Effects of different levels of magnetic fields on development of egg and yolk sac larvae of gilthead sea bream (Sparus aurata, L.)

In this study the influence of three different magnetic fields investigated on embryonic development, growth parameters, digestive physiology (absorption of endogenous food reserves) and oxidative status (superoxide dismutase and catalase) and digestive enzyme (total protease) activities of egg and yolk sac larvae in gilthead sea bream, Sparus aurata. In this sense S. aurata egg were obtained from breeders in natural spawning season and transferred to experimental tanks in four groups. Similarly, newly hatched yolk sac larvae of S. aurata were classified into four groups. Magnetic fields were established with neodymium magnets in three different levels, 1, 3 and 5 mT. Control groups were not exposed magnetic field. Embriyonic development of egg was accelerated in 3 and 5 mT groups, they hatched out relatively earlier than control and 1mT groups. In terms of hatching rate, M3 and M% was found significantly different than M1 and control group. In yolk-sac larvae, although magnetic fields did not achieve significant differences on growth parameters, it caused significant differences on activities of antioxidant and digestive enzymes. In terms of larval survival, M5 presented significant differences comaopred to ather experimental groups.