But nothing has managed to deter them from the family business.

In fact, the fifth generation of the family is now starting to play a part in activities on the Hayes' dairy farm and if their enthusiasm is any indication, farming will be a family affair for many years to come.

The Hayes family will celebrate a century of dairy farming on their Avoca property on June 28.

Family patriarch, Colin Hayes, 73, said the 240 acre property was bought by his grandfather Walter Harrison Hayes in 1912.

In those early days Walter would milk about 20 head of cows by hand each day.

"I can remember even when I was only about five, in the early 1940s I would help with the milking," he said.

"It was still done by hand at that time and we would collect the milk in a bucket.

"We would then pour the milk through a strainer into milk cans which were kept chilled in a tank."

It wasn't until 1950 when electricity became available on the property that things began to move towards a more automated process with electric milking machines installed in the dairy.

And dairying operations have continued to expand since then.

The family worked with a 16-aside milking system for many years, but has more recently boosted this to 32-aside.

The end result is that they can now milk more cows and in much quicker time.

The introduction of automated milking also led to more careful management and processing of the milk product.

"The milk (from the cows) goes directly along the lines in the milking machine into a refrigerated vat where it is chilled below three degrees celsius," he said.

"At the end of milking the milk in the vat is treated to ensure it is of the highest quality for sale."

Technological advancements have been invaluable in enabling the family to grow their dairying business.

The family currently milks about 250 cows each day, and they have their sights set on an ultimate target of 350.

Colin is the first to admit that he never thought they would be able to "manage milking even 200 cows".

The family has learned over the years that very little is impossible or insurmountable as it has survived many challenges.

Colin said World War II and the depression of the 1940s caused a drop in demand for milk with often three days a week classed as block days where his family earned a much lower price for their product.

"I also remember struggling through flooding in the 1950s, 70s and 90s and drought in the 1980s and 2000s," he said.

The introduction of the milk quota system in the 1980s was another controversial time in the dairy industry with farmers given a quota of milk to supply each day at which they could receive a higher price. Any milk above that quota was sold at a lower price.

"If you didn't meet your quota it could be reduced the following year, but at least you could buy additional quota from other farmers who were getting out of the business," he said.

This has more recently changed to a two tiered system where there is no opportunity to buy a higher tier at which the best price can be earned.

The tiers are assessed annually and can be changed depending on the production results achieved by each farmer.

Colin said there had been a lot of changes, as far as dairying was concerned, over the past 100 years and plenty of ups and downs.

But he is quick to add that he couldn't imagine living any other life.

"It's been a real good life, fantastic," he said.

In fact it is a life that Colin continues to play an active part in, helping on the farm several days each week.

Meanwhile, his sons Evan and Stephen and their families are also embracing the life.

The brothers share the duties, each working five days with budding young fifth generation farmers, Jack, 14, Harry, 10, Jessica, 7, and Peggy, 4, never far away to help in any way they can.

The prospects of budding young dairy farmers coming through the ranks is good news for both the Hayes family and the Highlands dairying industry as a whole.

What was once a thriving industry with well over 100 dairy farms in the region has been well and truly depleted over the years.

There are currently only 17 dairy farms, including one at Mittagong and the rest in the Avoca and Kangaloon areas.