Research Finds Value in Fatty Acid Supplementation for Fresh Cows


Fat is an integral part of the fresh cow’s ration. Moreover, it is actually the fatty acids, building blocks which constitute the macronutrient, that are important in the ration.

Current research is giving exciting and promising science about the true impact of these powerful little molecules and how we can best utilize them in dairy cow diets.

New research data from Michigan State University has found fresh cows getting a blended fatty acid supplement with a strategic palmitic-to-oleic-acid ratio not only improved milk production, but the cows also didn’t lose body condition. These findings were presented by Volac Wilmar Feed Ingredients on a virtual panel held Aug. 6.

Understanding fatty acid nutrition

In opening statements, Dr. Richard Kirkland, global technical manager for Volac, explained dairy cows don’t need fats; they need fatty acids, which are some of the simplest molecules in nutrition.

In most feed ingredients found throughout the world, actual fat content tends to be quite low. This means most fats found in dairy diets are supplemented, usually containing anywhere from 84% to 100% fat. The five main fatty acids found in these diets are palmitic acid, stearic acid, oleic acid, linoleic acid and linolenic acid.

“What we have to remember when we are looking at fatty acid nutrients of dairy cows is that we must feed protected fatty acids,” Kirkland stressed. “If we look at the effect of simply feeding rapeseed oil, fish oil, soya oil, etc., we will end up with very negative effects in the rumen.”

Unprotected fatty acid prevents proper fiber digestion in the rumen and kills the good bacteria in the gut. An alternative is to use calcium salt forms of rumen-protected fats, which was used in the study. Besides being good for the rumen, calcium salt supplements also deliver these unsaturated fatty acids directly to the small intestine, where they can be directly digested and utilized by the cow.

Importance of ratios

Dr. Adam Lock from Michigan State University explained what makes all the difference in the fatty acids of dry cow diets – the ratio of fatty acid types. Specifically, in their research, this was a 60-to-30 ratio of palmitic (C16:0) and oleic (C18:1) acids in Mega-Max, a rumen-protected calcium salt fat supplement which offers greater fiber digestion and fatty absorption than other fat supplements.

“I think it’s important to remember that many commercial products that have been out the last 20 to 30 years simply took byproducts from other industries, like we do in the dairy industry very well, and utilized those as fat supplements,” said Lock. “Now we’re starting to actually make products with specific fatty acids because we’re starting to understand cows differently based on what fatty acid you’re providing them.”

In the study, one group of cows were offered a ration supplemented with Mega-Max, while a control group was not supplemented from calving to 24 days post-fresh. For the purposes of this study, this is referred to as the “fresh period.” For days 25 through 67 in milk, the groups were then subdivided into additional groups that either continued Mega-Max or were not supplemented. This next amount of time is what the study refers to as the “peak period.”

In the fresh period, Lock noted both the control and supplemented animals maintained similar body conditions.

“However, the fat-supplemented group saw notable increases in milk fat percentage and yield, resulting in 3.1 kilograms [6.8 pounds] more energy-corrected milk than the control group,” Lock noted.

During the peak period, the cows who were previously supplemented in the fresh period not only had no effect on dry matter intake (DMI), they also increased their milk output by 11 pounds per day. They also increased their milkfat by 0.2%. Milkfat yield went up from nearly 4 pounds to 4.5 pounds in groups that were previously control and fat-supplemented in the fresh period, respectively.

“Importantly, absolutely nothing on bodyweight changed,” Lock said. “Even though we saw milk increases in both the fresh and peak periods, they did not lose any bodyweight, which I think is the key. If we can get these fatty acid blends in our supplements correct, we can get the best of both worlds where we can get yield and milk components without sacrificing bodyweight.”

Delivering the benefits through lactation

Overall, this study provides insight to how a proper fatty acid profile fed during the fresh and peak lactation periods can increase production without causing a negative energy balance in the cow. It also opens new avenues for further research as well as opportunities to continue to manage fatty acid feedings through the lactation.

Dr. John Newbold from Scotland’s Rural College weighed in with his concluding thoughts from the research.

“If there’s no change in bodyweight loss, where is that extra milk coming from? We know from other work that rumen-protected oleic acid can have a beneficial effect on fat digestibility,” he said. “Not only is that 18:1 (oleic acid) itself highly digestible, by providing that oleic acid to the small intestine we can improve the digestibility, the amount of fat absorbed from the saturated fatty acids arriving at the small intestine.”

Additionally, he noted providing more oleic acid to the ovary can be beneficial for embryonic development.

With the information presented in the research, Newbold was also able to propose some solutions for formulating rations to maintain desired performance and body condition later in lactation in light of the oleic-palmitic acid ratio.

“Our recommendation is that early in lactation, we keep this ratio fairly low – in other words, hold back on the palmitic, boost the oleic in order to get this balance so we get some milk production response when we are pushing the mobilization of body reserves,” he explained.

In the mid-lactation period beyond the peak period observed in the study, Newbold noted there is an argument to push the palmitic acid ratio higher to get more milk production. This is because at this point in production, the cow will put that acid more towards the production of milk and milkfat.

This raises questions about what happens when the animal moves into the late lactation and if the continued ratio of palmitic acid runs a risk of her becoming too fat in some herds. However, this has not yet been illustrated experimentally.

“My conclusion looking at Adam’s data is that this new data as presented today are at least consistent with this picture here,” he said. “Keep that ratio low, hold back on the C16:0, push that oleic acid at least until you get in peak lactation to get the benefits of more production without the increased use of body fat.” 

Adapted from Jaclyn Krymowski for Progressive Dairy, October 2020


Tags: Feeding Strategies; Transition Cows