
TY  - JOUR
A1  - Morton, K. M. 
A1  - Maxwell, W. M. C. 
A1  - Evans, G. 
T1  - 205. The effect of FSH concentration during IVM and gamete co-incubation length during IVF on the development of unstimulated prepubertal ewe oocytes
JF  - Reproduction, Fertility and Development
JO  - Reprod. Fertil. Dev.
Y1  - 2004
VL  - 16
IS  - 9
SP  - 205
EP  - 205
KW  - 
UR  - https://doi.org/10.1071/SRB04ABS205 
N2  - The developmental competence of prepubertal oocytes can be increased by the administration of gonadotrophins prior to oocyte collection (1)&#x003B; but this is not possible with abattoir-sourced oocytes, and modifications to the IVP system may increase in vitro development. Experiments were conducted to determine the effects of FSH concentration (10, 20 or 60 &#956;g mL-1) during IVM (5 replicates) and gamete co-incubation length (short: 2-3 h, long: 18-20 h) during IVF (6 replicates) on subsequent embryonic development. For both experiments ovaries were collected from prepubertal lambs (16-24 weeks) slaughtered at an abattoir and embryos produced in vitro (1). Data were analysed by chi-squared test. Oocyte cleavage at 48 hours post-insemination (hpi) was higher for oocytes matured in medium containing 20 (60/77&#x003B; 77.9%) and 60 (56/73&#x003B; 76.7%) than 10 &#956;g mL-1 (40/67&#x003B; 59.7%) FSH. Blastocyst formation (% cultured oocytes) on Day 7 (Day 0 = IVF) was higher for oocytes matured with 20 (31/77&semi; 40.3%) than 10 (16/67&#x003B; 23.9%) or 60 &#956;g mL-1 (20/73&#x003B; 27.4%). Oocyte cleavage at 48 hpi was reduced for short (36/57&#x003B; 63.2%) compared with long (49/55&#x003B; 89.1%) co-incubation, although blastocyst formation (% cultured oocytes&#x003B; Day 7) did not differ between groups (22/57&#x003B; 38.6% and 23/55&#x003B; 41.8%, respectively). These results demonstrate that increasing the FSH concentration above normal levels during IVM of prepubertal lamb oocytes improves development in vitro. Gamete co-incubation length did not influence the proportion of oocytes progressing to the blastocyst stage. (1) Morton et al. (2003) Proc. Soc. Reprod. Fert. P18. 
ER  -

