Luteal Function and Follicular Growth Following Follicular Aspiration During the Peri-Luteolysis Period in Bos indicus and Crossbred Cattle

Autor(es)

Bisinotto, R. S. ; Ibiapina, B. T. ; Pontes, E. O. ; Bertan, C. M. ^[1] ; Satrapa, R. ^[2] ; Barros, C. M. ^[2] ; Binelli, M. ^[3]

Afiliação do(s) autor(es)

^[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

• Tipo de documento: Artigo Científico
• Fonte: REPRODUCTION IN DOMESTIC ANIMALS; v. 47, n. 2, p. 319-327, APR 2012.
• Citações Web of Science: 7

Resumo

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)

• Processo FAPESP: 05/51718-2 - Remocao mecanica de foliculos ovarianos:efeito na duracao da fase luteinica.
• Beneficiário: Bruna Trentinaro Ibiapina
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 02/08363-0 - Controle do desenvolvimento folicular e da ovulação para inseminação artificial, superovulação e transferência de embriões em tempo fixo
• Beneficiário: Ciro Moraes Barros
• Modalidade de apoio: Auxílio à Pesquisa - Temático
• Processo FAPESP: 05/51719-9 - Remocao mecanica de foliculos ovarianos: efeito na dinamica de crescimento folicular.
• Beneficiário: Rafael Sisconêto Bisinotto
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica