AVA Conference Adelaide 2016

Ovsynch has been commonly used to synchronise lactating cows for fixed-time AI since the 1990s. Since Ovsynch results in a fixed-time AI, the pregnancy rate achieved is usually determined by the conception rate. In a year-round calving herd, lactating cows are often synchronised at the farm’s veterinary herd health visits after a negative pregnancy test or after showing no visible oestrus (NVO). Due to the use of transrectal ultrasound for pregnancy testing, veterinarians can now accurately determine the presence and size of ovarian structures at the time of synchronisation. Together with farm records and disease history, veterinarians have access to a considerable amount of information that can be used to assess the risk of conception. This presentation outlines which factors have an effect on conception rate and discusses treatment options for cows with particular ovarian structures