Meeting Abstract

P3.145  Tuesday, Jan. 6  Mummichog (Fundulus heteroclitus) from Cape Cod have a lower frequency of spontaneous ovarian contractions than has been reported from a Delaware population. JENSEN, BH*; CASEY, A; The College of Saint Rose; The College of Saint Rose jensenb@strose.edu

It is well established that the ovaries of teleost fish spontaneously contract. However, the purpose of these contractions is not well understood largely because there is so much variability in the frequency, amplitude, and timing of the spontaneous ovarian contractions between different species of fish. Our lab has been working with Danio rerio (zebrafish) and Fundulus heteroclitus (mummichog) to try and elucidate the purpose of these contractions. We have previously reported the presence of spontaneous contractions in the zebrafish and lack of regular spontaneous contraction in a northern population of mummichog. Both of these findings led us to the conclusion that there is indeed some reproductive role for spontaneous ovarian contractions in fish. We are currently presenting data that indicate that the Cape Cod population of mummichog that we are working with has a much lower frequency of spontaneously occurring ovarian contractions in sexually mature fish than has been reported in their southern counterparts (southern Delaware). Both the northern and southern populations are strongly responsive to Acetylcholine, indicating they are both capable of contacting. The fact that the northern population generally lack spontaneous contractions indicates that function of these contractions may have little importance in the mummichog further confusing our understanding of the role of spontaneous ovarian contractions in fish. Additionally, the current study points to physiological difference in the reproduction of the northern and southern populations of mummichog in the past behavioral differences were primarily noted.