STUDIES REGARDING THE CONCEPTION RATES AT DAIRY COWS
Keywords:
cow, pregnancy rates, synchronization, PgF2 α, GnRHAbstract
The conception rate is defined as the aptitude of a female to romaine pregnant after
the first A.I. and represents the proportion between the number of pregnant cows at
first A.I and the number of cows inseminated in that period. In our experiments of
estrus induction and synchronization, in order to increase the pregnancy rates, we
used the Ovsynch protocol and other protocols for PgF2α and GnRH. In order to
establish the pregnancy rates, the number of females that have not return in heats
after A.I. were taken in consideration. The conception rates were 45.5 – 52.6%. The
estrus synchronization offers the possibility to increase the pregnancy rates at first
service after calving and creates the possibility to inseminate at certain time without
heat detection.
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