So you’ve got a plan agreed to treat non-cyclers to ensure they ovulate and are inseminated on the first day of mating.

What’s next? There is another step that helps tighten calving spread, with all the associated benefits including more days in milk, better early submission rates next spring and improved cow longevity.

It’s called Why Wait, and is designed to help maximise early in-calf rates, as part of a proactive mating management strategy.

The principle is simple.  A single prostaglandin (PG) injection can bring cycling cows forward a week, meaning that essentially all cows in the herd ovulate and are inseminated in the first two weeks of mating.

For instance, cows cycling during the week before the PSM are generally not mated until the third week of mating.  By identifying this group, and then a few days later administering a single injection of PG, the cows cycle much sooner, during the first two weeks of mating.

Similarly cows on heat 7 to 14 days prior to PSM can be injected with PG two days prior to PSM, and will also cycle sooner, in the first few days of mating, instead of during the second week of mating.

Cows cycling between 14 and 21 days prior to PSM will cycle in the first week of mating anyway, so no PG is required for this group.  Refer diagram below.

New Zealand studies have shown that cows mated to a heat brought forward by PG have significantly higher in-calf rates and an extra 3 days in milk. This gives an estimated 3:1 return on investment with additional milk income far exceeding treatment costs and extra feeding costs of the extra days in milk. 

It is important to note that the success of a Why Wait program does rely on accurate heat detection, as well as good organisation and planning.  There are now Apps are available, such as 'Ready to Mate' from AgriHealth which can help you plan and manage repro programs including the Why Wait program, non-cycling cow treatments, metrichecking and tail painting.

Call the clinic today for a chat about using a Why Wait programme in your system.