Heat synchronisation involves treatment of cows with reproductive drugs in order to predictably time when their next heat and/or ovulation will occur.
Heat synchronisation can offer efficient use of labour, as the work of heat detection and AI is shortened into planned, intensive periods.
In seasonal and split herds, it can be used to compress three cycles of breeding (nine weeks) into a seven-week mating program, or two cycles (six weeks) into a four-week mating program.
Synchronisation programs may help increase heat detection rates in large herds, if people are less skilled or have limited time because the people detecting heat can focus on the job for short, predicted periods.
However, most synchronisation programs will have a limited effect on in-calf rates. Therefore, the management benefits should be the biggest consideration when deciding whether to use synchronisation or not.
When detecting heat during a synchronisation program, simple aids such as tail painting or heat mount detectors are essential.
Some synchrony programs require fixed timed inseminations, meaning that no heat detection is required at all during that period. Some synchrony programs allow resynchronisation of returns to service to help achieve increased heat detection rates for returns to service.
If considering using heat synchronisation for the first time, consult your ReproRight advisor or a veterinarian who has experience using heat synchrony options.
Guide to synchrony programs dairy factsheet(09 July 2020)PDF, 2.11 MB