Seasonal Variation of Serum Cholesterol and Thyroid Hormone Levels Associated with Hibernation in Indian Common Toad, Duttaphrynus melanostictus (Schneider, 1799)

Suman Pratihar, Jayanta Kumar Kundu


In this study it was tried to investigate that the seasonal variation of thyroid hormone was associated with hypometabolism during the phase of hibernation in Indian common toad (Duttaphrynus melanostictus). The decline in thyroid hormone concentration had its behavioral and physiological response that leads to increase and sustain cholesterol level in serum, which seems to be the most important metabolite during the hibernating phase. So it may be inferred that reduced thyroid hormone is associated with metabolism depression and also help to shift the metabolism towards lipid.


Duttaphrynus melanostictus; hypometabolism; serum cholesterol; thyroid hormone

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