Renal functions and urea handling in pregnant and lactating Corriedale ewes

Abstract

Renal urea conservation was evaluated in Corriedale ewes during late pregnancy and lactation Glomerular filtration, renal plasma flow and urea clearance were significantly reduced during both states compared with control sheep. Filtered load of urea and urine urea elimination were significantly reduced only during lactation (-46% and -45%, respectively, vs. controls). No changes were noted in fractional excretion of urea. Therefore, Corriedale ewes restrict urine urea losses during lactation by reducing glomerular filtration. During late pregnancy, urea sparing is less marked.