Effect of insulin-like growth factor I and its interaction with gonadotropins on in vitro maturation and embryonic development, cell proliferation, and biosynthetic activity of cumulus-oocyte complexes and granulosa cells in buffalo.

In this study we have examined the effect of insulin like growth factor I (IGF-I) and its interaction with gonadotropins in the presence or absence of granulosa cell coculture on in vitro oocyte maturation (IVM) and their subsequent embryonic development in buffalo. We also have examined the role of IGF-I alone or in combination with gonadotropins on DNA synthesis, steroidogenesis, and protein synthesis of cumulus-oocytes complexes (COCs) and granulosa cells. Results showed that IGF-I stimulates oocytes maturation in a dose-dependent manner, with maximal effect at a dose of 100 ng/ml (P < 0.

Studies on glutathione S-transferases important for sperm function: evidence of catalytic activity-independent functions.

Our earlier studies reported the identification of a rat testicular protein of 24 kDa with significant similarity at the N-terminus with Mu class glutathione S-transferases (GSTs). Treatment of goat sperm with antisera against this protein identified immunoreactive sites on the spermatozoa and inhibited in vitro fertilization of goat oocytes by the antibody-treated sperm. The above observations indicated the presence of GST-like molecule(s) important for fertility related events on goat spermatozoa.

Comparison of various maturation treatments on in vitro maturation of goat oocytes and their early embryonic development and cell numbers.

In the present study, comparison of 2 different culture media (Ham's F-12 and M-199) for supporting in vitro maturation of goat oocytes, and their subsequent embryonic development was evaluated in the presence or absence of sera (estrous goat serum, EGS and fetal calf serum, FCS) and hormones (FSH, 0.5 ug/ml, LH, 5 ug/ml and estradiol, 1 ug/ml). Neither medium (Ham's F-12 or M-199) when supplemented with EGS and hormones showed any notable changes in the maturation rate nor in cleavage and blastocyst development.

Differential cleavage and developmental rates and their correlation with cell numbers and sex ratios in buffalo embryos generated in vitro.

In vitro matured and fertilized buffalo oocytes were co-cultured with buffalo oviductal epithelial cells (BOEC) in CRlaa medium. Cleaved embryos were separated according to the time of completion of first cleavage (i.e.

In vitro maturation of buffalo oocytes: role of insulin and its interaction with gonadotrophins.

A variety of signals is involved in the acquisition of competence to resume meiosis in buffalo oocytes. There is evidence that gonadotrophins are required for the resumption of meiosis and to achieve developmental competence. However, the source of the serum supplement also influences maturation of buffalo oocytes.