Heat detection plays a central role in how New Zealand dairy farms manage fertility, pasture utilisation, and overall herd efficiency. In a unique pasture-based system built around efficient spring calving, the timing of your mating decisions has flow-on effects that will last your entire season and guide your decisions around culling.
When cows on heat are identified accurately and inseminated at the right time, you’ll maintain a better six week in-calf rate and your herd will maintain a tighter calving pattern. That outcome supports milk production targets while keeping animal health pressures manageable and let you bank extra days in milk.
Research out of DairyNZ has consistently highlighted reproductive performance as a key driver of farm profitability, noting that submission rates in the first three weeks of mating strongly influence six-week in-calf rates.
What’s the point of heat detection?
Heat detection refers to the process of identifying cows that are in oestrus and therefore ready to be mated. Behavioural signs such as standing to be mounted, restlessness, and changes in grazing patterns remain relevant in New Zealand’s grazing systems. Many farms still rely on observation because typically, cows spend nearly their whole life in the paddock. This approach demands consistency, experience, time, and a very keen eye.
It’s safe to say during busy spring periods, observation quality can vary which affects heat detection accuracy and downstream reproductive performance – important because farmers are spending more on premium dairy genetics to achieve genetic gain in their herd.
Reproductive performance improves when heat detection remains accurate and timely across the mating period. Submission rate, conception rate, and empty rate all respond to how well heats are identified. According to DairyNZ, herds that achieve higher six-week in-calf rates often maintain more consistent milk production later in the season because fewer late-calving cows enter peak lactation out of sync with pasture supply. Heat detection therefore is an important link between biological outcomes and feed efficiency.
What options do I have?
Tail paint remains common in New Zealand because it suits outdoor environments and requires a low cost of entry. Electronic systems such as wearables attract interest because they offer continuous monitoring and data storage. And self-adhesive patches or scratch packs like Beacon Heat Seeker or ScratchE are becoming more popular for their ease of application and usefulness.
What product should I buy?
The question of “what heat detection should I buy?” often arises when farmers assess labour availability, herd size, and existing technology on farm, and the right choice usually depends on how well the system fits daily routines rather than on technical features alone.
If you’re able to invest the capital into on-farm wearables, it’s a great option to having better oversight and insights into your herd. However, most farmers will rely instead on adhesive packs or tail paint, and there are benefits to both.
Tail paint is a low-cost, easy and distinctive identifier for a cow on heat, whereas patch packs and scratch packs are far better at showing how much bulling or mounts have occurred, giving you better insights.
Why does precision heat detection matter?
It matters that farmers understand heat detection as part of a wider reproductive strategy. No single tool compensates for inconsistent mating decisions or poor animal health. Body condition score, nutrition, and lameness management all influence how clearly cows express heat. An obvious example is research has shown that lame cows show reduced mounting behaviour, which directly affects heat detection success.
Farmers who address these factors tend to see steadier reproductive performance over time.
Heat detection remains a practical, day-to-day discipline on New Zealand dairy farms. It connects animal behaviour, technology, and management skill in a way that directly influences seasonal outcomes. In a spring-calving system, small gains in heat detection accuracy often translate into meaningful improvements in reproductive performance. For farmers weighing options and asking which heat detection product should I buy, the most effective solution usually supports existing workflows and reinforces good stock observation. When heat detection works well, it strengthens the entire production system rather than acting as a standalone fix.
Where to buy heat detection products
Beacon Heat Seeker
Marketed by World Wide Sires New Zealand
Email: office@wwsires.co.nz
Phone: 03 338 4560
Website: wwsires.co.nz
FIL Tail Paint
Sold by GEA
Email: office.fil@gea.com
Phone: 0508 434 569
Website: fil.co.nz
Bulls-i
Marketed by LIC
Email: reception@lic.co.nz
Phone: 07 856 0700
Website: lic.co.nz
Tail Alert
Sold by Donaghys
Email: sales@donaghys.co.nz
Phone: 0800 942 006
Website: donaghys.co.nz