A family tradition of dairying going back more than a century will end next month with the sale of a leading Norfolk pedigree herd.

It is a bitter wrench for Gavin Paterson, in his 60th year of farming in Norfolk, but the harsh economics of the lowest milk prices in Europe have forced the decision.

Mr Paterson, who was a director of Norwich City for 12 years from 1985 and the driving force behind the Worstead Festival for 40 years, is dispersing the milking portion of the Smallburgh and Lyngate herds.

A total of about 240 cows and heifers will be sold by auctioneer Wright Manley on Tuesday, October 25 at Beeston Castle, Cheshire.

However, Mr Paterson, who was made an MBE in the 2006 new year's honours, will retain about 160 head of young heifers until they calve and then they will be sold.

The Holstein Friesian herd includes two of the dairying's most famous names, which won the industry's supreme awards at the International Dairy Show.

On their debut at Olympia in 1953, his late father, James, won with Smallburgh Brenda. Then 17 years later at the capital's last Dairy Show, at Olympia in October 1970, it was Mr Paterson's turn to be presented with the supreme trophy of the Royal Association of British Dairy Farmers by Princess Alexandra.

Their cows had won on their debut with herdsman, George Clare, and at the last international show George's son Arthur was in charge.

In dairy showing, this achievement was unique because no other father and son, with separate herds of any breed, have ever won this top award and no other father and son stockmen have brought them out.

Cows have been central to the family's farming. In 1925, Mr Paterson's father moved from a 70-acre hill farm in Lanarkshire, where he had been milking 35 cows.

After motorcycling around Scotland to find a farm – and failing – he was encouraged to come south and east by top south Norfolk farmer, 'uncle' James Alston, because land was readily available for hiring. 'In those days, farms were two a penny,' said Mr Paterson, who became only the third Norfolk farmer to be elected president of Europe's largest breed society, Holstein UK, in 2004.

The hard-working Scots started dairying and milking their own herds, typically of about 35 cows themselves.

But in 1920s Norfolk, milking cows were not kept by real farmers. This new breed of 'cowkeeper' survived while their neighbours with arable and beef cattle went out of farming. 'There was a saying that if you kept cows you were not a gentleman farmer,' said Mr Paterson.

Gradually, his father built up four herds, each of 72 cows. 'If he needed more cattle, he bought more heifers from Ayrshire because he knew some dealers who were relations of [fellow Norfolk farmer] William Donald. At that time, tuberculosis testing had started.

'We knew the manager of Norwich's co-op dairy, Mr Robertson, who was also a Scot. He often visited the farm on a Sunday afternoon and would say: I need more milk.'

But it had to be TB-free milk. 'I can just remember when we cleared out any reactors (TB infected cattle) and my dad would go to Scotland to buy a couple of truck loads of Ayrshire heifers. We carted all the milk from our dairies by lorry. It was processed and bottled into one-third of a pint bottles and delivered to all schools in Norwich by 11am.'

He and his late brother, Ian, both went to college in Scotland. When Ian returned home in the late 1940s and had married, he told his father that he would prefer to stick with Ayrshires at nearby Dilham.

'My father said: 'You'd better take a lorry and pick up the best from the other herds. But if you're going to be that keen, I'd better buy some pedigree cattle.'

'Then, it was off back to Scotland to get three truck loads of Ayrshires. And he did the same, later, with the Friesians. That's how it all started.'

Later, when his grandparents retired, they didn't want to sell the cows.

'They came down by train. Mother's brothers, Uncle Rob Alston, of Witton, North Walsham, James Alston, of Sco Ruston, and my father met the cows at North Walsham station – they picked them out in turn and so they each had a third.'

In the early days, the Scots were always tenants. Until, one day, with a modest inheritance, his father bought a little farm in Dilham. 'When he went to Norwich next week, he was told by Uncle James: 'You don't buy land. You can't get your money out if there's a collapse'.'

But it wasn't long before he started buying land – and thereby hangs another story.

Actually, Mr Paterson's showing interest had been stimulated by a visit to the London Dairy Show in 1952.

'A group from Aylsham Young Farmers' Club went on a bus trip organised by Jim Mitchell, of Blickling, with his sons,' he said.

The next day, he reported to his father, who was ill in bed. 'I said, rather cheekily: I think we've got some cows out there which are just as good.'

'My father said: 'If you really think that, go and talk to George Clare, get a couple of cows on test and see how you get on. Then the next year, in 1953, we went and won. I was just 23.'

After their first triumph with Smallburgh Brenda, which produced 13 gallons of milk in 24 hours, they returned every year until the last London show.

Mr Paterson said that the enthusiasm of his dairy team was key. 'Arthur was fantastic – he learned from his father, George and I learned from my father. Arthur was special to me and he's still living in the village.'

While showing was important, he devoted his entire career to breeding better cattle. 'We had increased the average butterfat from 3.68pc and got it up to 3.8pc. We have been running at more than 4pc recently, which for a Holstein is pretty good,' he added.

Mr Paterson recalled his final success in 1970. 'I still can't believe it. It was quite incredible. We had clicked with a really good cow, and that just stimulated the whole idea.'

That autumn, they took a team of 10 cows from both herds and won 26 prizes in milking trials, inspection, groups and progeny classes. 'We won the group of three from one owner a couple of times,' he added.

Keeping cattle has been a long-standing family tradition. 'My grandfather on my mother's side bought pedigree cattle, which were imported from Holland.'

And just 10 days ago, he discovered that another even earlier generation had won at the Highland Show with an Ayrshire.

'It looks as though it has been trickling through the family's bloodlines for a long while – maybe milk runs through our veins!'

Sadly, on October 25, they will be milking no more.