Get the fat balance right to boost milk performance

Additional fat supplements should be fed in equal amounts to that secreted in the milk so as to boost performance, according to research from Ohio State University, US.

Volac’s Dr Richard Kirkland says this is a good rule of thumb for feeding fat to cows in energy balance (those neither gaining or losing body condition).

This approach takes into account various aspects of fat use by the cow, including fat digestion and absorption, uptake of fatty acids by the udder and proportion of fat oxidised for energy.

“Additional studies have concluded cows supplemented with fat included at or below the recommended level responded with an increase in milk yield, milk fat yield, energy-corrected milk and energy-corrected milk per unit of dry matter (DM) intake,” says Dr Kirkland.

“In contrast, the second group of cows fed diets excessive in fat responded less; there were no significant changes in milk yield, fat yield, protein yield or energy-corrected milk compared with control, non-fat-supplemented diets.”

Other research has demonstrated maximum efficiency of milk production occurs when 15% to 20% of the metabolisable energy (ME) in the diet comes from long-chain fatty acids. For high-yielding dairy cows, the guidelines indicate fat concentrations of up to 7% to 8% of the ration DM could be required.

Dietary fat requirement based on milk fat yield (cows neither gaining or losing body condition)

Dr Kirkland adds: “Fat is one of the essential nutrients in any ration and, like others such as protein, fibre, minerals and vitamins, must be balanced in diets to ensure optimum milk production. However, consideration must also be given to the ‘type’ of fat supplement fed to ensure the fat is ‘protected’ and does not result in negative effects in the rumen.”

• Volac’s updated Fat Calculator can be used to determine a herd’s dietary fat requirements, together with the dietary fat supply based on the ingredients used.