The objective of this study was to determine the effect on pregnancy outcome of either inseminating heifers twice (at 48 and 72 hours after withdrawal of a controlled internal drug release insert (CIDR) containing progesterone) or once (56 hours after CIDR withdrawal) following a seven-day CIDR synchronisation protocol. Dairy heifers (n=267) from five farms, with an age range of 388-736 days, w...

Our objective was to evaluate the effect of a progesterone-releasing intravaginal device (PRID) in 7-d Ovsynch protocol on pregnancy per artificial insemination (P/AI) and loss, compared with standard without progesterone supplementation. We hypothesized that supplementation during an would increase P/AI decrease loss. Data were collected lactating Holstein cows (n = 716) either received (contr...

Using a dispersed human luteal cell culture model, progesterone synthesis following treatment by incremental doses of human chorionic gonadotrophin (HCG) and the stable prostaglandin F2alpha (PGF2alpha) analogue cloprostenol, alone or in combination, was related to corpora lutea (CL) mRNA transcript abundance coding for the luteinizing hormone (LH)/HCG receptor (LH-R) and PGF2alpha-receptor (FP...

Este estudo teve como objetivo avaliar o comportamento sexual e a fertilidade de ovelhas borregas após aplicação um protocolo indução/sincronização estro utilizando GnRH. As fêmeas foram distribuídas aleatoriamente em dois grupos experimentais: grupo 1 (G1) foi constituído pluríparas com 2 3 anos idade, (G2) composto por borregas, 7 8 meses idade. Todas as submetidas ao Ovsynch, que consistiu n...