Milk Content from Cows Fed Different Diets

Background and Methodology
Conjugated linoleic acid (CLA) occurs naturally in foods, but the principal dietary sources are dairy products and other foods derived from ruminant animals. CLA has been shown to have anticarcinogenic properties. Some studies have suggested that the CLA content of milk could be increased through manipulating a cow’s diet. The nutritional and management factors that influence the CLA content of milk have not been studied extensively. This study determined the CLA content of milk managed under different dietary regimens. Four experiments were conducted in order to achieve the objectives of the study.

Findings
Results from the experiments showed that CLA content of cow’s milk fat can be increased through different nutritional management practices. Supplying additional 1% fat in the diet through high oil corn and high oil corn silage did not influence CLA content of milk. Increasing the proportion of grazed grass from pasture in the diet of dairy cows linearly increased the CLA content of milk. Cows grazing permanent natural pasture had 500% more CLA. Feeding pasture grass in dry form as hay did not affect CLA content.

Reference:
Dhiman, T. R., Anand, G. R., Satter, L. D. & Pariza, M. W. (1999). Conjugated linoleic acid content of milk from cows fed different diets. J. Diary Sci. 82:2146-2156.