By Debbie James

Calving heifer replacements at 22 months is helping a Pembrokeshire dairy farm reduce its carbon footprint from milk production.

Lowering the age at first calving makes good economic sense for Jeff and Sarah Wheeler but it also means that less methane is emitted during rearing when animals are consuming inputs and not producing milk.

By targeting fast early growth rates, the 35 heifers reared annually at Clyngwyn, Efailwen, calve down at 22 months.

Age at first calving was identified as having a positive influence on the farm’s carbon footprint during its recent audit as a supplier to the Tesco Cheese Group (TCG) through First Milk.

The audit showed that the business produces 983g CO2/kg fat and protein corrected milk (FPCM) – well below the group average of 1,244.

The Wheelers hadn’t set out to make carbon reduction a primary goal in their strategies for animal health planning, grazing management and woodland management but they have achieved that by default while making the business more sustainable and profitable.

The couple were producing milk from pedigree Holstein Friesians but six years ago embarked on a cross-breeding programme to produce robust smaller cows.

They looked at a range of breeds to find the one whose traits best complemented their own herd and system before settling on a Norwegian Red.

Those crossbreds are now being served to a Montbéliarde or a Fleckvieh.

Since they started their cross-breeding programme, fertility has improved in the 150-cow herd and, at under 100,000 cells/ml, the herd is achieving its lowest ever cell counts.

Cows are healthier so fewer antibiotics are used – in 2020, 75 per cent of the herd was dried off with teat sealant only.

The herd’s average milk yield is just under 7,000 litres at 4.43 per cent butterfat and 3.56 per cent protein using 1.9 tonnes of concentrates.

The crosses have fitted in well as the farm has moved towards late spring calving – cows calve from the third week of March to June with heifers calving earlier, in a three-week block from the end of January.

Milk recording is carried out every eight weeks so the cows which don’t need selective dry cow therapy (SDCT) at drying off can be identified – these are cows with cell counts lower than 200,000 cells/ml, that haven’t had a case of mastitis and don’t have teat end damage.

In the first year of using this approach, half the herd was dried off with sealant only but in 2020 it was 75 per cent.

Strict hygienic protocols are observed at drying off.

Cows are returned to the parlour after milking and the teats are cleaned and a teat dip applied. Surgical spirit is applied with cotton wool and either teat sealant or SDCT is given. Teats are dipped again and the cows are kept in the yard on silage for an hour before they are turned back into the cubicles.

No cake is fed in the two weeks prior to drying off and lime is applied to the sawdust bedding in the cubicles.

“No-one wants to lose a cow at drying off so we put a lot of effort into getting it right,’’ says Sarah.

Active woodland management is also helping to offset carbon emissions from the farm.

A 40-acre broadleaf woodland of mainly oak, ash and beech had been untouched for decades but, with advice and support from Farming Connect woodland mentor Neil Stoddard, the Wheelers have transformed this previously deteriorating asset with remedial works including tree thinning.

“The woodland hadn’t been thinned for 50 years,’’ says Jeff. “Neil helped me with the felling licence and put me in touch with the contractors who paid for the wood.’’

Analysing their operation’s carbon footprint has been a useful exercise for the Wheelers – the biggest wins have come from the measures that help them raise livestock while minimising methane emissions – but they believe farmers should be given carbon credits for hedges and woodland.

Measuring and auditing how much carbon is being stored on farmland must be found, they say, because while farming generates greenhouse gas, it can also store carbon dioxide in soils, trees, and plants.

There is currently no policy framework to count on-farm carbon storage, or to give farmers credit for such initiatives.