More of the Otago dairy herd got pregnant in the first six weeks of mating in the 2025-26 season compared with the previous year, which helped set a national record for the metric.
Livestock Improvement Corporation (LIC) collates data from more than 2.6 million cows in New Zealand.
LIC chief executive David Chin said the data showed the national six-week in-calf rate had risen to a new record of 70.4% in the 2025-26 season, up from 70.2% the season before.
The 6-week in-calf rate is used by farmers to measure the reproductive efficiency and profitability of their herds.
Reproductive performance varied across the country, softer results in the North Island offset by stronger performance in the South Island.
Standout gains were seen in Otago, South Canterbury and Canterbury, where six-week in-calf rates lifted by between 1.4% and 2.5% compared to last season.
Otago had the biggest gain, increasing from 68.9% to 71.4%, while South Canterbury lifted from 70.6% to 72.6% and Canterbury increased from 70.5% to 71.9%.
In the North Island, results eased slightly, with Waikato shifting from 71.2% to 69.6% and Northland from 71.0% to 69.2%.
The reproduction outcomes were influenced by a range of factors, including seasonal and weather conditions, which could affect pasture quality and how cows recovered heading into mating, Mr Chin said.
"Given some of the conditions parts of the North Island experienced this season, maintaining overall national performance and seeing a slight lift is a good outcome."
Stronger South Island performance was likely supported by favourable pasture conditions and farmers investing in quality feed through mating.
"Preparation before mating remains one of the biggest influences on getting cows back in calf."
The industry’s top-performing 25% of herds achieved a six-week in-calf rate of 78.2%.
The rate of empty cows between the two seasons had remained relatively stable at 14.7%.
