Meeting Abstract

P2.79  Jan. 5  Morphology of the esophagus, digestive gland, and intestine in wild-caught and cultured giant keyhole limpets, Megathura crenulata MARTIN, G.G.*; BESSETTE, T.; MARTIN, A.M.; OAKES, C.; Occidental College, Los Angeles gmartin@oxy.edu

The giant keyhole limpet, Megathura crenulata, is found in intertidal and subtidal areas from Point Conception, CA to Baja California, where it feeds on a variety of leafy algae. Its respiratory pigment, hemocyanin, forms unusually large aggregates which are proving effective in cancer therapies. The purpose of this study is to examine the morphology of several regions of the gut in limpets caught in the wild and compare them with those maintained in culture facilities. Limpets from the wild have a higher mortality rate than those raised in culture which could be due to differences in their age, environmental fluxes, or possibly parasite load. Many mollusks harbor intracellular parasites in gut tissues, which are often regarded as benign. In the abalone, Rickettsiales-like bacteria have been found in cells of the esophagus, digestive gland and intestine. Under stressful conditions these bacteria have been implicated in withering foot syndrome. Our work will describe the cell types in the esophagus, digestive gland, and intestine of cultured and wild-caught limpets using light and electron microscopy. Particular attention is focused on the presence of cellular inclusions which may be of microbial origin.