[show abstract][hide abstract] ABSTRACT: 2005. Milk production and milk composition of dairy cows fed Lac100 ® or whole flaxseed. Can. J. Anim. Sci. 85: 413–416. Cows were fed whole flaxseed or calcium salts of soybean oil as a fat source. Cows fed flaxseed had lower (P < 0.01) milk yield and higher (P < 0.01) percentages of fat and protein than cows fed calcium salts. Feeding whole flaxseed and calcium salts of soy-bean oil increased, respectively, the concentrations of alpha-linolenic acid and conjugated linoleic acid in milk.