Breeding the ultimate robot-ready Jersey herd using robotic data

July 2026. Article by: Rick Majoor

In the beautiful, scenic expanse of Invercargill in New Zealand's South Island, Joanne (Jo) Crack of Southern Star Farms is redefining what it means to run a modern, self-sufficient dairy operation. Managing a 456-hectare farm near the Waituna Lagoon, Jo balances a 350 to 370-strong Jersey cow herd alongside 2,000 ewes and some beef stock. The farm’s transition from a conventional system to an automated grazing setup powered by four Lely Astronaut A5 robots, has completely revitalised their business and family lifestyle.

Southern Star Farms didn’t always look this way. Jo and her family started on a smaller, conventional dairy farm further up the road, milking up to 400 cows in an old herringbone shed. While they loved the industry and the animals, they quickly discovered two major pain points: they disliked the day-to-day grind of putting cups on cows, and they did not want to manage outside staff.

The logical step was to bring the cows home to their main property, downsize the herd slightly to focus on efficiency, and let automation take over the labour. Now, the dairy unit thrives at the top of the farm, while the sheep occupy the bottom acreage furthest from the lagoon.

The transition has empowered Jo to manage the bulk of the operation mostly by herself. When peak seasons arrive, family support steps in seamlessly. Her husband, Darren, helps train heifers in the mornings and evenings, and the second generation - daughter Kimberly and daughter-in-law Annabel - can walk in and run the system with zero formal training. "The system is pretty easy to follow," Jo notes, explaining that she simply leaves a list on the wall for them to reference.

Operating on a peaty soil base that naturally keeps the animals above the mud, Southern Star Farms features a highly strategic grazing layout. Nearly four years ago, they added a barn to the property to protect the pastures and house the winter milkers during Southland’s frequently rough weather spells.

While the farm originally launched with a three-way grazing model, Jo quickly realised that optimising cow flow required an upgrade to a strict four-way grazing system (A, B, C, and D blocks). Under this system, the herd spends exactly six hours in each even break across a 24-hour period.

According to Jo, keeping the blocks perfectly identical is the secret to a steady, predictable robotic system. If the allocations are uneven, cow flow becomes erratic, causing large groups to bottleneck at the lounge. By utilising four even intervals, the cows achieve an optimal milking frequency of two to three times a day, voluntarily spreading their traffic evenly across the day and night.

One of Jo’s greatest passions is cow genetics, and the Lely system has completely transformed her breeding program. Dissatisfied with overseas catalogues - where bulls are marketed as "robot ready" but fail to perform under real-world automated conditions - Jo took matters into her own hands.

By extracting deep data from her Lely Horizon management software, Jo meticulously monitors metrics like milk speed, culling information, and the performance of specific cow families. This level of granularity simply isn't available in conventional systems, or even in large rotaries according to her.

"The last few years I've actually been keeping bulls from those families, and the resulting progeny, there's no surprises with them," Jo says. "They milk exactly as I expect them to and generally better than anything I get out of the catalogues."

This customised breeding approach has driven consistent, year-on-year production increases without expanding the herd size. Seeing her top Jersey cows regularly achieve 800 to 900 kilograms of milk solids has set a new benchmark for what her entire herd could achieve.  

Reflecting on their journey, Jo stands firmly by a sentiment she shared back in 2024: "If we hadn't put in the robots, we wouldn't be dairying right now. Robots have given us freedom and taken the stress away." Today, that statement remains entirely accurate. The automation allows the family to handle a highly diversified workload - including raising all their own Jersey replacements, selling yearling bulls, growing out beef crossbreeds, and managing their own cultivation and muck spreading - without burning out.

Looking ahead, Jo sees virtual fencing as the next evolutionary step for their property, which would allow her to shift grass breaks right from her phone and potentially explore batch-milking groups to minimise cow walking distances.

For any dairy farmers currently sitting on the fence, Jo's advice is to visit as many robotic farms as possible to see how different operators tinker with the technology to suit their goals. She believes it is the ultimate tool for multi-generational farms. It allows older generations to stay actively involved in the yard without enduring the physical toll and grueling hours of traditional dairying, while simultaneously offering the tech-driven, low-stress lifestyle that younger generations demand.