The effects of hypocalcaemia due to a 4-hour infusion of Na2EDTA solution on various blood and urine analytes in dairy cows and a comparison of these effects between cows with high and low erythrocyte potassium concentrations

Induced Hypocalcaemia by Na2EDTA Infusion. A Review

“…In contrast, plasma potassium does change during spontaneous milk fever (Littledike et al, 1969). Similarly, lowered potassium has been found during Na 2 EDTA-induced hypocalcaemia and may remain low for several hours after infusion (Daniel, 1980;Fenwick and Daniel, 1992). An increase has been reported during infusion just prior to the paretic stage, whereafter it dropped to below initial values (Berger and Gerber, 1977;Desmecht et al, 1995).…”

“…A reduction in plasma inorganic phosphate (P in ) has been shown in spontaneous milk fever (Littledike et al, 1969) but also in experimental hypocalcaemia (Payne, 1964;Ramberg et al, 1967;Berger and Gerber, 1977;Daniel and Moodie, 1979;Fenwick and Daniel, 1992;Riond et al, 1997) where the decrease may be marginal and short-lived (Ramberg et al, 1967;Desmecht Fig. 4.…”

“…There is disagreement regarding changes in Mg during EDTA-induced hypocalcaemia. Most investigators analysed total plasma Mg and found either unaltered plasma Mg throughout the infusion period (Ramberg et al, 1967;Berger and Gerber, 1977;Daniel, 1980;Desmecht et al, 1995) or a minor increase within normal levels (Fenwick and Daniel, 1992). Although Daniel (1980) saw no significant mean changes in plasma Mg concentration among seven cows with Na 2 EDTA-induced hypocalcaemia, he found evidence that cows responded differently in terms of plasma Mg, i.e.…”

“…The typical symptoms of muscle tremor, excitation, anorexia, obstipation, lack of fore-stomach motility, ataxia, paresis and coma are all reproduced in induced hypocalcaemia. However, in the latter case certain symptoms, besides the classical ones, have 393 Induced Hypocalcaemia by Na 2 EDTA Infusion Desmecht et al (1996) bull calves/17 4.7% 1.65 ml/kg/h ---0.4820.11 yes Fenwick and Daniel (1992) been described, such as increased salivation, elevated tail and increased mouth and tongue movements (Fenwick and Daniel, 1990;Desmecht et al, 1995).…”

“…Sodium and chloride do not change during induced or spontaneous hypocalcaemia (Fenwick and Daniel, 1992;Radostits et al, 1994;Desmecht et al, 1995), although interference with the ration cation-anion balance (see below) may alter plasma chloride slightly (Abu Damir et al, 1994). In contrast, plasma potassium does change during spontaneous milk fever (Littledike et al, 1969).…”