Distribution of Milk Fat Globules in Cows’ Milk High in Linoleic Acid

The influence of feeding cows formaldehyde-treated polyunsaturated oilseed supplement on fatty acid composition and distribution of particle size of milk fat globules has been studied. Supplement increased linoleic acid in milk fat from 1.7 to 27.4%. Distributions of particle size measured by a Coulter counter showed that milk fat from cows receiving supplement had larger milk fat globules than those in milk fat of the same cows when supplementation was discontinued. However, this difference in size could not be attributed to percent linoleic acid in the milk fat since correction of the data of supplemented cows for percent milk fat and size of milk fat globules resulted in particle distributions strikingly similar in shape.