LAUFER, Hans*; DEMIR, Neslihan; BIGGERS, William; University of Connecticut, Storrs; University of Connecticut, Storrs; Wilkes University, Wilkes-Barre: Lobster�s Response to Stressors of Shell Disease
Lobster�s Response to Stressors of Shell Disease Hans Laufer1,2*, Neslihan Demir1 and William J. Biggers1, 3 1Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT , 06269-3125 2The Marine Biological Laboratory, Woods Hole, MA , 02543 3 Present address: Department of Biology, Wilkes University, Wilkes-Barre, PA, 18766 E-mail: laufer@uconn.edu Shell disease is a problem affecting up to 67% of the lobsters in Eastern Long Island Sound, that causes disfiguration of the shell, decreasing the lobsters� value, and ultimately results in their mortality. Less well understood is the effect of this disease on the endocrine system that regulates molting, cuticle repair, regeneration, growth, and reproduction, and the involvement of the endocrine system in the repair of shell disease. Levels of the molting hormone, ecdysone, were quantitated in hemolymph of unaffected normal lobsters and those exhibiting varying degrees of shell disease using a radioimmunoassay (RIA). Our results indicate that levels of ecdysone were increased in the hemolymph of shell diseased lobsters with an average 89�32 ng/ml (n=76) over healthy ones, which had 57�16 ng/ml (n=210). This result is highly significant by 2 way analysis of variance, with P=0.002. Ecdysone levels were abnormally high in shell diseased ovigerous lobsters, with an average of 165�53ng/ml (n=5), while unaffected egg bearing lobsters had low levels of this hormone with an average of 13�4 ng/ml (n=7). These results were found to be highly significant (P<0.005) when analyzed for significance by the students t-test. Our results indicate that shell disease induces lobsters to alter their systemic levels of ecdysone, possibly serving as a defensive measure by which the animals are able to ward off the effects of shell disease through induced molting. (Supported by the Sea Grant College Program and CT. DEP)
