Feeding, brain implantation and 20-hydroxyecdysone treatment reverses the effect of starvation and ventral nerve cord severance on haemocyte counts in larvae of the plain tiger butterfly Danaus chrysippus (Lepidoptera: Nymphalidae)

Total and differential haemocyte counts following starvation and feeding resumption, ventral nerve cord transection, and brain implantation followed by methoprene application and 20-hydroxyecdysone injection were studied in Danaus chrysippus (Linnaeus) larvae. The results revealed that initial starvation and transection of the ventral nerve cord before the fifth abdominal ganglion in fifth instars of D. chrysippus led to a reduced total haemocyte count, on the one hand, and to a higher variation in percentage of different haemocyte types, on the other. While feeding resumption, brain implantation and 20-hydroxyecdysone treatments reversed the effect of starvation and nerve cord transection, methoprene application produced a decline in total number of haemolymph cells.