Equine whey proteins

1. 1. Zone electrophoretic patterns of milk samples have been examined from 713 mares, and classified in terms of 5 anodic zones and 1 cathodic zone at pH 8.5 (NaOHH 3 BO 3 ). 2. 2. Zone 1 protein exhibits genetic polymorphism, there being 5 variants, designated A–E. Zone 2 protein is the dominant whey protein and is designated a β-lactoglobulin. Zone 3 protein is equine serum albumin. Zone 4 contains equine α-lactalbumin and iron binding protein (probably transferrin). Zone 5 contains iron binding protein, probably lactoferrin. The cathodic zone 6 contains equine lysozyme. 3. 3. Methods of isolation and properties of these proteins are described and discussed. In particular, the amino acid sequence of the first 40 residues of equine β-lactoglobulin is compared with the corresponding sequences of the porcine and bovine proteins. The reason for the failure of peptide mapping to reveal the homology of the equine protein with other β-lactoglobulins is discussed.