Mass Dynamics during Embryonic Development and Parental Investment in Cottonmouth Neonates

Follicle and embryo development in the cottonmouth Agkistrodon piscivorus were studied in adult females collected from a cypress swamp along the Savannah River in Aiken County, South Carolina. Non-polar lipids were extracted from follicles, eggs, embryos, and neonates. Egg dry mass averaged 4.70 g and was composed of 23.6% non-polar lipids. Neonate dry mass averaged 3.35 g and was composed of 18.8% non-polar lipids. The rate of decrease in the dry mass of egg components remained fairly constant in the early stages of development and then accelerated during the last third of embryo development, a period that corresponds with the most rapid phase of embryo growth. An average of 57% of the original egg non-polar lipids remained in neonates as parental investment in care (PIC). At a temperature of 30 C, stored lipids would fuel a neonate's standard metabolic rate for approximately 22 days.