New research from Michigan State University, US, demonstrates significant improvements in cow productivity with specific fatty acid supplementation through early lactation.

The concept of feeding fat in dairy rations is nothing new – the energy-dense nutrient is hugely beneficial to meeting increased nutritional requirements as cows simultaneously produce milk while maintaining body condition ahead of breeding.

Something that is new, however, is the developing science which continues to improve our knowledge on the roles of different fatty acids on animal performance.

According to Dr. Richard Kirkland, global technical manager for Volac Wilmar Feed Ingredients, research findings present dairy producers with opportunities to target specific fatty acid blends according to requirements on individual farms.

“Data indicate key roles for palmitic [C16:0] and oleic [C18:1] fatty acids at different stages of lactation and depending on requirements at farm level,” says Dr. Kirkland.

“C16:0 is very beneficial in improving milk fat production and yield, but it is now clear that this may be at the expense of body condition and weight loss in early lactation, the knock-on effects of which may include poor fertility.

In contrast, delivering C18:1 to the small intestine, achieved by supplementing with rumen-protected calcium salts, improves total fat digestibility and can enhance fertility through improved egg and embryo development.

“Unlike C16:0, C18:1 helps partition nutrients toward body fat stores, reducing body condition loss in the critical early lactation period.”

The importance of C16:0 to C18:1 ratio

In a recent study presented at the American Dairy Science Conference in June 2020, Prof. Adam Lock’s group from the Department of Animal Science, Michigan State University, evaluated the response to Mega-Max, a rumen-protected fat supplement containing a 60:30 ratio of C16:0 to C18:1 on cow performance from calving through early lactation.

There’s a long-standing industry dogma that fat shouldn’t be fed to fresh cows as body fat is also being mobilised to provide energy.

“However, findings from our previous research indicated this needs to be challenged and is something that needed to be analysed further,” explained Prof. Lock.

During the study, dairy cows were offered a control ration with or without supplementation with the Mega-Max calcium salt formulation from calving until 24 days in milk.

From days 25-67 in-milk, each group was further subdivided into control or Mega-Max-supplemented rations.

“Throughout the fresh period [days one to 24 in milk], control and fat supplemented cows maintained similar body condition,” explained Prof. Lock.

However, the fat supplemented group saw notable increases in milk fat percentage and yield, resulting in 3.1kg more energy-corrected milk than the control group.

“Supplementing cows in the fresh period and then throughout the peak period [days 25-67 in milk], had no effect on dry matter intake but increased milk yield by 5.1kg/day and milk fat content by 0.2%.

“This led to a significant increase in milk fat yield from 1.76kg to 2.07kg/day in control and fat-supplemented treatments, respectively. Crucially, this was achieved without increased loss of body weight or condition score.”