Ovsynch based protocols in reproductive management and infertility treatment in dairy cows - when and why?

In order to optimise reproductive performance and thus production, it is now impossible to control the reproduction of dairy cows without the use of hormones. Due to the characteristics of dairy cows, the use of hormones not only reduces the need for visual heat detection and thus the number of undetected cows in heat, but also prevents certain problems associated with intensive production and its negative effects on reproduction. Ovsynch, as a planned combination of GnRH and PGF2α that allows artificial insemination at the optimal time without the need to control ovaries and uterus, once offered solutions to these problems, but over time its shortcomings were recognised. Therefore, pre-synchronisation protocols have been developed to create optimal conditions for Ovsynch and allow for the best outcome. In addition to pre-synchronisation, Ovsynch and its modifications can also be used in the resynchronisation of inseminated and sonographically diagnosed non-pregnant cows as soon as possible, improving farm efficiency. The addition of progesterone implants also further improves the performance of Ovsynch-based protocols. In addition to controlling reproduction, Ovsynch and its modifications have also proven successful in treating certain forms of infertility in dairy cows, such as anovulatory conditions and cystic ovarian disease. This paper presents the possibilities of using the Ovsynch protocol and its various modifications, and their advantages and disadvantages.