A NEW study on whether milk production is affected by halving the carbon footprint of dairy cow diets is being carried out at Duchy College. 

Mole Valley Farmers is running the study at the Cornwall college, to look at how milk constituents and finances are affected by the change in diet. 

There are 140 dairy cows at Duchy College’s Future Farm in Stoke Climsland, which have been enrolled on the study. The cows at the unit, which is one of Mole Valley Farmers 'Focus farms', will have two different diets and their performances on each will be compared. 

The two diets are: 

The standard diet

  • A traditional UK diet, with higher fibre and lower starch levels
  • Includes 32kg fresh weight per head per day grass silage and 10kg wholecrop
  • Fed with a meal including soya
  • 17.5% crude protein in total diet

The low carbon footprint diet (LCFP)

  • High starch, low fibre ration
  • Includes 25kg fresh weight per head per day of maize silage (which has a lower carbon footprint than grass silage), 10kg wholecrop and 7.5kg grass silage.
  • Balanced with a non soya meal, which includes prairie meal, beans and British grown rumen-protected rape seed.
  • 16.5% crude protein in total diet
  • Supplementary methionine and lysine to balance the amino acid profile and raise protein efficiencies.

Both diets are balanced with a Climate Positive Agriculture no soya, no palm, 14% crude protein parlour concentrate. 

A spokesperson from Mole Valley Farmers said: "One of the aims of the study is to show it is possible to achieve high yields and milk quality without the use of soya and its potential negative impact on the environment.

"The no soya, LCFP has been formulated using Mole Valley Farmers’ Precision Nutrition software to deliver a 5-10% reduction in methane production, a 17% increase in protein efficiency and a 50% theoretical reduction in dietary carbon footprint. This is all whilst delivering 42 litres a cow a day."

The college's herd calves in a autumn block and so 70 animals joined each study group immediately post-calving. 

The cows will be fed the diets for 100 days and will be monitered on the following: milk quality, cow weight, body condition, fertility and blood profiles. The study will also look at group feed intakes and refusals.  

The unit at Duchy College enables the cows to be split and fed differently using an automated robotic feeding system. 

Results of the study are expected in the spring of 2024.