Stereological estimation of the absolute number of glomeruli in the kidneys of lambs

An association between the arrest of renal development and intra-uterine growth retardation (IUGR) has been demonstrated in human brings and it has been suggested that the same defect may occur in the kidneys of lambs affected by IUGR. Using design-based stereological methods, the physical disector and Cavalieri's principle, smaller absolute numbers of glomeruli were found in all six IUGR lambs studied with a low birthweight and in two of six control lambs studied with a normal birthweight than in other lambs with a normal birthweight. There was no difference in absolute numbers of glomeruli between twin births and singletons. The absolute numbers of glomeruli in three stillborn lambs were distributed among results obtained from the normal and IUGR lambs in accordance with their individual bodyweights. IUGR had a profound detrimental effect on the renal development of the lambs.