By Debbie James

Sand bedding has helped to drive mastitis levels down at a west Wales dairy farm.

The Allison family use sand to bed the cubicle stalls for the 270-cow Holstein herd housed in their USA-style cow barn at Sychpant Farm, near Cardigan.

This material offers comfort and protects udder health, says Marc Allison.

The rolling somatic cell count (SCC) is 102,000 cells/ml and the Bactoscan 11.

The sand costs around 60p per cow, per week, says Marc.

“The beds are refreshed twice a week and we have designed lanes in a way that slows down the passage of effluent when the passages are cleaned so that the dirty sand can be collected to prevent it entering the lined slurry lagoon,’’ he says.

The sand is removed with a loader four times a year and spread onto the land.

Antibiotic usage has also reduced since the new housing was commissioned.

The £300,000 building is designed to maximise exposure to natural daylight and is equipped with automatic ventilation capable of refreshing air in the entire building in just 90 seconds.

For three years in succession there have been just six cases of mastitis annually.

When they were researching new housing, the family looked at a number of natural-vent barns but were unconvinced that this solution would work for them as they rely on the stack effect to refresh the air and this is contingent upon occupancy and weather conditions.

“If there aren't enough animals in the barn, the stack-effect doesn't initiate, and strong winds will unpredictably dominate the barn environment,’’ says Tom Allison.

“We also have a lot of rain here, which often comes with wind, so we were concerned about keeping the beds dry.

“Wales had record rainfall in 2012 so we asked ourselves why would we build a new barn to mitigate against wet weather but where ventilation is compromised?’’

They decided to build a barn that would work equally well in winter or summer as this would give great flexibility to house some or all of the herd.

Marc and Tom visited farms in America to understand if a US-inspired design could work in Wales; during that visit veterinarian Dr Michael Wolf shared with them his research on ventilation, barn design and lighting levels.

Marc later designed the barn as a variation of what had been seen in the US.

Polycarbonate side cladding is treated to prevent a ‘greenhouse’ effect while allowing plenty of natural daylight.

This effect has been maximised by limiting the concrete walls at the base of the side walls to less than a metre high, sufficient to protect the cladding when the cows lunge.

The barn allows the herd to be managed as two groups which suits the three-times-a-day milking regime and allows some animals to be housed in summer if needed.

An automatic ventilation system incorporates four speed, controlled, 72-inch diameter fans above the beds so every cow place has consistent fresh air. They run faster as the temperature rises.

Even in the winter the whole volume of air in the building changes at least five times every hour.

“In the summer, we can exchange the entire volume of air in the building in 90 seconds,’’ Tom explains.