TY - JOUR TT - The Effect of Reduced Dose of GnRH Administered at the Time of Insemination on Pregnancy Rate in Lactating Dairy Cows AU - Sertkol, Ramazan AU - Sarıbay, Mustafa Kemal PY - 2017 DA - June JF - Harran University Journal of the Faculty of Veterinary Medicine JO - Harran Univ Vet Fak Derg PB - Harran University WT - DergiPark SN - 2146-7188 SP - 46 EP - 50 VL - 6 IS - 1 KW - İnek KW - GnRH KW - Gebelik oran N2 - This study was carried out to determinethe effect of reducing half dose of GnRH performed immediately at the time ofartificial insemination on pregnancy rate in lactating dairy cows.  The study was conducted on 50 Holstein cowsaging between 3-6 years old, and on 80-120 days postpartum without reproductiveproblems. No hormonal application wascarried out for ensuring estrous in cows. The ovarian examinations of the cowsshowing estrous symptoms were performed by real-time ultrasound with 6–8MHz lineer probe and the diameters of the follicles were recorded. The cows inGroup I (n=25), a gonadotropin releasinghormone (GnRH) analogue,buserelin acetate (Receptal®, İntervet) recieved 2.5 ml of GnRH intramucularly  just at the time of artificialinsemination. Group II recieved 1.25 mL of GnRH,intramuscularly immediately atthe same time.  The diameters offollicles at the time of inseminations were detected as 12.28±0.37 mm, 12.24±0.44 mm in the group I andgroup II respectively. The pregnancy rates were 80% (20/25) and 72% (18/25), ingroup I and group II respectively (P>0.05). It was concluded that reducingthe half dose of GnRH, which is performed to increase the pregnancy rate incows immediately at the time of insemination, did not affect the pregnancyrate. CR - Alaçam E, T Tekeli, Gökçay Y, 1986: Sütçü ineklerde gonadotropin salgılayıcı hormon (gnrh) enjeksiyonu ile gebelik oranlarının yükseltilmesi üzerinde çalışma. Eurasian J Vet Sci, 2, 1, 27- 35. CR - Alaçam E, 1999: İnekte infertilite sorunu. 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