The Influence of Epidermal Growth Factor on Maturation and Fertilisation of Bovine Oocytes In Vitro
The aim of the present study was to evaluate the efficiency of different doses of epidermal growth factor (EGF) on maturation and fertilisation of bovine oocytes in vitro. A total of 1209 high quality oocytes (follicles 2-8 mm in diameter, with unexpanded cumulus cells) were obtained by aspiration from ovaries collected at a slaughterhouse. The oocytes were then assigned into 6 groups: 1, 10, 100, and 1000 ng/ml EGF groups, as well as positive (EGF replaced with hCG) and negative (TCM 199 only, no supplement) control groups. Maturation and fertilisation rates were calculated at 39 °C in an atmosphere of 5% CO2 in air with maximum humidity for 24 and 20 h, respectively. Based on the cumulus expansion, no significant difference was found between the EGF groups. However, the highest dose of EGF (1000 ng/ml) had a lower percentage of 1st polar body extrusion than all other doses (P < 0.05). Considering monospermic fertilisation and non-fertilisation rates, a further significant difference (P < 0.05) was found between all the EGF groups. Moreover, there were also significant differences (P < 0.05) between the positive and negative control groups for all the parameters given. In conclusion, the data suggest that the EGF used as a media additive (more favourable at 100 ng/ml) on IVM can be useful for IVF of cattle oocytes.
The Influence of Epidermal Growth Factor on Maturation and Fertilisation of Bovine Oocytes In Vitro
The aim of the present study was to evaluate the efficiency of different doses of epidermal growth factor (EGF) on maturation and fertilisation of bovine oocytes in vitro. A total of 1209 high quality oocytes (follicles 2-8 mm in diameter, with unexpanded cumulus cells) were obtained by aspiration from ovaries collected at a slaughterhouse. The oocytes were then assigned into 6 groups: 1, 10, 100, and 1000 ng/ml EGF groups, as well as positive (EGF replaced with hCG) and negative (TCM 199 only, no supplement) control groups. Maturation and fertilisation rates were calculated at 39 °C in an atmosphere of 5% CO2 in air with maximum humidity for 24 and 20 h, respectively. Based on the cumulus expansion, no significant difference was found between the EGF groups. However, the highest dose of EGF (1000 ng/ml) had a lower percentage of 1st polar body extrusion than all other doses (P < 0.05). Considering monospermic fertilisation and non-fertilisation rates, a further significant difference (P < 0.05) was found between all the EGF groups. Moreover, there were also significant differences (P < 0.05) between the positive and negative control groups for all the parameters given. In conclusion, the data suggest that the EGF used as a media additive (more favourable at 100 ng/ml) on IVM can be useful for IVF of cattle oocytes.
___
- Leibfried-Rutledge, M.L., Critser, E.S., Eyestone, W.H., Northey, D.L., First, N.L.: Development potential of bovine oocytes matured in vitro or in vivo. Biol. Reprod., 1987; 36: 376-383.
- Im, K.S., Park, K.W.: Effects of epidermal growth factor on maturation, fertilization and development of bovine follicular oocytes. Theriogenology, 1995; 44: 209-216.
- Sanbuissho, A., Threlfall, W.R: The influence of serum and gonadotropins on in vitro maturation and fertilization of bovine oocytes. Theriogenology, 1990; 34: 341-348.
- Ocana, Q.J.M., Merlin, M.P., Ortega, M.M., Millan, M.M.: The effect of different sera and bovine serum albumin fraction (BSA) on in vitro maturation of immature bovine oocytes. Arch. Zootec., 1999; 48: 167-174.
- Abeydeera, L.R., Wang, W.H., Cantley, T.C., Rieke, A., Prather, R.S., Day, B.N.: Presence of epidermal growth factor during in vitro maturation of pig oocytes and embryo culture can modulate blastocyst development after in vitro fertilization. Mol. Reprod. Dev., 1998; 51: 395-401.
- Macun, H.C.: The effect of Follicle Stimulating Hormone and human Menopausal Gonadotrophin on in vitro maturation of bovine oocytes. PhD thesis (in Turkish). The Institute of Health Sciences, Ankara University, Ankara, TURKEY, 2004.
- Cetin, Y., Bastan, A.: Cryopreservation of immature bovine oocytes by vitrification in straws. Anim. Reprod. Sci., 2006; 92: 29-36.
- van Tol, H.T.A., van Eijk, M.J.T., Mummery, C.L., van den Hurk, R., Bevers, M.M.: Influence of FSH and hCG on the resumption of meiosis of bovine oocytes surrounded by cumulus cells connected to membrana granulosa. Mol. Reprod. Dev., 1996; 45: 218-224.
- Ocana, Q.J.M., Millan, M.M., Merlin, M.P., Ortega, M.M., Franganillo, A.R.: In vitro bovine embryos production: influence of serum and hormonal supplementation. Arch. Zootec., 1999; 48: 71-74.
- Izadyar, F., Zeinstra, E., Bevers, M.M.: Follicle stimulating hormone and growth hormone act differently on nuclear maturation while both enhance developmental competence of in vitro matured bovine oocytes. Mol. Reprod. Dev., 1998; 51: 339-345.
- Watson, A.J., De Sousa, P., Caveney, A., Barcroft, L.C., Natale, D., Urquhart, J., Westhusin, M.E.: Impact of bovine oocyte maturation media on oocyte transcript levels, blastocyst development, cell number, and apoptosis. Biol. Reprod., 2000; 62: 355-364.
- Landim-Alvarenga, F.C., Boyazoglu, S.E.A., Carvalho, L.R., Choi, Y.H., Squires, E.L., Seidel G.E. Jr: Effects of fetuin on zona pellucida hardening, fertilization and embryo development in cattle. Anim. Reprod. Sci., 2002; 71: 181-191.
- Sirard, M.A., Parrish, J.J., Ware, C.B., Leibfried-Rutledge, M.L., First, N.L.: The culture of bovine oocytes to obtain developmentally competent embryos. Biol. Reprod., 1988; 39: 546-552.
- Birler, S., Pabuccuoğlu, S., Alkan, S., Evecen, M., İleri, I.K.: Effects of different media alone or supplemented with hormones on in vitro fertilisation of cattle oocytes. İstanbul Üniv. Vet. Fak. Derg., 1997; 23: 511-516. (article in Turkish with an abstract in English)
- Zuelke, K.A., Brackett, B.G.: Luteinizing hormone enhanced in vitro maturation of bovine oocytes with and without protein supplementation. Biol. Reprod., 1990; 43: 784-787.