Embryo transfer in no cycling Crioula and Quarter horse breeds treated with estradiol cipionate and long-acting progesterone

• Main Authors: Fernanda Kaercher, Marlon Siqueira, Alessandro Mercadante, Tatiana Figueiredo, Romildo Romualdo Weiss, Felipe Siqueira, Luiz Ernandes Kozicki
• Format: Article
• Language: English
• Published: Instituto de Tecnologia do Paraná (Tecpar) 2011-12-01
• Series: Brazilian Archives of Biology and Technology
• Subjects: Embryo transfer; Cycling and no cycling mares; Long acting progesterone; Estradiol cipionate; Mares recipient
• Online Access: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000600009
• ISSN: 1516-8913; 1678-4324

The aim of this work was to prepare the mares for embryo transfer. In group 1 (G1,treated, n=15), recipient mares in anoestrus or in a transition period were treated with 5.0, 3.0 and 2.0 mg of estradiol cipionate at the days 0, 1 and 2 respectively, beginning at the day of ovulation (DO). From the fourth day on, the mares this group received long-acting progesterone weekly, up to the 120 day of gestation. At D8, the embryo was collected from the donor and transferred to the recipient. At D12, the ultrasonographyc diagnosis of pregnancy was carried out. The control group (G2, not treated, n=20) was formed by cycling recipient mares, displaying ovulation at each 2 to 3 days after the donors mare ovulation. The pregnancy rate was higher (p<0.05) in the mares from G2 (85.0%) than from G1 (53.3%). Thus, it could be concluded that the treated mares although showed lesser pregnancy rate than the cycling mare, were satisfactory alternative to be used mainly when there is no available cycling recipient.