Amir Vazirizadeh

The sub-acute toxicity of the crude tentacle-only extract from the alien Cassiopea andromeda (forsskal , 1775) jellyfish was studied in rat within 21 days after exposure. For sub-acute toxicity, changes in weights and pathological parameters were studied. The intraperi toneal LD50 value of venom was estimated 104.0 µg/kg BW in male mice. For sub-acute toxicity, 3 doses of crude venom (0.0125, 0.025 and 0.05 µg/ml/day) were administered intraperitoneally to female rats, once daily for 21 days. Increase in size and weights were observed in the spleens in all groups. The Scab-like spots were seen on skin of all the rats. Histopathological examinations of t he rat kidney, heart, liver and spleen tissues indicated that ther e were different demonstrable abnormalities and alt erations in the microscopic examinations in comparison to their control groups, especially at a higher dose of 0.05 µg /ml/day.