Nutrition of the milk‐fed calf

An intake of spray‐dried whole‐milk powder equivalent to 2% of body weight was maintained in calves during the first 12 weeks of life when the powder was supplemented with iron, copper, and magnesium. Intakes relative to body weight declined after the age of 12 weeks when fortification with iron and copper ceased. Gradual increases in the dry‐matter content of milk to compensate for the decline in abomasal capacity relative to body weight did not enhance intake between the age of 12 and 16 weeks. Supplementation of spray‐dried whole‐milk powder with iron and copper at levels of 46.7 and 5.1 mg/kg respectively maintained blood haemoglobin concentrations. Fortification of the powder with 0.25 g of magnesium per kg did not prevent, but appeared to delay, the onset of progressive hypomagnesaemia. An increase in the apparent digestibility of fat and a decrease in the digestibility of lactose and ash were noted with advancing age. Reconstitution rate did not affect the digestibility of milk nutrients up to the age of 16 weeks.