Maximise your heat detection efficiency
Getting the right cows mated at the right time is essential to maximise your herd’s 6 week in-calf rate.
There are many factors involved but there’s one in particular that is right front of us at mating time.
Heat detection efficiency is estimated to be a major opportunity to improve herd fertility in at least 25% of dairy farms according to research in both New Zealand and Ireland.
High performing farms detect more cows in heat with greater accuracy than lower performing farms.
Review your herd’s heat detection performance so you don’t miss this most immediate and arguably cheapest opportunity for herd improvement.
Reviewing your herd
1. Missed heats - am I mating enough cows?
Cycling cows that go undetected can lower your herd’s submission rate.
Look at your herd’s 3-week submission rate of the early-calved mature cows – your cows that are 4+ year’s old who calved in the first month of calving.
Target = 95%
If you have less than 90% of this group mated in the first 3 weeks of mating, it is very likely you’ve some missed heats.
2. Invented heats - am I mating the right cows?
Mating cows that are not truly on heat can lower your herd’s conception rate.
Usually heats occur at 21-day intervals. A short return occurs when the cow has had two matings less than 18 days apart. It is likely one of these matings occurred when the cow was not on heat. A small percentage of short returns is considered normal, so the target is set at less than 13%.
Check out your figures on your herd recording software or by highlighting all short-return matings on your mating chart.
If your figure is greater than 13% it’s possible you are mating cows which are not on heat. This not only wastes semen, but also risks pregnancy loss in pregnant cows
Tips to help maximise heat detection efficiency
- Review the signs of heat
- Spend time observing the sexually active group cows in the paddock
- Use two heat detection aids correctly (tail paint and a heat mount detector)
- Monitor your herd’s performance and seek your vet’s advice if you are not meeting targets
For more information, check out the chapter 13, page 103 in DairyNZ's The InCalf book