Fatty acids are an over-looked nutrient for most classes of livestock, with no requirements listed in the current U.S. requirements for dairy cattle. But new research is shedding the light on just how important fatty acids might be, in particular for calves.

For the first time in calves, research has measured how nutrition has influenced the immune system. In a research project conducted at the Nurture Research Center of Provimi North America, calves fed a milk replacer high in linoleic acid from soy oil and soy lecithin had greater fevers after a Pasteurella vaccine than calves fed an all animal fat milk replacer.

Statistically, their average daily gain (ADG) was not changed, but it tended to be lower than calves not fed an all animal fat milk replacer. Calf ADG, starter intake, feed efficiency, hip width change and serum titers to bovine viral diarrhea and parainfluenza 3 vaccines were greater in calves fed a milk replacer with NeoTec4, a blend of butyric acid, medium chain fatty acids and linolenic acid. The rectal temperature increase after a Pasteurella vaccine was greater in calves fed the high linoleic acid diet compared with those fed all animal fat and was less in calves fed NeoTec4. While fatty acid information in dairy cattle may have been limited until now, there is a wealth of research with fatty acids for humans including requirements for infants and guidelines for consumption by adults.

In humans, specific fatty acids can alter metabolic functions such as immune functions (such as stimulating or reducing inflammation and altering titers to vaccines), alter gut absorptive tissue, influence reproduction, and act as natural anti-bacterials or anti-virals.

In animals, specific fatty acids with metabolic properties include butyrate (a short chain fatty acid), a group called medium chain fatty acids, and linoleic and linolenic acids (the two essential fatty acids in the diet). Linoleic acid (C18:2) is an essential fatty acid that causes inflammation and is naturally high in milk replacer and starter/grower diets. It is high in soy and corn. Linolenic acid (C18:3), an essential fatty acid that has anti-inflammatory and other immune-related properties and is very low in many common feeds.

Additionally, short and medium chain fatty acids (which have immune related and gut development properties) are low in most feeds. NeoTec4 is a cost-effective blend of specific fatty acids. There are 17 peer-reviewed experiments in dairy calves published and eight journal articles showing the effectiveness of these fatty acids and this specific blend in milk replacers and starter and grower feeds. The take-home message is this: Calf milk replacers are naturally high in linoleic acid and naturally low in short and medium chain fatty acids and linolenic acid. Adding more linoleic acid, an inflammatory fatty acid, was not beneficial. However, adding short, medium, and linolenic acid was beneficial to increase calf ADG, starter intake, feed efficiency, hip width change, serum titers to typical vaccines, and reduce fever.