The Effect of Ovsynch Protocol Combine with Progesterone (PRID？) on Pregnancy Rate in Dairy Cows

The effects of ovsynch protocol combine with progesterone on pregnancy rate in dairy cows were investigated. A total of 50 Holstein-Fresian cows, divided into two groups were used. In groups 1 (G1; n=30) were received ovsynch protocol: GnRH (Gonadorelin diasetat tetrahidrat, 100 μg/cow, i.m., Ovarelin？, Ceva, Turkey) on d0, PGF2α (Dinoprost, 25 mg/cow, i.m., Enzaprost-T？, Ceva, Turkey) on d7, 2nd GnRH on d9 were applied and subsequent 16th hours artificial inseminatin were preformed. In Grup 2 (G2; n=20) unlike the G1 a progesterone source PRID-Delta？ (1.55 g Progesteron, Ceva, Tu？rkiye) were inserted intravaginally during day 0 to 7. Pregnancy diagnosis was performed by rectal palpation on days post-AI 45-60. Postpartum days 59.93±8.72 and 59.25±14.17 days (P>0.05); milk yield 26.16±4.93 and 28.80±6.77 kg (P>0.05); lactation number 1.90±0.53 and 1.75±0.44 (P>0.05); body condition scores 3.27±0.42 and 3.25±0.30 (P>0.05) were found for G1 and G2, respectively. When the groups were divided into two subgroups as pregnant and non-pregnant animals, there was no significance between the above parameters. Although the pregnancy rates as 60.00% in G2 supported by progesterone were higher than G1 (53.33%), there was not found significance between the groups (P>0.05). Conclusion: Applied progesterone to support ovsynch protocol may increase pregnancy rates and PRID may use this purpose. However more studies are needed to confirm the results