Abstract :
We have studied the fetal programming of lambs born to ewes exposed to high salt during
pregnancy. In the present study, we hypothesise that salt-programmed lambs may not
need to drink as much saline water as control lambs and that voluntary feed intake of
salt-programmed lambs would be reduced. We used two groups of lambs born to ewes fed
either a high salt (13% NaCl) diet during pregnancy (S-lambs; n = 12) or control animals born
to ewes fed a conventional (0.5% NaCl) diet during pregnancy (C-lambs; n = 12). Animals
were offered ad libitum amounts of saline drinking water containing 1.5% NaCl for 2 days.
Results indicated that there was a significant difference between fetal origin of the lamb
(i.e. between C and S-lambs) and time (day 1 and 2) on water intake (P = 0.055), urinary
output (P = 0.002), and sodium excretion (P = 0.002). There was an interaction between fetal
origin of the lambs and time (day 1 and 2) on the area under the curve (AUC) for the
plasma concentration of aldosterone (P = 0.017). Aldosterone concentration for C-lambs
ranged from 167 to 196 pg/ml over days 1 and 2, whilst S-lambs reduced their aldosterone
by two-thirds from day 1 to 2, from 214±24 to 74±8 pg/ml. A novel result was a marked
difference in feed intake between C and S-lambs, where S-lambs consumed approximately
0.5 kg DM/day (35%) less than C-lambs which was associated with a decrease in insulin
secretion with time in both S and C-lambs. In conclusion, feeding a high salt diet to pregnant
ewes affected the physiological responses of their offspring to the consumption of saline
water during a period of 2 days illustrating that fetal programming changed the temporal
pattern of how the offspring adapt to a load of ingested salt.
