Threshold Time to Onset Serum Biochemical Changes of Turkoman Racehorses at Different Serum-Clot Contact Times and Temperatures

BACKGROUND: To minimize the effect of time and temperature on some serum biochemical parameters determine stability limits of each analyte in precentrifuged blood samples is essential.OBJECTIVITIES: This study aimed to investigate stability limits of 10 analytes in blood samples of Turkoman racehorse stored in different temperatures and times. METHODS: whole blood samples from healthy horses (n=10) were stored for 2 h (baseline), 6, 12, 24, and 48 h at 25 ˚C or 4 ˚C. Commercial kits (Parsazmoon, Tehran, Iran) were used to sample analysis. RESULTS: Albumin (ALB), total bilirubin (TB), and phosphorous (P), exhibited remarkable changes at 25 ˚C. Storage time had no significant effects on urea, total protein (TP), lactate dehydrogenase (LDH), creatinine, and alkaline phosphatase (ALP) at 25 ˚C for as long as 12 h. The stability of alanine transaminase (ALT) in serum stored at 25 ˚C was 24 h and at 4 ˚C was 48 h such as LDH. Aspartate transaminase (AST) was the most unstable analytes at different storage times at both temperatures. Urea, TP, ALB, TB, and P were stable at 4 ˚C for as long as 6 h. Creatinine and ALP were affected by 24 and 48 h storage time at both temperatures. There was a significant difference (p <0.05) in AST and ALT activities between two temperatures. There was no significant difference in creatinine, urea, and TB concentrations between two storage temperatures at any of the storage times.CONCLUSIONS: This study showed that some analytes have acceptable stability in clotted blood samples that were stored at 4 ° C for 6 h.