STUDIES REGARDING THE CONCEPTION RATES AT DAIRY COWS

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 PgF 2 α 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.