A research trial was carried out at the University of Nottingham to determine the effect of a rumen inert palm-free fat supplement for dairy cows on milk production, milk constituents, cow health, fertility, feed conversion efficiency and potential implications for healthier milk for human consumption.

The project set out to provide a way of increasing the environmental sustainability and reducing the carbon footprint of UK dairy farming, improving the efficiency and profitability of dairy farming and enhancing the value of UK produced milk to producers, retailers and consumers. The aim was to do this by substituting commonly used fat supplements incorporating palm oil and palm oil derivatives with a combination of uniquely rumen protected fatty acids from non-palm oil or derivative sources.

The research was co-funded with CIEL and the selected research partner facility was the University of Nottingham Centre for Dairy Science Innovation, led by Professor Phil Garnsworthy UFAC developed a new palm-free fat supplement, Enviro-lac, manufactured from locally sourced vegetable oils together with fish oils. Before use in the research trial, Enviro-lac was tested for palatability on several commercial farms and found to be consumed readily.

Enviro-lac was incorporated into the Partial Mixed Ration (PMR) fed to the cows ad libitum at a rate of 0.5 kg/day. For the Control diet, the rumen-inert fat was Megalac, based on palm oil, fed at 0.5 kg/day. Cows were more efficient in feed utilisation when fed on Enviro-lac, the new fat supplement. It increased milk yield (+0.6kg/d), fat (+0.16%) and protein (+0.05%) concentrations with no difference in dry matter intake.

Enviro-lac increased the proportion of short and medium chain fatty acids synthesised in the mammary gland pointing towards improved rumen fermentation, leading to higher acetate production. Although the new fat supplement has a higher fibre content than Megalac, it did not increase methane emissions. Feed carbon footprint of the new fat supplement was approximately one third of the footprint of Megalac, and reduced the feed carbon footprint per kg of milk by 11%.

The reduction in carbon footprint could help to reduce land use change associated with growing palm trees. Enviro-lac contains fish oil. There is a trend towards healthier milk shown by the Milk Fatty Acid profile analysis, in particular with regards to Omega 3 DHA.