Oxygen consumption and lactose synthesis rates of mammary gland slices from lactating guinea-pigs

The shape of the lactation curve in guinea-pigs has been studied. The peak was found to occur between days 2 and 3. The oxygen consumption and lactose synthesis rates were investigated in mammary gland slices and results expressed on both DNA and DW bases. Oxygen consumption rates on a DNA basis tended to be low at the onset of lactation and high at the peak. Lactose synthesis on a DW basis tended to decline linearly from the onset of lactation, but on a DNA basis showed a peak coinciding with that of the lactation curve. The significance of these findings has been discussed.