College opts for dairy unit that is eco friendly; Farming.

Byline: Jennifer MacKenzie

SAC is updating its Acrehead dairy unit at Dumfries in a pounds 380,000 investment with the emphasis firmly on benefits to the environment and cost-cutting.

The building on the unit at Crichton Royal has been modernised to accommodate 220 cows, up to 170 of them milking, and this has included the installation of a new milking parlour which as well as dramatically reducing electricity used is also utilising recovered roof water.

Farm manager Hugh McClymont said: "When the milk price was on the floor two years ago, decisions had to be taken about the dairy business.

"We had a unit that was 'tired' and needed investment, but was still fit for purpose, so the decision was made to improve the facilities and increase cow numbers to what the facility was originally designed for."

The investment has included new cubicles, repositioning the new 24x24 50 degree herringbone parlour to allow the installation of cattle handling facilities. Work on the third phase is to comply with NVZ requirements for slurry storage.

"There are many dairy facilities in the region which were installed in the 1970s and this refurbishment shows that you can update existing units to improve cattle handling, cow flow and make other efficiencies without investing in a completely new set-up," he said.

Improvements at Acrehead will enable it to be used for additional research and trials work.

Based on the successful model of the Crichton site and with the plan to increase cow numbers at Acrehead, Hugh decided to move up to a 24x24 parlour to replace the aged 20x20.

The parlour has auto ID, backing gate and auto shedding to improved cattle handling facilities.

He said: "It includes a fully automated auto identification and milk recording system transmitting information from the milking unit to a computer, which is vital for use in research."

Another major consideration of the parlour was its ability to monitor cows' activity through a pedometer which highlights cows in oestrus and those which are unwell.

Only 16 days into the parlour being in operation the system was yielding useful information to the computer. Another essential was the Cowmander backing gate to bring the cows into the parlour which has also helped the cows adapt to the new parlour - almost immediately the twice daily milking time was at the anticipated two hours time compared with up to three hours in the former parlour.

"The acceptance by the cows to the new environment has been remarkable - even the first milking took only two hours when we were expecting it to take more than three hours."

A further benefit for the dairyman is that the parlour is virtually silent in operation, thanks to overhead stainless steel cabinets which house the ACR, pulsation lines with the new silent vacuum-on-demand pump in the refurbished plant room. The parlour's VoD system is also a key energy and cost saving feature which is expected to make up to 80% savings on purchased electricity by only generating as much vacuum as needed by quickly reacting to changing vacuum demand and regulating the speed of the vacuum pump.

Unnecessary and wasteful costs can be avoided, as well as reducing noise and wear and tear on the vacuum pump.

Future plans are for the sinking of a borehole for water supplies.

At present, rainwater from the 2,400sq m dairy building roof is being used. It is pumped through a filtration system and fed to the plate cooler and heat recovery unit. One of the two 6,000-litre milk vats is also dissipating heat through a heat pump into mains water used for plant washing.

Roof water at an ambient temperature is available for cows to drink and also for washing down the parlouryard and equipment.

All the plant and parlour washings are collected in a sump and pumped to the original slurry tower, which will be used solely for dirty water storage on completion of the new concrete slurry store for the project's third stage.

This will allow six months' storage of higher-dry-matter slurry to comply with NVZ regulations and allow better use of nutrients on the farm.

The herd at Acrehead is producing an average 8,000 litres a head of milk sales off a TMR diet during the winter and housed at 9pm during the summer to maximise grass intakes. The cows are topped up to yield in the parlour above 30 litres a day.

When the milk price was on the floor, decisions had to be taken about the dairy.

CAPTION(S):

LONG LIFE The Scottish Agricultural College decided to revamp its dairy rather than build a new one.; RESEARCH Manager Hugh McClymont.