1. Arndt, W.J., J. Andrew, M.L. Bauer, J.D. Kirsch, D.E. Schimek, K.G. Odde and K.A. Vonnahme. 2009. Effect of post-insemination progesterone supplementation on pregnancy rate in dairy cows. Canadian Journal of Veterinary Research, 73: 271-274.
2. Ataman, M.B., H. Erdem, B. Bulbul, S. Umutlu and M. Çolak. 2011. The effect of buserelin injection 12 days after insemination on selected reproductive characteristics in cows. Acta Veterinaria Brno, 80: 171-177. [
DOI:10.2754/avb201180020171]
3. Beal, W.E. 2003. Estrous Synchronization and ai in cattle, department of animal and poultry science virginia polytechnic and state university. Blacksburg. 24061-0306. Thesis, 30-32.
4. Bülbül, B., M. Kırbaş, M. Köse, S. Dursun and M. Çolak. 2009. The effects of ovsynch started in Different Phases of oestrus cycle on oestrus synchronization in cows. İstanbul universitesi veteriner fakultesi dergisi, 35: 7-17.
5. Burns, D., S. Fermin, J.L. Jimenez-krassel, H. Ireland, P.G. Knight and J.J. Ireland. 2005. Numbers of Antral Follicles during Follicular Waves in Cattle: Evidence for High Variation among Animals, very high Repeatability in Individuals and an Inverse Association with Serum Follicle-Stimulating Hormone Concentrations. Biology of Reproduction, 73: 54-62. [
DOI:10.1095/biolreprod.104.036277]
6. Çınar, M. 1999. The Effect of GnRH Application at Insemination and/or 12 Days after the Insemination on Fertility in Dairy Cows Synchronized with PGF2α. PhD Thesis, SÜSBE, Konya, 15-17.
7. Dirandeh, E., H. Kohram and A. ZareShahneh. 2009. GnRH Injection before Artificial Insemination (AI) Alters Follicle Dynamics in Iranian Holstein Cows. African Journal of Biotechnology, 8: 3672-3676.
8. Dirandeh, E., A. Towhidi, S. Zeinoaldini, M. Ganjkhanlou and Z. Ansari Pirsaraei. 2013. Effects of different pufas supplementation during the postpartum periods of early lactating dairy cows, I: Milk Yield, Metabolic. Journal of Animal Science, 90: 1-9. [
DOI:10.1071/RDv25n1Ab216]
9. Dirandeh, E., A. Rezaei Roodbari and B. Shohreh. 2014a. Effect of GnRH injection at day 6 and 12 after insemination on fertility of Holstein dairy cows during the warm season. International Journal of Advanced Biological and Biomedical Research, 2: 125-131.
10. Dirandeh, E. 2014b. Starting ovsynch protocol on day 6 of first postpartum estrous cycle increased fertility in dairy cows by affecting ovarian response during heat stress. Animal Reproduction Science 149: 135-40. [
DOI:10.1016/j.anireprosci.2014.07.018]
11. Diskin, M.G., E.J. Austin and J.F. Roche. 2002. Exogenous hormonal manipulation of ovarian activity in cattle. Domestic Animal Endocrinology, 23: 211-228. [
DOI:10.1016/S0739-7240(02)00158-3]
12. Drew, S.B.and A.R. Peters. 1992. The effect of treatment with a gonadotrophin releasing hormone analogue on the fertility of dairy cows. Proceedings of the 12th international congress on animal reproduction, hague, Netherlands, 319 pp.
13. Eddy, R.G., O. Davies and C. David. 1991. An Economic Assessment of Twin Births in British Dairy Herds. Veterinary Record, 129: 526-529.
14. Fouladi-Nashta, A.A., C.G. Gutierrez, J.G. Gong, P.C. Garnsworthy and R. Webb. 2007. Impact of Dietary Fatty Acids on Oocyte Quality and Development in Lactating Dairy Cows. Biology of Reproduction, 77: 9-17. [
DOI:10.1095/biolreprod.106.058578]
15. Hanlon, D.W., P.J. Davidson, A.R. Hittmann and A.K. Joe. 2005. Supplementing Previously Treated Anestrous Dairy Cows with Progesterone does not Increase First-Service Conception Rate. Theriogenology, 63: 239-245. [
DOI:10.1016/j.theriogenology.2004.04.008]
16. Jemmeson, A. 2000. Synchronising ovulation in dairy cows with either two treatments of gonadotropin-releasing hormone and one of prostaglandin, or two treatments of prostaglandin. Australlian Veterinary Journal, 78:108-111. [
DOI:10.1111/j.1751-0813.2000.tb10536.x]
17. Kafi, M., M. Zibaei and A. Rahbari. 2007. Accuracy of estrous detection in cows and its economic impacts on Shiraz dairy farms. Iranian. Journal of Veterinary Research, 8: 131-137.
18. Kastelic, J.P. 1994. Noninfectious embryonic loss in cattle. Veterinary medicine, 6: 584-589.
19. Lopez-Gatius, F., P. Santolaria, J.L. Yaniz and R.H. Hunter. 2004. Progesterone supplementation during the early fetal period reduces pregnancy loss in high-yielding dairy cattle. Theriogenology, 62: 1529-1535. [
DOI:10.1016/j.theriogenology.2004.02.005]
20. Lopez-Gatius, F., P. Santolaria, A. Martino, F. Dele'tang and F. De Rensis. 2006. The effects of gnrh treatment at the time of ai and 12 days later on reproductive performance of high producing dairy cows during the warm season in northeastern Spain. Theriogenology, 65: 820-830. [
DOI:10.1016/j.theriogenology.2005.07.002]
21. Mann, G.E., G.E. Lamming and M.D. Fray. 1995. Plasma oestradiol and progesterone during early pregnancy in the cow and the effects of treatment with buserelin, Animal Reproduction Science, 37: 121-131. [
DOI:10.1016/0378-4320(94)01325-G]
22. Markusfeld-Nir, O. 1997. Epidemiology of bovine abortions in Israeli dairy herds. Preventive Veterinary Medicine, 31: 245-255. [
DOI:10.1016/S0167-5877(96)01142-7]
23. Moreira, F., R.L. De La Sota, T. Diaz and W.W. Thatcher. 2000. Effect of day of the estrous cycle at the initiation of a timed artificial insemination protocol on reproductive responses in dairy heifers. Journal of Animal Science, 78: 1568-1576. [
DOI:10.2527/2000.7861568x]
24. Paksoy, Z. and C. Kalkan. 2010. The effects of GnRH and hCG used during and after artificial insemination on blood serum progesterone levels and pregnancy rate in cows. Kafkas Universities Veteriner Fakultesi Dergisi, 16: 371-375.
25. Peters, A.R., T.A. Martinez and A.J. Cook. 2000. A Meta-Analysis of the Effect of GnRH 11-14 Days after Insemination on Pregnancy Rates in Cattle. Theriogenology, 54: 1317-1326. [
DOI:10.1016/S0093-691X(00)00438-6]
26. Rettmer, I., J.S. Stevenson and L.R. Corah. 1992. Endocrine responses and ovarian changes in inseminated dairy heifers after an injection of a GnRH Agonist 11 to 13 days after estrous. Journal of Animal Science, 70: 508-517. [
DOI:10.2527/1992.702508x]
27. Robinson, J.J., C.J. Ashworth, J.A. Rooke, L.M. Mitchel and T.G. Mcevoy. 2006. Nutrition and fertility in ruminant livestock. Animal Feed Science and Technology, 126: 259-276. [
DOI:10.1016/j.anifeedsci.2005.08.006]
28. Sato, T., K. Nakada, Y. Uchiyama, Y. Kimura, N. Fujiwara, Y. Sato, M. Umeda and T. Furukawa. 2005. The effect of pretreatment with different doses of gnrh to synchronize follicular wave on superstimulation of follicular growth in dairy cattle. Journal of Reproduction and Development, 51: 5-14. [
DOI:10.1262/jrd.16070]
29. Schmitt, E.J.P., T. Diiaz, C.M. Barros, R.L. De La Sota, M. Drost, E.W. Fredriksson, C.R. Staples, R. Thorner and W.W. Thatcher. 1996. Differential response of the luteal phase and fertility in cattle following ovulation of the first-wave follicle with human chorionic gonadotropin or an agonist of gonadotropin-releasing hormone. Journal of Animal Science, 74: 1074-1083. [
DOI:10.2527/1996.7451074x]
30. Sheldon, M. and H. Dobson. 1993. Effects of gonadotrophin releasing hormone administered 11 days after insemination on the pregnancy rates of cattle to the first and later services. Veterinary Record, 133: 160-163. [
DOI:10.1136/vr.133.7.160]
31. Sheldon, M. 1997. Bovine fertility-practical implications of the maternal recognition of pregnancy. In Practice. 6: 546-556. [
DOI:10.1136/inpract.19.10.546]
32. Sterry, R.A., M.L. Welle and P.M. Fricke. 2006. Treatment with gonadotropin-releasing hormone after first timed artificial insemination improves fertility in noncycling lactating dairy cows. Journal of Dairy Science, 89: 4237-4245. [
DOI:10.3168/jds.S0022-0302(06)72469-9]
33. Stevenson, J.S., A.P. Phatak, I.M.M.O. Rettmer and R.E. Stewart. 1993. Post Insemination Administration of Reeptal: Follicular Dynamics, Duration of Cycle, Hormonl Responses, and Pregnancy rates. Journal of Dairy Science, 76: 2536-2547. [
DOI:10.3168/jds.S0022-0302(93)77589-X]
34. Stevenson, J.S., Y. Kobayashi, M.P. Shipka and K.C. Rauchholz. 1996. Altering Conception of Dairy Cattle by Gonadotropinreleasing Hormone Preceding luteolysis Induced by Prostaglandin F2α. Journal of Dairy Science, 79: 402-410. [
DOI:10.3168/jds.S0022-0302(96)76379-8]
35. Szenci, O., E. Taka, J. Sulon, N. Melo de Sousa and J.F. Beckers. 2006. Evaluation of GnRH treatment 12 days after AI in the reproductive performance of dairy cows. Theriogenology, 66: 1811-1815. [
DOI:10.1016/j.theriogenology.2006.04.034]
36. Walton, J.S., G.W. Halbert, N.A. Robinson and K.E. Leslie. 1990. Effects of progesterone and humanchorionic gonadotropin administration five days postinsemination on plasma and milk concentrations of progesterone and pregnancy rates of normal and repeat breeder dairy cows. Canadian Journal of Veterinary Research, 54: 305-308.
37. Zuluaga, J.F. and G.L. Williams. 2008. High-pressure steam sterilization of previously used CIDR inserts enhances the magnitude of the acute increase in circulating progesterone after insertion in cows. Animal Reproduction Science, 107: 30-35. [
DOI:10.1016/j.anireprosci.2007.06.006]