Species Difference in the Composition of Milk with Special Reference to the Northern Fur Seal

Abstract

Gross composition is given for 5 samples of milk from the northern fur seal (Callorhinus ursinus). About 50% of the milk was fat. Comparative data on fatty-acid distribution (by gas chromatography) are given for: cow, water buffalo, goat and sow. Fur seals'' milk had no fatty-acid with less than 10 C; 14.7% of the total fatty-acids were unsaturated chains in the range of 20-22 C. Reducing sugars amounted to less than 0.1%. Casein accounted for 50% of the total N. The major casein fraction appears to be [beta]-casein as shown by paper electrophoresis in the presence of 5[image] urea.