Thermotaxis in third and fourth-stageDirofilaria immitislarvae

Abstract

Third-stage and fourth-stageDirofilaria immitislarvae exhibited positive thermotaxis when placed in a thermal gradient. Negative thermotaxis was not observed. Positive thermotaxis may be important for the successful transmission and for directing third and fourth-stage larval migration toward predilection sites in the Host.

Sperm thermotaxis

“…Cells and lower organisms commonly employ thermotaxis for migrating to preferable temperatures. Thermotaxis was first discovered in the unicellular slime mold Dictyostelium discoideum (Bonner et al, 1950;Raper, 1940) and then, among others, in Caenorhabditis elegans (Hedgecock and Russell, 1975), bacteria (Maeda et al, 1976), parasites like Dirofilaria immitis larvae (Mok et al, 1986), Drosophila (Sayeed and Benzer, 1996), human polymorphonuclear leukocytes (Kessler et al, 1979;Mizuno et al, 1992), human trophoblastic cells (Higazi et al, 1996), and mammalian spermatozoa (Bahat et al, 2003). In some systems [e.g., bacteria (Maeda et al, 1976), D .…”