Short Communication: Clot contact and temperature: Key factors in serum biochemical changes of rainbow trout (Oncorhynchus mykiss)

Temperature and serum separation time from the clot can substantially influence specific biochemical components in fish blood samples. This study aimed to determine the longest permissible clot-contact duration and the most suitable temperature that exerts the least impact on serum biochemical parameters in rainbow trout (Oncorhynchus mykiss). Blood samples were stored under two temperature conditions, ۴°C (refrigeration) and ۲۳±۲°C (laboratory ambient), alongside a freshly processed control group for ۲, ۸, and ۲۴ hours. Following each storage interval, the samples were centrifuged, the serum was separated from the clot, and the following biochemical parameters were measured: total protein, albumin, globulin, glucose, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP). Up to ۸ hours, total protein, albumin, and globulin remained stable. After ۲۴ hours, globulin levels increased (particularly at room temperature) relative to the control group, although this change did not reach statistical significance (P>۰.۰۵). ALT and AST showed a downward trend from the outset; notably, ALT changes became statistically significant at ۸ hours under room-temperature conditions (P<۰.۰۵). AST alterations were significant at ۲ hours in the room-temperature group and ۸ hours in the refrigerated group (P<۰.۰۵). Glucose, identified as the most unstable metabolite, exhibited a marked but statistically non-significant decline after ۲ hours (P>۰.۰۵); however, its decrease became significant after ۸ hours at room temperature and after ۲۴ hours at both temperatures (P<۰.۰۵). These findings demonstrate that AST and glucose are highly time-sensitive indices and should be measured promptly under minimal thermal stress.

کلیدواژه ها:

Temperature ، Serum separation time ، Biochemical factors ، Rainbow trout