Reference values of electrolyte plasma concentrations in healthy piglets during the first 48 hours of life.

The aim of this study was to analyse the plasma concentrations of sodium (Na), magnesium (Mg), calcium (Ca), inorganic phosphate (P) and potassium (K) in mature, healthy suckling pigs during the first 2 days of life in order to obtain more detailed information about this aspect of the neonatal adaptation period. Blood samples were taken from 120 suckling piglets (30 min after birth, and then at 6, 24 and 48 h post-natum). The control group consisted of 60 piglets at the ages of 1 and 2 weeks. All electrolyte concentrations showed a significant age influence (P < 0.001). Thirty minutes post-partum a significant correlation between body temperature (T) and both Mg (P < 0.05; b = -0.13) and Ca (P < 0.05, b = -0.09) could be shown. In the sixth hour of life, there was a significant dependency between Ca (P < 0.05, b = 0.48) and body mass, whereas a relationship to sex could be established for P (P < 0.05). After the twenty-fourth hour of life, there was a significant relationship between body T and both Mg (P < 0.05, b = -2.26) and P (P < 0.05, b = -6.54), as well as between body mass and Ca (P < 0.001, b = 0.89). After the forty-eighth hour of life, statistically significant correlations between body mass and Na (P < 0.05, b = 25.72), P (P < 0.05, b = 4.92), and Ca (P < 0.001, b = 1.61) became apparent. At this point, K showed a significant dependency on T (P < 0.05, b = -0.80). It may thus be hypothesized that in the first phase following birth, disturbances in temperature regulation exert a primary influence on the level of neonatal vitality, whereas body weight becomes a deciding factor at a later point in time.