Asian Pacific Journal of Reproduction

103-116

Authors: P. Perumal

Artificial insemination made a predominant contribution towards the improvement of genetic potential and increased productivity in animal husbandry sectors. In frozen semen technology, about 50% of sperm died because of cryoinjury or cryodamage during the process of cryopreservation and thawing of the semen. These cryo-damages can be minimized by use of various cryoprotective agents or cold shock absorbers in the frozen semen technology. Of which, egg yolk (EY) is most primarily important in the extender preparation for various mammalian species for longer period and it works against the cold shock during the cryopreservation process due to the presence of low density lipoproteins (LDL). Further, EY contains substances other than LDL that affect the sperm quality parameters especially reduced motility and inhibit the respiration of sperm; therefore, there was heavy demand on replacement of the EY with the particular responsible substances (LDL) in the semen extender. Later on, various investigators tried to extract the LDL from the EY of hen and finally succeeded to extract the LDL from the EY of hen for semen preservation of various species. The concentration of LDL used in various species is varied and this may be due to the composition and concentration of phospholipids, cholesterol and its proportion in the sperm membrane. In bovine species, the concentration of LDL was standardized as 8% (w/v) on dry matter basis. This is equal to 20% EY used in conventional semen extender. As it is explained that the 20% EY contains 68% LDL (13.6 g) and on dry matter basis, it is approximately 60% (8.16 g). This calculation indicates 20% EY contains 8% LDL on dry matter basis. The LDL protects the sperm by various mechanisms to maintain the integrity of sperm membrane, which is explained in the present review. It was concluded that the investigation is still to be carried out to find out the exact roles of apoproteins and lipids of LDL and to indentify and isolate the detrimental substances presented in the whole EY.

123-128

Authors: Mojtaba Rashedi, Ali Rooz Batavani, Reza Golam Najafi

Objective: To reveal the effects of 9-cis retinoic acid (RA) on cortical granules (CGs) migration and in vitro embryo production (IVP) rate in meiosis Ⅱ vitrified bovine oocyte. Methods: Following in vitro maturation (IVM) in a medium containing 5 nM of 9-cis-RA, 60 oocytes were vitrified and then thawed. Then, half of them were evaluated for CGs migration and the other half were used for in vitro fertilization and IVP (on day 3). In addition, the other 60 oocytes were considered as the control group, which did not receive RA in IVM medium. The data were presented to one way analysis of variance (ANOVA) and Duncan’s test. Results: Results showed that IVP rate (4-8 cells embryos) was significantly (P<0.05) higher than the control group when RA had been added to IVM medium. Furthermore, the presence of RA in IVM medium improved the rate and mode of CGs migration so that the rate of oocytes that had completed CGs migration in the group, which had received RA, was significantly higher than the control group. Conclusions: This study shows that presence of RA in IVM medium enhances the developmental competence and CGs distribution of meiosis Ⅱ vitrified bovine oocyte. Therefore, adding RA in IVM medium can decrease the ultrastructural changes during vitrification and can improve the efficiency of bovine oocyte vitrification.

136-138

Authors: Umie Lestari, Widodo, Sutiman Bambang Sumitro

Objective: To predict the protein similarity, biological function and structure of 116 kDa protein that was isolated from human sperm membrane of acrosome by using in silico. Methods: Predictions for 116 kDa protein similarity was done through comparative analysis of its isoelectric point (pI) and molecular weight to the UniProtKB/TrEMBL protein database. The three-dimensional structure of the protein was built using SWISS-MODEL. Results: The 116 kDa protein with pI 4.4 was expected to have similarities with CDH23 proteins that had pI 4.38, thus they likely had similar physical and biochemical properties. The predicted protein had an extracellular N-terminal that likely acted as a receptor, and showed cell recognition characteristic, playing a role in fertilization. Conclusions: The 116 kDa protein isolated from acrosome membrane has similarity on its biophysical character to the CDH23.

143-144

Authors: Maryam Eftekhar, Azam Agha-Rahimi, Mohammad Ali Khalili, Marjan Omidi

This paper is a case report on the success of oocyte retrieval and good quality embryo development following controlled ovarian hyperstimulation at early pregnancy. A 30-year-old patient underwent controlled ovarian hyperstimulation by gonadotropin-releasing hormone agonist long protocol. On the day of oocyte collection, a 5-week gestational sac was observed by exact sonography monitoring. However, via ultrasound guided follicle puncture, 7 oocytes were collected. After intarcytoplasmic sperm injection, 3 developed good quality embryos were cryopreserved. Moreover, the natural pregnancy was continued and finally a healthy live birth was achieved. Despite physiological hormonal changes during pregnancy, the follicular growth occurred and followed by oocyte retrieval and embryo development, subsequently.