Food Biochemistry and Food Processing (2 edition)

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26 Equid Milk: Chemistry, Biochemistry and Processing 515

Table 26.12.Vitamins (mg.L−^1 ) in Equine Milk

Equine Equine Bovine

Vitamin Colostrum Milk Milk

A 0.88 0.34 0.352

D 3 0.0054 0.0032 0.0029

E 1.342 1.128 1.135

K 3 0.043 0.029 0.032

C 23.80 17.2 15.32

Source: Modified from Csapo et al. 1995. ́

of vitamin E remains unchanged throughout lactation (Table

26.12)(Csapo et al. 1995). ́

MINERALS

Macro-Elements

The levels of ash in equine and asinine milk are similar (Table

26.2) and the levels of inorganic elements are close to those

in human milk except for higher concentrations of Ca and P

(Table 26.13) (Holt and Jenness 1984). The principal salts in

equine milk are phosphates, chlorides, carbonates and citrates

of potassium, sodium, calcium and magnesium. However, there

are considerable quantitative inter-species differences in milk

salts, (Table 26.13). The concentrations of all macro-elements,

except potassium, are higher in equine and asinine milk than

in human milk but all are considerably lower than in bovine,

caprine, ovine or porcine milk. The low level of salts in equid

milk reduces renal load, making it suitable in infant nutrition.

Pieszka and Kulisa (2005) reported on the low tolerance of

equine species to imbalances in mineral concentrations in milk

post-partum; slight increases in some minerals can cause severe

deformation of teeth and bones in horses and affect metabolism

and protein synthesis.

The concentration of macro-elements in equine milk is com-

parable to that in zebra milk (Equus zebra), whereas in early

lactation, the concentrations of calcium and phosphate are con-

siderably higher in domestic horse milk (Equus caballus)(Table

26.14) than in zebra milk (Schryver et al. 1986). The concentra-

tions of macro-elements in equine milk are strongly influenced

Table 26.13.Total Concentrations of Inorganic Elements (mmol.L−^1 ) and Citrate in the Milk of Eight Different Species

Species Calcium Magnesium Sodium Potassium

Phosphorus

(Inorganic) Citrate Chloride

Horse 16.5 1.6 5.7 11.9 6.7 3.1 6.6

Cow 29.4 5.1 24.2 34.7 20.9 9.2 30.2

Man 7.8 1.1 5.0 16.5 2.5 2.8 6.2

Goat 23.1 5.0 20.5 46.6 15.6 5.4 34.2

Sheep 56.8 9.0 20.5 31.7 39.7 4.9 17.0

Pig 104.1 9.6 14.4 31.4 51.2 8.9 28.7

Rat 80.4 8.8 38.3 43.6 93.3 0.06 36.1

Rabbit 214.4 19.5 83.7 89.5 54.2 17.4 80.0

Source: Modified from Holt and Jenness 1984.

Table 26.14.Concentration of Inorganic Elements (μg.g−^1 Whole Milk) in Early and Late Lactation Milk of Various

Equid Species

Species Total Solids Ash Ca P Mg Na K Cu Zn Fe

Early Lactation

Przewalski horse 11.6 0.58 1380 790 104 220 590 0.42 4.1 1.3

Hartmann’s zebra 11.3 0.50 1100 800 120 290 590 1.13 2.4 1.1

Domestic horse 11.6 0.58 1327 884 102 198 655 0.64 2.7 0.37

Domestic pony 9.6 0.48 1036 600 70 189 483 0.26 1.8 –

Late Lactation

Przewalski horse 10.3 0.33 804 419 62 137 344 0.23 1.9 1.1

Hartmann’s zebra 10.0 0.32 840 550 80 200 422 0.26 1.9 3.6

Grant’s zebra 10.7 0.35 690 490 93 277 187 1.0 2.9 2.2

Domestic horse 10.2 0.36 811 566 53 140 410 0.25 1.9 0.27

Domestic pony 9.4 0.36 857 418 77 127 250 0.37 1.7 –

Source: Modified from Schryver et al. 1986.