The phytanic acid content of the lipids of bovine tissues and milk.

In three steers which were given grass silage for six months, the content of phytanic acid (i.e. 3,7,11,15-tetramethyl-hexadecanoic acid) in plasma lipid increased to about 8% of the total fatty acids, whereas after this time the proportion in the total fatty acids of liver and heart lipids was about 1%, and only 0.1% in those of kidney lipids; the acid was present in trace amounts in adipose-tissue triglycerides and was apparently absent from brain lipids. In eight lactating cows which were given grass silage for about 3 months, the content of phytanic acid in the total long chain fatty acids of milk and of plasma was 0.7% and 13%, respectively. In the plasma lipids of both steers and lactating cows, phytanic acid constituted a substantial proportion of the total fatty acids of the triglycerides and phospholipids; the acid was present in lowest proportion in the cholesteryl esters.