Abdu, U., Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Barki, A., Department of Aquaculture, Institute of Animal Science, Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Karplus, I., Department of Aquaculture, Institute of Animal Science, Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Barel, S., National Residue Control Laboratory, Kimron Veterinary Institute, P.O. Box 12, Bet-Dagan 50250, Israel
Takac, P., Institute of Zoology, Slovak Academy of Sciences, Bratislava 84206, Slovakia
Yehezkel, G., Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Laufer, H., Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, United States
Sagi, A., Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Barki, A., Department of Aquaculture, Institute of Animal Science, Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Karplus, I., Department of Aquaculture, Institute of Animal Science, Volcani Center, P.O. Box 6, Bet-Dagan 50250, Israel
Barel, S., National Residue Control Laboratory, Kimron Veterinary Institute, P.O. Box 12, Bet-Dagan 50250, Israel
Takac, P., Institute of Zoology, Slovak Academy of Sciences, Bratislava 84206, Slovakia
Yehezkel, G., Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Laufer, H., Department of Molecular and Cell Biology, University of Connecticut, Storrs, CT 06269, United States
Sagi, A., Department of Life Sciences, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 84105, Israel
Methyl farnesoate (MF), the predominant juvenile hormone-like compound of crustaceans, was found in the hemolymph of female Cherax quadricarinatus crayfish. Administration of MF to C. quadricarinatus females during their winter reproductive arrest period had no effect on reproduction; however, it did have a tendency to accelerate molting. However, since MF caused increased mortality (∼47% survival in the high MF treatment), we were not able to draw definitive conclusions regarding its physiological affect. In contrast, administration of pyriproxyfen, a juvenile hormone analog, did not cause significant mortality (95% survival in the high pyriproxyfen treatment), although it accumulated in high quantities in the hepatopancreas and, to a lesser extent, muscle tissue, ovaries and gills. The highest dose of pyriproxyfen used in this study, 20 μg/gram animal body weight/week, caused a delay in spawning, which became statistically significant from the seventeenth week. This dose of pyriproxyfen caused a tendency of acceleration of molting without any effect on molt increment. The results of this study show that pyriproxyfen does not seem to be toxic to the crayfish, even in relatively high doses, and might affect the energetic balance between molt and reproduction. © 2001 Elsevier Science B.V. All rights reserved.
