CHANGES IN THE ION CONTENT OF MILK DURING LACTATION IN THE RAT

1. 1. The relationship between total carbohydrate concentration and sodium, potassium, chloride. phosphate, calcium and magnesium content of rat milk has been investigated during the first three lactations of a group of rats. 2. 2. During each of the lactations studied the increase in total carbohydrate concentration was negatively correlated with changes in potassium, sodium and phosphate concentrations. However, no such correlations were obtained between changes in carbohydrate concentration and calcium, magnesium or chloride content of milk. 3. 3. The results are discussed in relation to species differences of milk composition. © 1979.