[Effective utilization of milk proteins by rats during the neonatal period]

The assimilation of milk proteins in dynamics by rats during the first 23 days of their life was studied. During this time the animals were kept on a natural milk feeding and were denied the maternal one. Data on the amount of consumed protein and on an increase of the protein content in the carcass in 2- and 4-day long intervals served as a basis for determining the degree of effective utilization of protein (U) by rats. It is shown that the degree of the food protein, while remaining at a high level, experienced certain changes. It is possible to distinguish three periods in the change of this value: the first--starting from birth up to 5 days, with U rising from 74,5 up to 92.1 per cent, the second period, the milk diet proper,--up to the 15th day, marked by a high value of U (approximately 93 per cent) and, finally, the third period--transitional to the ration of an adult animals--marked by a drop of U down to 67.8 per cent. The data obtained may be used in considering issues related to features specific for the processes of the protein assimilationin in the early post-natal period.