The total (THC) and differential (DHC) haemolymph counts as well as the morphological and intracellular disorders in haemocytes of nymphs and adults of the desert locust Schistocerca gregaria were investigated after treatment of penultimate instar nymphs with F.bruguieri extracts. With no exception, THC in haemolymph of the early-aged nymphs increased, irrespective of the extract or concentration level. Reversely, THC in the haemolymph of nymphs at mid- and late-ages was remarkably dropped, regardless to the extract or concentration level. Concerning the adults both the methanolic and petroleum ether extracts exhibited an increasing effect on THC while the n-butanolic extract exerted a serious prohibitory effect.
Three types only of haemocytes were identified in last instar nymphs and newly emerged adults of the present insect species: plasmatocytes, granulocytes and coagulocytes. As a response to the methanolic extract, plasmatocyte counts significantly decreased in the early- and mid-aged nymphs, but remarkably increased in the late-aged ones. Also, plasmatocyte counts in haemolymph of adults were pronouncedly regressed. After treatment with petroleum ether extract, plasmatocyte counts were unexceptionally reduced in nymphs and adults. In addition, a drastic prohibiting action of n-butanolic extract was exerted on plasmatocyte counts in all nymphs, except late-aged ones, and in adults. After treatment with methanolic extract, increasing granulocyte counts were observed in haemolymph of the early- and late-aged nymphs , while mid-aged nymphs had slightly decreased counts or no change. After treatment with petroleum ether extract, considerable increments in the granulocyte counts were observed, irrespective of the stage, age, or concentration level. Reversely, granulocyte counts decreased as a response to the effect of n-butanolic extract in nymphs and adults. Varied effects of the F. bruguieri extracts were distinctively recorded in coagulocyte counts, depending on the nymphal age. In addition, remarkably increased counts were determined in haemolymph of adults.
Haemocytes of nymphs and adults of S.gregaria were morphologically affected by the methanolic and n-butanolic F. bruguieri extracts because some small darkened granulocytes and lysed granulocytes appeared. Also, lysed coagulocytes, with ruptured cell membrane and extruding cytoplasmic contents, were observed.In addition, cytoplasm of some haemocytes appeared with various vacuoles as well as a number of vacuoles appeared in the nuclei of some granulocytes .