Abstract
The effects of a natural imbalanced diet on body maturity and brain composition of rats' offspring were studied from birth over the suckling period. Results were compared with those of a group of pups from mothers fed on a low protein diet and with pups from normal rats fed on a stock diet. Chemical maturity was measured as N/H2O ratio. Pups from mothers fed on the imbalanced diet showed retarded chemical maturity at the time of birth and until 14 days of age in spite of growth progress; they grew without increasing in chemical maturity but approached the chemical maturity of controls at 30 days of age. The chemical maturity of the low-protein progeny was preserved in spite of severe growth arrest. Brain/body ratio was normal in both groups and was not correlated with chemical maturity during the perinatal period, as would be normal. In the brain, low weight, low lipids and a DNA concentration higher than normal were the characteristics of the pups of the imbalanced group from birth until 14 days of age but, at 30 days, brain composition was normal, although it weighed less than it should have done. The brain of the progeny from the low-protein group showed low weight, low lipids and protein, and the protein/DNA ratio was significantly lower until 9 days of age. At 14 days of age there remained severe growth arrest although the brain composition was approaching normal. There was a high mortality in this group and it was impossible to continue the experiment over the 30-day period. These findings confirm that if the mothers are fed on an essential amino acidimbalanced diet the brain and chemical maturity of the pups during the suckling period are affected in a different way when compared with low protein exposure, and confirmed the working hypothesis that protein quality plays a key role in development and that the effects of imbalanced diets cannot be merely ascribed to a relative protein deficiency.
