Constituents of platypus and echidna milk, with particular reference to the fatty acid complement of the triglycerides

Abstract

The mature milk of platypuses (Ornithorhynchus anatinus) exhibit 39· 1 g/100 g solids, of which crude lipid accounts for 22·2% crude protein 8·2%, hexose 3·3% and sialic acid 0·43% iron is in high concentration, 21·1 mgfl. Echidna (Tachyglossus aculeatus) milk is more concentrated, containing 48·9% solids, with lipid. protein, hexose and sialic acid accounting for 31 ·0, 12·4, 1· 6 and O· 70% respectively; it is even richer in iron, 33·3 mg/1. The fatty acid complement of milk triglyceride from platypuses living in their natural habitat is different from that of the echidna living in the wild: Platypus milk triglyceride contains 17·6% palmitic, 25. 2% oleic and c. 30% long-chain polyunsaturated acids, whereas that of echidnas exhibits 15· 9% palmitic, 61 ·2% oleic and only c. 7% polyunsaturated acids. The fatty acid complement of echidna milk triglyceride can be changed by altering the fatty acid complement of the dietary lipid. © 1984 ASEG.