Oxygen consumption during gravidity compared to digestion and exhaustive activity in the viviparous Checkered Garter Snake

Abstract

The goal of this research was to measure oxygen consumption (i.e. VO2) associated with exhaustive activity, digestion, and gravidity in the viviparous Checkered Garter Snake. To determine gravidity, female snakes were imaged with a portable ultrasound. Gas analysis was performed using flow through respirometry with carbon dioxide and oxygen sensors. Current results indicate that gravid female Checkered Garter Snakes increase resting VO2 up to 1.6 fold the values the non‐gravid state. Furthermore, gravid females demonstrate a higher VO2 during digestion (scope = 1.5), but demonstrate a lower peak VO2 during fasting exhaustive activity (scope= .83). Both gravid and non‐gravid females exhibit a higher VO2 during post‐prandial exhaustive activity compared peak VO2 during either exhaustive activity or digestion. Therefore, this species demonstrates an additional capacity for oxygen consumption that is revealed only when simultaneously digesting a large meal and maximally active. Funding was provided by NSF grant IOS 0922756 to JWH.