Fourteen healthy yearling Holstein steers were used to study the influence of the levels of hemolysis and serum storage at different temperatures (4º C, -10ºC and at room temperature) on serum inorganic sulphate concentrations. The correlation of inorganic sulphate concentration between plasma and serum was also compared. Three different levels of hemolysis were obtained by adding distilled water to the blood. Precision studies were undertaken to determine the viability of the turbidimetric technique used to measure the inorganic sulphate concentration. No difference in the inorganic sulphate concentration was found between serum and plasma (p>0.91), between serum kept at different temperatures (p>0.87) and between hemolysed and normal serum (p>0.85). Increasing levels of hemolysis did not influence the serum inorganic sulphate concentration. The turbidimetric technique was suitable and accurate for routine analysis of serum inorganic sulphate. It was concluded that serum kept at room temperature can be used for practical routine surveys to assess the sulphur status in cattle.
inorganic sulphate; serum; blood tests; sulphur; cattle
