing ten oocytes. It is completely covered with paraffin oil and placed in the incubator at a temperature of 38°C and a concentration of CO2 5% for 18-22 hours to complete the maturation of the oocytes and examined under a microscope. The oocytes were considered mature when the first polar body was detected and cumulus cells expanded.
The obtained experimental results are summarized as follows:
The maturation was significantly higher during summer, autumn and winter (p<0.05). On the other hand, the maturation rate was significantly decreased during the spring (p<0.05).
Third: Bovine were slaughtered and produced 146 ovaries. After collection and maturation oocytes. Next day, the oocytes are checked to ensure their maturity and collected in a tube. For which vortex is made for 5-10 minutes to remove all the cumulus cells around the oocytes. And washed 3 times in the maturation media to ensure that it is clean and does not contain any cells of cumulus cells complex. It is also washed twice in the fertilization media. The fertilization media is placed in sterile dishes in the form of DROP 50µ and completely covered with paraffin oil, and at each point 10 oocytes are placed at most.
a. Fresh semen:
Semen is collected on the day of fertilization using an artificial vagina. The semen is evaluated for motility and concentration and then diluted for fertilization.
b. Frozen semen:
The semen straw is placed in a water bath at 37°C for 45-60 s to dissolve. The straw is wiped dry, the tip of the straw is cut off with scissors, and the contents of the straw are expelled into an eppendorf 2 ml tube.
The semen was mixed with a capacitation medium. The ratio of semen to medium should be 1:1 and put in the CO2 incubator for 45 minutes. Capacitated sperms are placed with mature oocytes and incubated at 39°C, 5% CO2.
The obtained experimental results are summarized as follows:
The morula rate increased significantly (p< 0.05) when fresh semen was used in comparison to frozen semen (54.52% vs. 38.02 %).
Fourth (new design): After collection, maturation oocytes and remove all the cumulus cells around the oocytes by vortex. The denuded oocytes are placed in the vacuoles in the slide filled with the fertilization medium. Through the channels, the semen (capacitated sperms) flows until it reaches all the vacuoles. The medium is easily changed twice a day by means of the tube attached to the slide.
The obtained experimental results are summarized as follows:
Using the slide saves time as the fertilization medium can be changed more than once a day. It also reduces the rate of loss that appears when using dishes.
When the micro fluid device used for in vitro fertilization increased of the plate, the morula rate was higher (70.7% vs. 54.52%).
The use of the micro fluid device also resulted in an oocyte hatching rate of 30%.