PO4 (Phosphate, inorganic)

Serum or heparin plasma 0.5 ml;
Reptiles: heparin plasma or serum 0.2 ml

Photometry

Reporting of results on the day the sample is received (Mon–Sat)

• Young animals physiologically have higher concentrations than adult animals.
• Hyperphosphataemia is simulated in haemolytic samples.
• The most common causes of pathologically elevated serum concentrations are kidney disease (although hyperphosphataemia is rare in horses – hypophosphataemia is more common) and hyperthyroidism in cats.
• Reptiles: The Ca/P ratio should be approximately 2:1.
• Cattle: Apart from trauma and muscle damage, hypophosphataemia is the most important differential diagnosis of so-called “atypical milk fever” (recumbency not due to hypocalcaemia).