Comparison of ultrasound-guided vs laparoscopic transvaginal ovum pick-up (OPU) in simmental heifers.
Transvaginal ovum pick-up (OPU) offers several advantages over standard embryo transfer procedures. For a systematic comparison of the ultrasound-guided (U-OPU) and the laparoscopic OPU (L-OPU) method, groups of Simmental heifers were subjected to 1 of the 2 OPU-methods for 8 wk (15 sessions) followed by a treatment-free interval of 11 wk and then another 8-wk period of OPU using the alternative method. Parameters that were evaluated included the number of follicles aspirated, number and morphology of recovered cumulus-oocyte complexes (COCs), and developmental capacity of oocytes after in vitro maturation (IVM) and fertilization (IVF). Blood samples were also taken from the donors twice a wk for progesterone measurement. To evaluate effects of long-term OPU on subsequent fertility of donors, all heifers (n = 14) were inseminated during the first natural estrus after the OPU experiment. The proportion of Class I oocytes was significantly (P < 0.001) higher after U-OPU than after L-OPU (38.7% vs 21.0%). Following IVM/IVF, this difference in oocyte quality was reflected by the cleavage rate (U-OPU: 58.1%; L-OPU: 52.1%; P < 0.05) and the rate of development to morulae and blastocysts (U-OPU: 27.1%; L-OPU: 13.9%; P < 0.001). Among other factors, the greater changes in vacuum pressure during L-OPU vs U-OPU might be responsible for the difference in oocyte quality. This problem may be overcome by a more flexible system for regulating the vacuum. Progesterone levels were higher during the L-OPU than the U-OPU periods. Seven donors (50%) were diagnosed pregnant by ultrasonography on Day 28 and by palpation per rectum on Day 42.
Santl
B
B
Bavarian Research Center for Biology of Reproduction (BFZF), Oberschleissheim, Germany.
Wenigerkind
H
H
Schernthaner
W
W
Mödl
J
J
Stojkovic
M
M
Prelle
K
K
Holtz
W
W
Brem
G
G
Wolf
E
E
D000818:Animals; D002417:Cattle; D005260:Female; D005298:Fertility; D010535:Laparoscopy / Q000379:methods / Q000662:veterinary; D010063:Ovum / Q000000981:diagnostic imaging*; D011247:Pregnancy; D020858:Tissue and Organ Harvesting / Q000379:methods / Q000662:veterinary*; D014463:Ultrasonography