Protein malnutrition affects the growth trajectories of the craniofacial skeleton in rats

Jeffrey P. Miller, Rebecca Z. German

Research output: Contribution to journalArticlepeer-review


To investigate the effects of protein malnutrition on a normal growth trajectory, we radiographed Rattus norvegicus from 22 d (weaning) and continuing past adult size. We took measurements from longitudinal radiographs of rats fed a control diet and littermates fed an isocaloric low protein experimental diet. A Gompertz model was fit to each individual rat for body weight and 22 measurements of the craniofacial skeleton, producing parameters that described the rate and timing of growth. We tested for differences in these parameters due to diet, sex and litter with a mixed- model three-way ANOVA. Allometric analysis examined the scaling relationships between and within various regions of the skull. For most measurements, final sizes predicted by the model were not significantly different between rats fed the two diets, although the differences in final measurements showed small, but significant differences in growth between rats in the two diet groups. The instantaneous initial rate of growth, maximum rate of growth and deceleration of growth were significantly higher in the control rats for every measurement. Rats fed the low protein diet grew for a significantly longer period of time. The shape of the neurocranium was relatively conserved between diet groups; however, rats fed the low protein diet had shorter and relatively wider skulls than the controls. These results suggest that functional demands of the viscerocranium were greater after birth, and that growth in this area was faster. The viscerocranium reached functional adult proportions earlier and was therefore more susceptible to epigenetic perturbations such as dietary protein level. Protein malnutrition did not affect many aspects of adult size, but strongly altered the growth trajectory to achieve that size.

Original languageEnglish (US)
Pages (from-to)2061-2069
Number of pages9
JournalJournal of Nutrition
Issue number11
StatePublished - 1999
Externally publishedYes


  • Craniofacial
  • Protein malnutrition
  • Rats
  • Sexual dimorphism
  • Skeleton

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Food Science


Dive into the research topics of 'Protein malnutrition affects the growth trajectories of the craniofacial skeleton in rats'. Together they form a unique fingerprint.

Cite this