Composition of Mares’ Milk as Compared with that of Other Species

Abstract

Summary Twenty-six samples of milk produced by one Palomino and four Percheron mares were assayed for water, protein, ascorbic acid, phosphorus, potassium, magnesium, and calcium. The milk was produced in the early lactation period during late winter and early spring months when the mares were subsisting principally upon hay and grain. The milk from the Palomino mare contained more protein, phosphorus, potassium, and magnesium than the Percheron mares' milk. The average values for the milk of the Percheron mares were: water 89.7 per cent, protein 2.3 per cent, reduced ascorbic acid 89mg. per liter, phosphorus 63mg., potassium 64mg., magnesium 9.0mg., and calcium 102mg. per 100g. These values indicate that mares' milk contains more water than cow, goat, ewe, buffalo, camel, or human milk; less protein than cow, goat, ewe, buffalo, or camel milk, but more than human milk; more ascorbic acid than cow, goat, or human milk; less phosphorus than cow or goat milk but more than human milk; only about one-third as much potassium as cow or goat milk; and less magnesium and calcium than cow or goat milk, but about four times as much calcium as human milk. The ratio of calcium and phosphorus is considerably higher in mares' milk than in cows' or goats' milk but possibly lower than in human milk.