Stimulation of the Reproductive Functions at Acyclic Cows by Ovsynch and PRID/ eCG
Keywords:
acyclic cows, Ovsynch, PRID, eCGAbstract
The aim of our work was to compare the efficiency of two programs for induction and synchronization of estrus and ovulations in acyclic cows (Ovsynch and gestagene program (PRID) + eCG). At the first lot, of 63 cows, 2 mL Ovorelin (100 mcg GnRH), were administrated (0 day), in the 7th day 0.500 mg Cloprostenol were administered, in the 9th day 100 mcg GnRH were administered and after 16 hours artificial insemination was performed. At the 41 cows in the second lot, PRID (1.55g Progesteron) were inserted (0 day), in the 7th day 0.500 mcg Cloprostenol were administrated, in the 8th day PRID were redraw and 500 UI eCG were administrated, after 56 hours artificial insemination was preformed and 100 mcg GnRH were administrated. After 60 days from the artificial insemination 20 cows (31.7%) of from the first lot and 16 cows (39%) from the second lot, were diagnosed as pregnant, the differences are significant (p <0.05). Both protocols used for stimulation of reproductive function in acyclic cows is inducing the grouping of the oestrous and ovulations, which allows the fixed term insemination. The oestrus inducing programme with progestagene (PRID) and eCG induction seams more efficient in acyclic cows.
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