Dairy products are one of the major sources of conjugated linoleic acid (CLA) providing a wide range of positive health benefits in the human diet.

 A great deal of attention has been given to CLA due to its anticarcinogenic properties that include the reduction in the incidence and growth of tumors, antiobesity, enhancement of the immune system and the ability to prevent diabetes.



Dietary management of dairy cows to increase CLA in milk can be very beneficial for the consumer.

The CLA content in milk can be strongly influenced by the type of diet fed ,the breed of cows,their age as well as the type of supplements presented in the ration.Studies have shown that there is a positive effect on the CLA content in milk from pasture-based diets,however supplementing grain to cows grazing pasture decreases the CLA content of milk fat.Similarly,supplementing grain to cows fed grass silage or replacing conserved silage with corn silage lowered the CLA content of milk.

Corn silage can contain up to 50% grain reducing rumen ph and affecting microbial populations and rumen fermentation.It has been suggested that the main ruminal biohydrogenating bacteria are cellulolytic.A reduction in ruminal ph decreases the population of cellulolytic bacteria and other microbes for lipid biohdrogenation and the production of CLA and TVA.