The Grass Shrimp, Palaemonetes, Pugio: Hypoxic Influences on Embryonic Development

摘要

Grass shrimp,Palaemonetes pugio, can survive in brackish waters and estuarine ecosystems despite the frequent oscillations and fluctuations in salinity, temperature and oxygen. AdultP. pugiohave the ability to osmoregulate (Romney and Reiber 2011), change cardiac parameters to tolerate temperatures (not yet published, Mika and Reiber) and oxyregulate (Guadagnoli and Reiber 2013). Manipulation of cardiac parameters allows for these methods of regulation. However, cardiac contraction and internal convection of oxygen do not occur until later stages of embryonic development. Studies focused on these morphological and physiological advantages may provide further understanding of the regulatory mechanisms within grass shrimp embryos, larvae and adults. To answer these questions, experiments are conducted under controlled laboratory conditions. The purpose of this study is to examine the effects of varying oxygen conditions onPalaemonetes pugio, a brackish water crustacean. Specifically, the study determines whether developmental and physiological changes contribute to increased survivorship ofP. pugioembryos. Changes in rate of embryonic oxygen consumption under normoxic conditions during cardiac development will be compared with oxygen consumption rates under hypoxic conditions to quantify any changes in oxygen uptake. Furthermore, we will determine if exposure to variable oxygen conditions influences metabolic processes, whether oxyconformation shifts to oxyregulation and finally, quantify the amount of lactate production perP. pugioclutch.