Simmental Irkı İneklerde Optimum Gönüllü Bekleme Süresi ve Senkronizasyon Programının Belirlenmesi

Abstract

The objective of the present study was to compare four different synchronization protocols at the end of various voluntary waiting period (VWP) and evaluate the effect of parity and milk yield on pregnancy rates with synchronization in Simmental cows. All animals were randomly allocated into four synchronization groups and one control group. Parity, milk yield (≤23 kg/d; >23 kg/d), and days in milk (DIM; 45-60, 61-90, >90 days) were compared according to synchronization protocols. Ovsynch (Group I; n=81), Ovsynch+Progesterone (Group II; n=30), G6G (Group III; n=66), 2xG6G (Group IV; n=45), and a control group (n=35) were designed for the study. The parity significantly affected the pregnancy rates in the primiparous cows, especially in Group II (P0.05). There was no significant difference between milk yield and pregnancy rates (P>0.05). In conclusion, the synchronization of Simmental cows with Ovsynch, Ovsynch+Progesterone, G6G, or 2xG6G did not affect pregnancy rates across various DIM. These data suggest that the suitable VWP could be planned according to the farm’s economic and local market targets, with veterinarians able to choose a protocol based on practicality, effectiveness and cost, as well as the specific requirements of the herd.