Ultrasound-guided follicle aspiration and IVF in dairy cows treated with FSH after removal of the estrous cycle

Abstract

Recently, transvaginal ultrasound-guided follicle aspiration technolop has been found to be of great value for in 11i1ro fenilization _(IVF) programs, even though the oocyte recovery rate and cleavage rate of transferrable embryos were low. In this study, we investigated the effect of the removal of the dominant follicle at different stages of the estrous cycle on the ovarian response of donor cows. Four experiments (EXPs) were devised. In EXP I, 3 cows received 20 mg FSH on Day I, ovulation occurred on Day 0, and on Day 3 follicles were aspirated. In EXP 2, the dominant follicle of the first wave was removed on Day 6 from 3 cows which received 20 mg FSH on Day 7 and on Day 9 follicles were aspirated. In EXP 3, 2 pregnant cows received 20 mg FSH on 70 d of pregnancy and 48 hr later follicles were aspirated a total of 5 times at 5-day intervals. In EXP 4, after ovulation on Day 0, 9 cows received 20 mg FSH on Days 8 to 14 of the estrous cycle and 48 hr after the last injection, follicles were aspirated once. The respective mean± SO numbers of aspirated follicles and recovered oocytes were higher (p<O.OI) in EXP I (13.4 ± 1.7 and 8.7 :t 2.3), EXP 2 (12.1 ± 1.4 and 7.7 :t 1.7) and EXP 3 (10.7 ± 2.1 and 7.0 ± 2.2) than in EXP 4 (5.8 ± 2.3 and 3.1 ± 1.6). The oocyte recovery rates were higher (p<0.05) in EXP I, EXP 2 and EXP 3 than in EXP 4. Similarly, the respective numbers of viable oocytes and cleavqe rates were higher in EXP I, EXP 2 and EXP 3 (6.0 ± 1.3, S.O ± 1.1 and 4.6 ± I.S viable oocytes (p<O.OJ ); 66, 73 and 6S'l& cleava1e rates (p<O.OS)) than in EXP 4 (2.4 ± 1.1; .c6'lf>). The numbers of morulae and blastocysts were higher (p<O.OS) in EXP I, EXP 2 and EXP 3 than in EXP 4. In conclusion I) removal of the dominant follicles from lactating and pregnant cows enabled viable oocytes to be recovered constantly and repeatedly by aspiration at different reproductive stages, and that viable blastocysts can be produced after IVF. 2) The presence «absence of a dominant follicle significantly affects the ovarian responses to FSH treatment. 3) This ultrasound-guided procedure proved to be an effective, repeatable and safe method for viable oocyte recovery from valuable pregnant donors.I- KEY woaos: cattle, dominant follicle removal, follicle aspiration, oocyte, ultrasound.

Penelitian ini bertujuan untu melihat perkembangan embrio mencit tanpa pembiakan in vitro dan keberhasilan implantasi setelah dipindahkan ke rahim induk penerima. Embrio dipanen pada harike-4 (H-4) kebuntingan (H-1= hari saat sumbat vagina terlihat) dan zona pelusida dihilangkan dengan menggunakan pronase 0.25% selama 4-5 menit. Embrio dibiakkan dengan media biakan tissue culture medium 199 (TCM 199) yang diimbuhi albumin serum sapi (bovine serum albumin, BSA) 0.4% dalam inkubator CO2 5% pada suhu 37 derajat Celcius selama 5 jam. Tidak diperoleh perbedaan antara blastosis utuh (dengan zona pelusida) dan tanpa zona pelusida dalam perkembangannya menjadi blastosis ekspan, yaitu masing-masing 76& (31/41) dan 73& (43/59). Sebaliknya terdapat perbedaan morula utuh dan tanpa zona pelusida yang berkembang menjadi blastosis, yaitu masing0-masing 79% (49/62) dan 19% (10/52). Hasil pemindahan embrio menunjukan 48% (12/25) sari blastosis utuh dan 13% (6/45) dari blastosis tanpa zona pelusida yang dipindahkan berhasil mengalami implantasi dan 100% (3/3) induk penerima yang mendapatkan blastosis utuh serta 67% (4/6) induk penerima yang mendapatkan blastosis tanpa zona pelusida berhasil bunting pada pemeriksaan H-10 kebuntingan. Hasil ini menunjukan bahwa embrio tanpa zona pelusida mampu berkembang secara in vitro maupun in vivo.