A family farm in Castlerock: Focus on production and fertility
David and Jayne Conn robotically milk 100 cows along with their four children at Ardina Farm, close to Castlerock in Co Londonderry.
This is a new business, established on a green field site just four years ago. The Ardina herd is currently averaging 10,500L on a rolling basis at 4.5% fat and 3.55% protein.
David explained: “There is scope to expand milking cow numbers up to 120 given the availability of the two robots, and our year-round calving pattern. We have used sexed semen quite widely on the cows, giving us the opportunity to select the extra heifers that we need. Our priority has been to breed herd replacements with the ability to improve milk components while, at the same time, having good legs and feet, together with health traits. It all adds up to functional cows that will remain in the herd for a long number of lactations.”
Objectives
United Feeds’ Edel Madden is the Conn’s nutritional adviser. “When we began working with David and Jayne they had clear goals in mind; to increase milk quality, while maintaining yield and fertility, and to improve forage intakes. Over the last four years we have worked in partnership with David and Jayne to develop a strategy to help them achieve these goals.”
Current diet
Edel explain: “We have been working on ways to increase dry matter intake from forages, since the farm was established. I’m pleased that the current figure is at 12kg of forage dry matter intake per cow day. This has improved from below 10kgDM, through a combination of silage quality improvements and increased feed availability and space. In 2025 four cuts of silage were taken, the 1st cut analysed at 28% DM, 11.5ME, 48NDF & 14.5% CP. It’s our role at United Feeds to recommend the best feeding strategy that fully complements the available forages and optimises cow performance.
Edel continues: “Concentrates are fed by way of a basal TMR with nuts available through the robot on a feed to yield basis. The current TMR contains 4kg per cow of a customised blend, which is formulated to balance the forages fed. We include a rumen protected fat in both the blend and nut. This is to aid fatty acid production to support both milk quality and fertility. Protected fats can aid fertility in several ways; from supporting hormone production, to egg quality and body condition; all ultimately aiding conception rates.”
The Ardina Farm cows are currently being fed Supergold 17 nuts through the robot. This dairy nut contains our HerdCare mineral supplement which is unique in the Northern Irish market as it contains 100% organic Selenium, Zinc, Copper and Manganese. These have been proven to aid in fertility through supporting uterine health, enhancing embryo survival and therefore conception rates.
Liquid glycol is fed during early lactation through the robot. Propylene glycol is not only another energy source, but increases blood insulin and progesterone levels, hence improving heats and conception rates.
Mycotoxins
"This winter we identified a mycotoxin issue on the farm, which is common in many 2025 forages. Following the inclusion of Mycosorb A+ in the blend, David witnessed improvements in milk yield, dung consistency, and stabilised intakes, which were previously fluctuating. Mycosorb A+ is a broad-spectrum mycotoxin binder, helping mitigate the risks of mycotoxins by the method of adsorption. Adsorption is the process by which carbohydrate components of yeast and algae cell walls bind to mycotoxins, removing them from the animal’s digestive tract, while avoiding interactions with other minerals and nutrients.”
Fertility focus
David explains: “A service technician is used to inseminate both cows and heifers. There is no sweeper bull used. Sexed semen is used to breed herd replacements and beef straws are used on all other occasions.
The average age at calving of our 1st calving heifers is 24 months. In the dairy herd we are currently using 1.9 straws per pregnancy with 91% of cows back in calf within 100 days of calving. The current calving interval is 393 days.”
Milk quality
Edel concludes: “As one of the Conn’s main objectives, it’s really pleasing to see an increase in milk component production on the farm. Taking the most recent month of February for comparison, from 2024 to 2026 butterfat has risen from 4.38% to 4.55%, protein has risen from 3.30% to 3.48%, all while maintaining impressive yields.
"Since starting their dairy enterprise David and Jayne have taken on board our recommendations and challenged us to help them achieve their goals. The production figures and the cows are testament to their commitment to run a successful, healthy herd.”
If you would like to discuss the fertility or production performance of your herd, contact your local United Feeds nutritional adviser or call 028 9075 9000.