Effect of graduated protein supply (0-50%) on hematologic values as well as protein and urea concentrations in the plasma of rats

Abstract

The influence of graduated protein supply (0-50% casein) on hematological values was studied in growing rats and compared with other criteria of the supply status. The following results were obtained: Weight development was found to reflect to 30%, the plasma protein content to 40% the level of protein supply. The highest protein levels revealed a trend towards lower values. At a dietary protein content of 15 to 20%, the urea concentrations of plasma went through a minimum. Both with better and with poorer protein supply they proved higher thus suggesting an increasingly energetic conversion of the feed protein. The hematological values hemoglobin, hematocrit and erythrocyt number responded uniformaly to the level of protein supply. This is also attributable to the close statsitical relationship between these three magnitudes. Whilst at the end of the experiment the erythrocyt number with protein-free diet proved lowest, the smallest values for hemoglobin and hematocrit were observed with 5% protein. From 10% on the differences were not so marked. Especially high values were measured, however, for all criteria at 40 and 50%, partly at 25% protein. As the calculation of the mean cell volume (MCV) revealed, insufficient protein supply is likely to affect rather the erythrocyt ripening than iron conversion. In agreement with this idea, the mean corpuscular hemoglobin concentration (MCHC) was not found to be influenced by protein supply.