Animal Scientists from the University of Saskatchewan have found that supplementing a dairy cow’s diet with linPRO-R products is an effective strategy for increasing the concentration of healthy fats in bovine milk.
The human health benefits of omega-3 fatty acids are well recognized by health professionals and consumers. These fatty acids have been suggested to improve cardiovascular health, reduce inflammation and protect against certain forms of cancer. Unfortunately, the diet of most North Americans is lacking in these important nutrients. This is a problem that has been linked to the increased incidences of obesity and chronic inflammatory diseases plaguing Western society. Therefore, increasing consumer access to these nutrients could contribute to the prevention of serious human disease.
Feeding flaxseed-or any form of unsaturated fat- to cattle is complex due to the nature of the animal’s digestive system. The fat must be in a protected form to prevent digestive disturbances in the rumen; however, it must also be in a form that is easily digested in the small intestine so the fats can be incorporated into the milk. Extrusion processing is a heat treatment that can be applied to oilseeds and has been suggested to provide some protection of the unsaturated fats from the rumen environment. Other approaches include the use of whole oilseeds or the addition of tannins to the animal’s diet. These are just some examples of strategies that may increase the rumen outflow of unsaturated fats and improve the fatty acid profile of the milk. The real question; however, is how these different forms of flaxseed products compare among one another.
To helps address this issue, O&T Farms Ltd. collaborated with the University of Saskatchewan on a study that focused on project increasing the concentration of healthful fats in cow’s milk through dietary means. Additional funding was provided through the Industrial Research Assistance Program and SaskMilk. The trial was conducted at the University of Saskatchewan’s Rayner Dairy Research and Teaching Facility (Saskatoon, SK.) using unprocessed flaxseed and extruded flaxseed products as the main omega-3 source in the animal’s diets. The flaxseed products were provided by O&T Farms Ltd. and included an unprocessed flaxseed and pea product, an extruded flaxseed and pea product (commercially known as linPRO-R) and an extruded flaxseed and high-tannin faba bean product. The cows were offered either a control diet-with no flaxseed – or a diet supplemented with one of the three above mentioned flaxseed products.
The results show that the fatty acid composition of the milk was dramatically altered among the flaxseed treatments (Table 1). Conventional dairy milk in Canada only contains approximately 0.5% total omega-3 as a percentage of fatty acids. The results of this study demonstrated the ability to more than double the amount of omega-3 fatty acids recovered in the milk simply by feeding an extruded flaxseed product such as linPRO-R. In addition to the increased levels of omega-3s, results of this trial also demonstrated a three-fold increase in another human health related fatty acid, conjugated linoleic acid (CLA) as well as a decrease in the level of saturated fatty acids.
Although feeding unsaturated fats, such as those found in flaxseed, may improve the milk for consumers we must also consider the impact these feedings strategies may have on the cow. For this reason, the research included an evaluation of flaxseed products on dry matter intake (DMI), milk yield, milk composition and rumen fermentation characteristics. Dry matter intake of the animals was similar among all treatments with an average of 24.5 kg/day (Figure 1) while milk yield tended to increase with the inclusion of flaxseed in the diet, especially if that flaxseed was in an extruded form resulting in an improvement in feed efficiency from 1.68 to 1.71.
Fat corrected milk yield was maintained among treatments with an average of 40.5 kg/d and milk components were unaffected. Rumen fermentation characteristics were also evaluated with no observed differences between treatments. This suggests that feeding the extruded flaxseed products was effective in increasing healthy lipids without compromising animal performance.
The successful supplementation of flaxseed in a cow’s diet appears to largely depend on the form in which it is fed. Based on these findings, it was concluded that that feeding linPRO-R to dairy cattle is an effective strategy for increasing healthful fats in the milk without negatively impacting animal performance.
Implementation of these innovative feeding strategies has the potential to improve the health of the animal while simultaneously improving the nutritional value of milk for consumers. This farm-to-fork connection is extremely relevant at a time when the health of our farm animals and the quality of our food are of utmost importance to both producers and consumers. To read the complete M.Sc. thesis related to this study, visit the University of Saskatchewan’s e-commons webpage.
For more detailed information on this or other research projects, please contact O&T Farms Ltd.