Authors : Angela Gabriella D`Alessandro and Giovanni Martemucci
Abstract: The experiment was designed to evaluate ovarian response and embryo production in relation to multiple (4 vs 6 vs 8) and single injection treatment with FSH-p. Fifty dairy ewes were synchronized (FGA, in vaginal pessary, for 9 days + PGF2 , 50 ?g at 7th day) and subdivided into 5 superovulatory treatment groups: A) single FSH-p dose performed at the 24th h before pessary withdrawal (p.w.); B) single FSH-p dose at the 48th h before p.w.; C) 4 FSH-p doses, starting 24 h before p.w.; D) 6 FSH-p doses, starting 48 h before p.w.; E) 8 FSH-p doses, starting 60 h before p.w. until onset of estrus. All animals were treated with the same total dose of 250 IU FSH-p; Groups A) and B) were s.c. injected while Groups C), D) and E) were i.m. injected twice daily. Seven days after estrus, the ovarian response and embryo production were assessed. The results indicate that the increase in injections to 8 (Group E) does not improve superovulatory response, especially in comparison with the 6-dose regimen (Group D). The single dose treatment results in a similar ovarian response as the multiple injection regimen when performed at –24 h before p.w., but it decreases transferable embryo production when compared to Group D). Treatment D) induces a good ovarian response (8.8 ovulations/ ewe) and the highest number of transferable embryos (5/ ewe; 0.05>P<0.01).
Angela Gabriella D`Alessandro and Giovanni Martemucci , 2004. Efficiency of Superovulatory Treatment with FSH-p for In Vivo Embryo Production in Dairy Ewes: Multiple versus Single Dose Regimen . Journal of Animal and Veterinary Advances, 3: 388-393.