G. Sa Filho1, R. L. Valarelli2, and J. L. M. Vasconcelos1, 1FMVZ - UNESP, Botucatu, Brazil, 2Pfizer Animal Health, Brazil.
Effect of treatment with melengestrol acetate combined with estradiol cypionate on pregnancy rates along a 70 days breeding season in postpartum Nellore cows. R. F. G. Peres*1, O. G. Sa Filho1, R. L. Valarelli2, and J. L. M. Vasconcelos1, 1FMVZ - UNESP, Botucatu, Brazil, 2Pfizer Animal Health, Brazil.
Effect of estradiol cypionate dosage (1 vs. 2 mg) on estrus detection and pregnancy rates of postpartum Nellore cows synchronized with melengestrol acetate. R. L. Valarelli*1, O. G. Sa Filho2, and J. L. M. Vasconcelos2, 1Pfizer Animal Health, Brazil, 2FMVZ - UNESP, Botucatu, Brazil.
Pregnancy rates in a 10 days breeding season in postpartum Nellore cows treated with melengestrol acetate associated or not with estradiol cypionate. R. L. Valarelli*1, O. G. Sa Filho2, M. Meneghetti2, and J. L. M. Vasconcelos2, 1Pfizer Animal Health, Brazil, 2FMVZ - UNESP, Botucatu, Brazil.
Fixed-time artificial insemination in replacement beef heifers after treatment with human chorionic gonadotropin (hCG), progesterone, and prostaglandin F2α. G. C. Lamb1, J. E. Larson*1, C. R. Dahlen2, and G. Marquezini1, 1North Central Research and Outreach Center, University of Minnesota, Grand Rapids, 2Northwest Research and Outreach Center, Crookston, MN.
Artificial insemination of superovulated Angus cows using sexed or conventionally frozen semen. G. C. Lamb*1, B. J. Lovaas1, S. L. Bird1, A. Martins1, J. E. Larson1, J. C. Rodgers1, D. J. Frank2, and D. M. Williams2, 1North Central Research and Outreach Center, University of Minnesota, Grand Rapids, 2ABS Global, Inc., DeForest, WI.
Effect of length of treatment with melengestrol acetate (7 vs. 13 days) prior to induction of ovulation on occurrence of short cycle in anestrous Nellore cows. O. G. Sa Filho*1, R. L. Valarelli2, and J. L. M. Vasconcelos1, 1FMVZ - UNESP, Botucatu, Brazil, 2Pfizer Animal Health, Brazil.
Effect of length of exposure to exogenous progesterone (3 vs. 6 days) prior to induction of ovulation on premature luteolysis in anestrous Nellore cows. O. G. Sá Filho*, C. R. Zilioti, and J. L. M. Vasconcelos, FMVZ - UNESP, Botucatu, Brazil.
Ovarian and hormonal responses to a progesterone releasing intravaginal device (PRID) treatment in the presence or absence of estradiol from the early luteal phase in heifers. T. Kuroiwa*, T. Tanaka, and H. Kamomae, Tokyo University of Agriculture and Technology, Fuchu, Tokyo, Japan.
A stochastic model to compare breeding system costs for synchronization of estrus and AI to natural service. S.K. Johnson* and R.D. Jones, Kansas State University, Manhattan.
Different estrus syncryonization protocols in sheep. B. R. Avila1, M. T. Sánchez1, E. O. García*2, O. D. Montañez-Valdez3, P. M Molina1, J. G. Peralta1, M. E. Ortega1, and J. L. Cordero1, 1Colegio de Postgraduados, Montecillo, Estado de México, México, 2Centro Universitario de la Costa Sur de la Universidad de Guadalajara, Aútlan, Jalisco, México, 3Centro Universitario del Sur de la Universidad de Guadalajara, Ciudad Guzmán, Jalisco, México.
Treatment with bST during progestin synchronization increases the blastocyst rate in ewes. A. Montero, J. Hernández, J. Valencia, C. G. Gutiérrez, S. Rojas, and J. Hernández-Cerón*, Facultad de Medicina Veterinaria y Zootecnia. Universidad Nacional Autónoma de México., Mexico.
Effect of estradiol–17β supplementation at the last GnRH of the Ovsynch protocol in lactating dairy cows. A. P. Cunha*, J. N. Guenther, E. P. B. Silva, J. B. C. Heijink, and M. C. Wiltbank, University of Wisconsin, Madison.
Effect of GnRH after TAI on subsequent Resynch fertility. A. P. Cunha*, J. A. Powell, J. N. Guenther, E. P. B. Silva, and M. C. Wiltbank, University of Wisconsin, Madison.
Human chorionic gonadotropin (hCG) and GnRH influences pregnancy survival and resynchronized ovulation before timed AI in Holstein cattle. B. S. Buttrey*, M. G. Burns, and J. S. Stevenson, Kansas State University, Manhattan.
Logistic regression analysis for relationship between the timing of the resumption of normal ovarian cycles and metabolic status in postpartum dairy cows. C. Kawashima*, M. Matsui, E. Kaneko, C. Amaya Montoya, T. Shimizu, N. Matsunaga, K. Kida, Y-I. Miyake, and A. Miyamoto, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido, Japan.
Does synchronization protocol affect conception in lactating dairy cows? J. L. M. Vasconcelos*1, R. M. Santos2, B. L. Cardoso1, F. M. Abreu1, L. H. Cruppe1, and S. Soriano3, 1FMVZ- UNESP, Botucatu, SP, Brazil, 2UFU, Uberlandia, MG, Brazil, 3Faz Colorado, Araras, SP, Brazil.
Effect of physiological status on the concentrations of progesterone maintained by CIDRs in Holstein cattle. K. T. Wolf*, A. K. Sanders, D. L. Ray, and W. J. Silvia, University of Kentucky, Lexington.
Effect of flunixin meglumine at days 15 and 16 after TAI on pregnancy rates in lactating Holstein cows. L. F. M. Pfeifer1, J. L. M. Vasconcelos*2, A. Schneider1, J. Wilson Neto1, N. J. L. Dionello1, P. Duarte1, L. Meneghelo1, M. N. Correa1, A. Guzeloglu3, and W. W. Thatcher4, 1UF Pelotas, Pelotas, Brazil, 2FMVZ, Botucatu, Brazil, 3Selcuk University, Konya, Turkey, 4University of Florida, Gainesville.
Effect of GnRH administered four days after synchronization of ovulation and timed AI on fertility of anovular lactating dairy cows. R. A.