The responses of goats to the experimental induction of hypocalcaemia with cation-exchange columns.
1. Ionic calcium was selectively removed from the circulating blood of three anaesthetized goats by means of columns of cation-exchange resin. Concentrations of other ions were not directly affected by the column.2. A calcium extraction rate of 0.35 m-equiv/min caused a fall in plasma total calcium of up to 40% in 35 min. Plasma calcium concentration returned to normal within 2 hr of the end of calcium removal.3. Mobilization rates reached a maximum between 15 and 20 min after calcium removal commenced, declining rapidly after it had stopped.4. Removal of calcium by EDTA infusion results in a similar calcium mobilization pattern to that produced by Ca removal by ion-exchange.5. A smaller variation appears to exist between goats in maximum calcium mobilization rates than in maximum phosphorus mobilization rates and goats may be able to mobilize phosphorus relatively faster than calcium.
Symonds
H W
HW
Treacher
R J
RJ