| Full text | |
| Author(s): |
Bisinotto, R. S.
;
Ibiapina, B. T.
;
Pontes, E. O.
;
Bertan, C. M.
[1]
;
Satrapa, R.
[2]
;
Barros, C. M.
[2]
;
Binelli, M.
[3]
Total Authors: 7
|
| Affiliation: | [1] Sao Paulo State Univ Julio de Mesquita Filho, Coll Anim Sci, Dracena, SP - Brazil
[2] Sao Paulo State Univ Julio de Mesquita Filho, Inst Biosci, Botucatu, SP - Brazil
[3] Univ Sao Paulo, Dept Reprod Anim, Ctr Biotecnol Reprod Anim, Fac Med Vet & Zootecnia, Coll Vet Med & Anim Sci, BR-13635900 Pirassununga, SP - Brazil
Total Affiliations: 3
|
| Document type: | Journal article |
| Source: | REPRODUCTION IN DOMESTIC ANIMALS; v. 47, n. 2, p. 319-327, APR 2012. |
| Web of Science Citations: | 7 |
| Abstract | |
Follicular estradiol triggers luteolysis in cattle. Therefore, the control of follicle growth and steroidogenesis is expected to modulate luteal function and might be used as an anti-luteolytic strategy to improve embryo survival. Objectives were to evaluate follicular dynamics, plasma concentrations of estradiol and luteal lifespan in Bos indicus and crossbred cows subjected to sequential follicular aspirations. From D13 to D25 of a synchronized cycle (ovulation = D1), Nelore or crossbred, non-pregnant and non-lactating cows were submitted to daily ultrasound-guided aspiration of follicles >6 mm (n = 10) or to sham aspirations (n = 8). Diameter of the largest follicle on the day of luteolysis (7.4 +/- 1.0 vs 9.7 +/- 1.0 mm; mean +/- SEM), number of days in which follicles >6 mm were present (2.3 +/- 0.4 vs 4.6 +/- 0.5 days) and daily mean diameter of the largest follicle between D15 and D19 (6.4 +/- 0.2 vs 8.5 +/- 0.3 mm) were smaller (p < 0.01) in the aspirated group compared with the control group, respectively. Aspiration tended to reduce (p < 0.10) plasma estradiol concentrations between D18 and D20 (2.95 +/- 0.54 vs 4.30 +/- 0.55 pg/ml). The luteal lifespan was similar (p > 0.10) between the groups (19.6 +/- 0.4 days), whereas the oestrous cycle was longer (p < 0.01) in the aspirated group (31.4 +/- 1.2 vs 21.2 +/- 1.3 days). Hyperechogenic structures were present at the sites of aspiration and were associated with increase in concentration of progesterone between luteolysis and oestrus. It is concluded that follicular aspiration extended the oestrous cycle and decreased the average follicular diameter on the peri-luteolysis period but failed to delay luteolysis. (AU) | |
| FAPESP's process: | 02/08363-0 - Control of follicular development and ovulation for artifical insemination, superovulation and fixed-time transfer of embryos |
| Grantee: | Ciro Moraes Barros |
| Support Opportunities: | Research Projects - Thematic Grants |