The behavioral, physiological and biochemical response to low (2°C) and high (45°C) temperatures was studied in Uromastyx aegyptius. Twelve animals were divided into two experimental groups. A third control group was kept at 22 °C. All animals in the cooling, warming, and control groups were allowed a period of 24 hours for adjustments at 22 °C. Blood samples were collected from each animal when body temperature reached the corresponding levels. The results showed a significant (P<0.05) decrease in blood glucose and cholesterol levels during cooling (2°C). This reduction in extracellular fluid substrates reflects an increase in cellular uptake of these substrates. Warming (45°C) resulted in a significant (P< 0.05) increase in total proteins, urea, and uric acid. These later changes could be attributed to an increase in the evaporative water loss, particularly due to the increased observed panting, and the associated reduction in plasma volume. There were no significant (P>0.05) changes in T3 and T4, during cooling nor during warming. The results of this study suggest augmentation of anaerobic metabolism of the U.aegyptius during cooling as evident by reduction in blood glucose levels. Furthermore, shift of glucose from the extracellular to the intracellular fluids demonstrates anticipation against potential freezing in order to protect the animal from intracellular freezing.

The behavioral, physiological and biochemical response to low (2°C) and high (45°C) temperatures was studied in Uromastyx aegyptius. Twelve animals were divided into two experimental groups. A third control group was kept at 22 °C. All animals in the cooling, warming, and control groups were allowe...