Genomics streamlines herd breeding and health progress (Sept 25)

Accessing advanced and accurate management data generated by genomic testing is supporting improved herd health, efficiency and productivity on one Northern Ireland-based unit.

TEXT KAREN WRIGHT

There’s no standing still for Stephen Morrison and his father David when it comes to embracing new technology that will promote genetic potential, and sustain productive, healthy and longer-lasting cows. They run the 220-cow Holstein herd at Armoy, County Antrim. These high production all-round cows regularly scoop NMR herd-performance awards.

Cows are housed all year round, and a robotic milking system was introduced in 2014 to save labour and improve cow welfare. “Yields were steadily rising, so we felt cows needed milking more often,” says Stephen.

Automation has been key to their progress. “We’ve also added robotic scrapers, a feed pusher and fans to control temperature. And we’ve streamlined herd management to reduce labour requirements.

“There’s just my father and me on the farm and I have three young sons, so the work–life balance is important,” he adds.

Herd average yield stands at 12,193kg of milk at 4.31% fat and 3.43% protein. Cows average 3.1 visits to the robot daily. Milk is sold to Dale Farm, which pays for milk solids, so this has been the focus in the Morrison’s breeding plans, alongside improved cow health and longevity.

“Improved production had to be efficient and come from healthy and fertile cows,” says Stephen.

Genetic progress

Looking to maximise progress and increase efficiency, they started genomic testing heifers in 2019. After six years, all cows in the milking herd now have a genomic test.

The Morrisons use the Clarifide Plus genomic testing service through Riada Vets’ Adam Conn. This tool provides an index that takes production and health traits into account and is used to select animals to breed the next generation of milkers from.

Using genomic data to select animals to breed from has increased their rate of improvement. “Milk solids have improved significantly in the past six years, and milk yields have continued to increase too,” says Stephen.

“Pre robots the average was 9,000kg a cow,” he adds. Stephen admits that genomic testing has been an interesting journey. When they started genomic testing, only about 60% of heifers made the cut for breeding replacements, but now most do. “But there are always exceptions, and it’s confirmed the need to believe in the data and not follow instinct which can be wrong.

“Just last year, in 2024, we had a heifer that looked the part, but her genomic results didn’t stack up and we followed the data and didn’t breed her to a dairy sire. Sure enough, she didn’t get back in calf, and ended up having poor legs and feet,” explains Stephen, adding that pre genomics they’d bred from cows that looked good, but their udders dropped by their third lactation.

“Relying on visual assessment isn’t as accurate as genomic tests. Most likely, these ‘good-looking’ cows wouldn’t have been bred from if we’d had their genomic data. During the past six years, we’ve gained a lot of valuable experience to give us the confidence to put our trust in genomic testing.”

Half the milking herd are bred to sexed dairy semen with each mating carefully planned based on sire and dam genomic data. The aim is to produce 90 to 100 heifer calves a year.

The rest of the herd is bred to beef sires and most of these crossbred calves are reared to finishing on the farm. In total the farm carries about 500 head of stock.

Cell counts

A fully genomically tested herd has enabled Stephen to take advantage of NMR’s GenoCells service that can provide individual somatic cell counts simply from a bulk-milk sample DNA test.

Herds genomically tested using the NMR laboratory, which includes Zoetis’ Clarifide service and other UK genomic service providers, can access individual somatic cell counts (SCCs) for each cow from one bulk milk test. The GenoCells test matches the SCC with the DNA of the cow.

“This is an attractive option for our robotically milked cows,” says Stephen. “As Clarifide users, GenoCells is available to us.”

He alternates each month between GenoCells, where he takes a bulk-milk sample himself for SCC testing, with the NMR shuttle service which provides a complete milk-recording service.

Simple approach: Stephen takes a bulk-tank milk sample for GenoCells SCC test

Milk-sampling shuttles are set up on the farm by NMR – one for each robot. The shuttle is attached to the robot for 24 hours to ensure a milk sample is collected from each cow, which is then tested and provides individual cow butterfat and protein results, as well as SCC. Every quarter, the sample is also used for a Johne’s screen through NMR’s HerdWise service.

This ‘blended’ service means that Stephen only has the cost of shuttle hire six times a year but it still provides the required recording information for his pedigree purposes.

“Somatic cell count results via GenoCells and shuttles are very comparable,” says Stephen. “So we can rely on GenoCells for our cows’ SCC results every other month. And it’s far easier and less time-consuming for us.”

Average SCC for the herd is 132,000 cells/ml and any blips in levels are dealt with immediately to mitigate problems. SCC data is also used for selective dry-cow treatment. Only 40% of cows receive an antibiotic at drying off, and the aim is to reduce this further. All cows have a teat sealant applied.

“We record all the data through Uniform software and we can soon pick up deviations from our targets,” he adds.

The Morrisons also follow strict biosecurity rules, so problems are minimised, and this applies particularly to Johne’s disease control. “Our routine screening results show that infection rates are dropping and we’ve only five cows out of the herd with any signs of Johne’s infection.” Performance data is also monitored alongside body condition score, dung consistency and fertility.

Home-grown forage

“We’re a high input herd, but we put a lot of effort into getting as much feed value as we can from our own forage,” adds Stephen. “We aim for more than 35% dry matter and a ME of 12MJ/kg DM. The aim is to produce a third of the milk from home-grown forage.”

Silage samples are tested on a regular basis and diets balanced by Thompson’s nutritionist Mary-Jane Robinson. While there are no plans – or capacity – to increase cow numbers, Stephen is future-proofing the business by targeting year-on-year improvements. “The aim is to have more cows nudging a tonne of milk solids per lactation through their natural ability and not by being put under any stress,” he explains.

If the next generation is keen to keep the business going, we’ve got to maintain progress. There’s some good technology out there which we’ll continue to tap into.”