Jan and Ivo sell their milk to Friesland Campina and receive an average 36.5 cents per litre including taxes. Ivo estimates his costs, including farm labour for him and his father, at 34.5 cents per litre.
With so many cows, the Netherlands has to comply with EU regulations that govern the amount of phosphates that can be used per farm with a base figure taken from stocking rates in 2015.
Some Dutch dairy farmers are being forced to move their young stock to other farms in different European countries in order to spread the phosphates quota restriction and comply with the regulations.
Jan and Ivo send half their young stock to a farm in Belgium, close to the French border, to be contract reared in order to comply with their phosphates quota.
"We currently have 84 animals in Belgium," says Ivo. "We send them out there from eight months to one year old and bring them home two months ahead of calving. Some of them are sold in Belgium before we need to bring them back and we sell them for around €1,500 freshly calved.
"The phosphates regulations from the European Commission make it very hard for a young farmer to expand. Land here is around €70,000 per hectare. We operate around 100 hectares here for growing grass and crops but need more.
"I think there needs to be a new system introduced that allows farmers to invest in slurry separation equipment so we can reduce the phosphates applications.
"The challenge we face today as dairy farmers is achieving a return on our investments whether it be in infrastructure, land or indeed on an animal health plan."
The first free-stall barn on the farm was built in 1979 and they expanded in 1988 and again in 2005 to 135 cubicles. Two years ago a brand new free-stall barn with another 125 cubicles was added.
Two Lely robotic milking systems have been in the first barn since 2005 and another two secondhand robots were added to the new barn in 2016.
"The new barn cost us around €6,000 per cow place including the price of the robots," said Ivo. "We keep the older cows in the new barn as it has extra comfort for them. The cubicles in all the barns are deep filled with a mix of one kilogram of straw, two kgs of water and three kgs of lime.
"Good ventilation and available light are also important to our herd and we must allow them outdoors in the summer time for six hours per day for 120 days."
In order to sell stock, the Hermanussen family must maintain a herd with high health status and also try to reduce their use of antibiotics on the cattle.
Ivo adds: "Animal health is very important to us and we see continued use of antibiotics as unviable. On this farm we operate a strict animal health and treatment plan.
"Each time a cow has a problem she is assessed and we closely follow the regulations on how to treat her and with which specific medication.
"We focus more on prevention rather than treatments to improve animal health and vaccinate for IBR, BVD, Lepto and Salmonella. Hygiene and cleanliness are also very important factors in our efforts to maintain a healthy herd."
Since 2010 the Hermanussen family have reduced their bills for antibiotics down by 25 per cent thanks to their animal health programme. Plus, the farm now spends around 30 per cent of its health plan budget on prevention rather than treatments.
"Following our strict health plan has made us realise that the use of antibiotics on every animal is not necessary. At the moment we are down to using antibiotics on only half the herd which on average means we have reduced antibiotic use by two animal doses per day," he says.